Terminology and Acronyms Flashcards

Question 1

Q

Abrasion Resistance

Answer

A

The ability of material to resist being worn away and to maintain its original appearance and structure when subjected to rubbing, scraping, or wear.

Question 2

Q

Abrasive

Answer

A

A solid substance that, owing to its hardness, toughness, size shape consistency, or other properties, is suitable for grinding, cutting, roughening, polishing, or cleaning a surface by friction or high-velocity impact.

Question 3

Q

Abrasive Blast Cleaning

Answer

A

Cleaning and roughening of a surface produced by the high-velocity impact of an abrasive that is propelled by the discharge of pressurized fluid from a blast nozzle or by a mechanical device such as a centrifugal blasting well. [also referred to as ABRASIVE BLASTING]

Question 4

Q

Abrasive Blasting

Answer

A

See Abrasive Blast Cleaning

Question 5

Q

Accelerator

Answer

A

A chemical substance that increases the rate at which a chemical reaction (e.g., curing) would otherwise occur.

Question 6

Q

AC Impedance

Answer

A

See Electrochemical Impedance

Question 7

Q

Acrylic

Answer

A

Type os resin polymerized from acrylic acid, methacrylic acid, esters of these acids, or acrylonitrile.

Question 8

Q

Activator

Answer

A

A chemical substance that initiates a chemical reaction (e.g., curing) Heat and radiation may also serve as activators for some chemical reactions.

Question 9

Q

Active

Answer

A

(1) A State of a metal surface that is corroding without significant influence of reaction product. (2) The negative direction of electrode potential.

Question 10

Q

Active-passive cell

Answer

A

An electrochemical cell in which the anode is a metal in the active state and the cathode is the same metal in the passive state.

Question 11

Q

Adduct Curing Agent

Answer

A

A material that is formed by prereacting the curing agent with a portion of the resin component of the coating.

Question 12

Q

Adhesion

Answer

A

The state in which two surfaces are held together by chemical interfacial forces, mechanical interlocking forces, or both.

Question 13

Q

Aeration Cell

Answer

A

See Differential Aeration Cell

Question 14

Q

Aging

Answer

A

(1) The process of exposing materials to an environment of an interval of time. (2) Change in metallurgical properties that generally occurs slowly at room temperature (natural aging) and more rapidly at higher temperature (artificial aging).

Question 15

Q

Air Drying

Answer

A

Process by which an applied wet coat converts to a dry coating film by evaporation of solvent or reaction with oxygen as a result of simple exposure to air without intentional additional of heat or a curing agent.

Question 16

Q

Airless Spraying

Answer

A

Process of spraying coating liquids using hydraulic pressure, not air pressure, to atomize.

Question 17

Q

Alkyd

Answer

A

Type of resin formed bu the reaction of polyhydric alcohols and polybasic acids, part of which is derived from saturated or unsaturated oils or fats.

Question 18

Q

Alligatoring

Answer

A

Pronounced wide cracking over the surface of a coating, which has the appearance of alligator hide.

Question 19

Q

Alloy steel

Answer

A

an iron-based alloy containing carbon (usually less than 2.5 mass percent), manganese (usually greater than 0.25 mass percent), and specified minimum quantities of one or more alloying elements other than manganese, silicon, and copper, but does not contain 10.5 mass percent or greater chromium.

Question 20

Q

Alternate Immersion

Answer

A

Exposure to environmental cycles, each involving immersion in a fluid for a period of time followed bu removal from that fluid or another period of time.

Question 21

Q

Amphoteric Metal

Answer

A

A metal that is susceptible to corrosion in both acidic and alkaline environments.

Question 22

Q

Anaerobic

Answer

A

Absence of air or free (molecular) oxygen.

Question 23

Q

Anchor Pattern

Answer

A

See Surface Profile

Question 24

Q

Anion

Answer

A

A negatively charged Ion.

Question 25

Q

Anneal

Answer

A

Heat to and hold at a temperature appropriate for the specific material and then cool at a suitable rate, for such purposes as reducing harness, improving machinability, or obtaining desired properties.

Question 26

Q

Anode

Answer

A

The electrode of an electrochemical cell at which oxidation occurs. (electrons flow away from the anode in external circuit. It is usually the electrode where corrosion occurs and metal ions enter solution.)

Question 27

Q

Anode Cap

Answer

A

An electrical insulating material placed over the end of the anode at the lead wire connection.

Question 28

Q

Anode Corrosion Efficiency

Answer

A

The ration of the actual corrosion (mass loss) of an anode to the theoretical corrosion (mass loss) calculated from the quantity of electricity that has passed between the anode and cathode using Faraday’s law.

Question 29

Q

Anodic Inhibitor

Answer

A

A corrosion inhibitor whose primary action is to reduce the rate of the anodic reaction, producing a positive shift in corrosion potential.

Question 30

Q

Anodic Polarization

Answer

A

The change of electrode potential caused by an anodic current flowing across the electrode/electrolyte interface. (2) A forced noble (positive) shift in electrode potential. [See POLARIZATION.]

Question 31

Q

Anodic Protection

Answer

A

A technique to reduce the corrosion rate of a metal surface by polarizing that surface to a more oxidizing potential.

Question 32

Q

Anodizing

Answer

A

An electrochemical oxidation process that converts the surface of a metal (such as aluminum or titanium) to an oxide coating.

Question 33

Q

Anolyte

Answer

A

The electrolyte adjacent to the anode of electrochemical cell

Question 34

Q

Antifouling

Answer

A

Preventing fouling

Question 35

Q

Atmospheric Zone

Answer

A

The portion of a marine structure that extends upward from the splash zone and is exposed to sun, wind, water spray, and rain.

Question 36

Q

Attenuation

Answer

A

Electrical losses in a conductor caused by current flow in the conductor.

Question 37

Q

Auger Electron Spectroscopy

Answer

A

Analytical technique in which the sample surface is irradiated with low-energy electrons and the energy spectrum of electrons emitted from the surface is measured.

Question 38

Q

Austenite

Answer

A

The face-centered cubic crystalline phase of iron or iron-based alloys.

Question 39

Q

Austenitic/Ferritic Stainless Steel

Answer

A

See Duplex Stainless Steel

Question 40

Q

Austenitizing

Answer

A

Forming Asutenite by heating iron or iron-based alloys to temperature in the transformation range (partial austenitizing) or above the transformation range (complete austenitizing).

Question 41

Q

Auxiliary Electrode

Answer

A

See Counter Electrode

Question 42

Q

Backfill

Answer

A

Material placed in a hole to fill the space around the anodes, vent pipe, and buried components of a cathodic protection system.

Question 43

Q

Barcol Hardness

Answer

A

A hardness value obtained by measuring the resistance of rubbers, plastics, or coatings to indentation by a steel impresser under spring load in accordance with Test Method D2583.

Question 44

Q

Barrier Coating

Answer

A

(1) A coating that has a high resistance to permeation of liquids and/or gases. (2) a coating that is applied over a previously coated during subsequent handling.

Question 45

Q

Beach Marks

Answer

A

The characteristic markings on the fracture surfaces produced by fatigue crack propagation. [also known as arrest marks, clamshell marks, and conchoidal marks]

Question 46

Q

Beta Curve

Answer

A

A plot of dynamic (fluctuating) interference current or related proportional voltage (ordinate) versus the corresponding structure-to-electrolyte potentials at a selected location on the affected structure (abscissa)

Question 47

Q

Binder

Answer

A

The nonvolatile portion of the vehicle of a formulated coating material.

Question 48

Q

Bituminous Coating

Answer

A

An asphalt or coal-tar compound used to provide a protective coating for a surface.

Question 49

Q

Blast Angle

Answer

A

(1) The angle of the blast nozzle with reference to the surface during abrasive blast cleaning. (2) The angle of the abrasive particles propelled from a centrifugal blasting wheel with reference to the surface being abrasive blast cleaned.

Question 50

Q

Blister

Answer

A

A dome-shaped projection on the surface of a coating resulting from the local loss of adhesion and lifting of the film from an underlying coat of from the base substrate.

Question 51

Q

Blooming

Answer

A

See Blushing

Question 52

Q

Blowdown

Answer

A

(1) The injection of air or water under high pressure through a tube to the anode area for the purpose of purging the annular space and possibly correcting high resistance caused by gas blockage. [cathodic protection use] (2) The process of discharging a significant portion of the aqueous solution in order to remove accumulated salts deposits, and other impurities. [boiler or cooling water tower use]

Question 53

Q

Blushing

Answer

A

Whitening and loss of gloss of a coating, usually organic, caused by moisture. [also known as blooming]

Question 54

Q

Bracelet Anode

Answer

A

A galvanic anode with geometry suitable for direct attachment around the circumference of a pipeline. This may be half-shell bracelet consisting of two semicircular sections or a segmented bracelet consisting of a large number of individual sections.

Question 55

Q

Braze

Answer

A

(1) A bond produced as the result of heating an assembly to the brazing temperature greater than 450 °C [840 °F] and less than the solidus temperature of the base metal using a brazing filler metal distributed and retained between the closely fitted facing surfaces of the joint by capillary action. (2) the Act of creating a braze.

Question 56

Q

Breakdown Potential

Answer

A

The least noble potential at which pitting or crevice corrosion, or both, will initiate and propagate in a specific environment.

Question 57

Q

Brinell Hardness

Answer

A

Hardness value, measured in accordance with ISO 6506-1 or Test Method E10, normally using a 10 mm diameter tungsten carbide ball and a force of 29.42 kN.

Question 58

Q

Brittle Fracture

Answer

A

Fracture that occurs with little or no plastic deformation of the material. [contrast with DUCTILE FRACTURE]

Question 59

Q

Brush-off Blast Cleaned Surface

Answer

A

An abrasive blast cleaned steel surface that is free of all visible contaminants and foreign matter but may have some tightly adherent mill scale, rust, or coating. [See NACE No. 4/SSPC-SP 7 for Detailed specification.]

Question 60

Q

Burnish

Answer

A

Process of smoothing surfaces using frictional content between the material and some other hard pieces of hard material (e.g., hardened steel balls).

Question 61

Q

Calcareous Deposit

Answer

A

See Calcareous Coating

Question 62

Q

Carbon Steel

Answer

A

Allow of carbon and iron containing up to 2 mass percent carbon and up to 1.65 mass percent manganese and residual quantities of other elements, except those intentionally added in specific quantities for deoxidation (usually silicon and/or aluminum)

Question 63

Q

Carburizing

Answer

A

The absorption and diffusion of carbon in iron or an iron-based alloy in contact with a suitable carbonaceous environment at elevated temperature.

Question 64

Q

Case Hardening

Answer

A

Hardening a ferrous alloy so that the outer portion, or case, is made substantially harder than the inner portion, or core. Typical processes are carburizing, cyaniding, carbonitriding, nitriding, induction hardening, and flame hardening.

Answer 65

A

Water-thinned paint with vehicle derived from milk.

Answer 66

A

A chemical substance, usually present in small amounts relative to reactants, that increases the rate at which a chemical reaction (e.g., curing) would otherwise occur, but is not consumed in the reaction.

Answer 67

A

The electrode of an electrochemical cell at which reduction is the principal reaction. (Electrons flow toward the cathode in the external circuit.)

Answer 68

A

The conjoint action of cavitation and corrosion.

Answer 69

A

The degradation of a solid body resulting from its exposure to cavitation. (This may include loss of material, surface deformation, or changes in properties or appearance.)

Answer 70

A

The conjoint action of cavitation and erosion.

Answer 71

A

See Electrochemical Cell

Answer 72

A

The introduction of one or more elements into the surface layer of a metal or alloy by diffusion at high temperature. (Examples of cementation include carburizing [introduction of carbon], nitriding [introduction of nitrogen], and chroming [introduction of chromium].)

Answer 73

A

Iron carbide (Fe3C) when referred to as a microstructural constituent of steel.

Answer 74

A

The development of loose, removable powder (pigment) at the surface of organic coating, usually caused by weathering.

Answer 75

A

The development of slight breaks in a coating that do not penetrate to the underlying surface.

Answer 76

A

An adherent, reaction-product layer on a metal surface formed in situ by reaction with a suitable chemical, used for protective, decorative, or functional purposes. (It is often used to provide greater corrosion resistance or prepare the surface prior to the application of an organic coating.)

Answer 77

A

A V-shaped on a fatigue or brittle-fracture surface. The pattern can also be one of straight radial lines on cylindrical specimens.

Answer 78

A

(1) Removing coating and surface contaminants from a substrate by mechanical means. (2) A type of coating failure caused by mechanical damage, loss of adhesion, or both.

Answer 79

A

Cracking of a metal under the combined action of tensile stress and corrosion in the presence of en electrolyte containing dissolved chlorides.

Answer 80

A

Fracture that occurs along planes determined by the crystal structure of the material. (It is typically associated with a brittle fracture.)

Answer 81

A

One layer of a coating system applied to a surface in a single continuous application to form a uniform film when dry.

Answer 82

A

(1) a liquid, liquefiable, or mastic composition that, after application to a surface, is converted into a solid protective, decorative, or functional adherent film. (2) (in a more general sense) A think layer of solid material on a surface that provides improved protective, decorative, or functional properties.

Answer 83

A

The complete number and types of coasts applied to a substrate in a predetermined order. (When used in a broader sense, surface preparation are included.)

Answer 84

A

Cracking of a weld during or after cooling to ambient temperature, sometimes after a considerable time delay. (It usually occurs at temperatures less than 205 °C [400 °F].)

Answer 85

A

A linear discontinuity with rounded edges at exposed surfaces that is caused by solidification of the meniscus of a partially cast metal or alloy (e.g., an anode used for cathodic protection) as a result of interrupted flow of the casting stream or the joining of two casting streams at too low a temperature.

Answer 86

A

Horizontal surface discontinuity caused by solidification of a portion meniscus during the progressive filling of a mold, which is later covered with more solidifying metal as the molten metal level rises. Cold shuts generally occur at corner remote from the point of pour.

Answer 87

A

Deforming metal plastically under conditions of temperature and strain rate that induce strain hardening, usually, but not necessarily, performed at room temperature [contract with hot working].

Answer 88

A

An abrasive blast cleaned steel surface that is free of all visible contaminants and foreign matter but may have some random staining on no more than 33 percent of the surface area. [See NACE No. 3/SSPC-SP 6 for detailed specification.]

Answer 89

A

The maximum compressive stress a material is capable of withstanding without sustaining permanent deformation.

Answer 90

A

An electrochemical cell, the electromotive force of which is caused by a difference in concentration of some component in the electrolyte. (This difference leads to the formation of discrete cathodic and anodic regions.)

Answer 91

A

That portion of polarization of an electrochemical cell produced by concentration changes resulting from current flowing through the electrolyte.

Answer 92

A

(1) A coating that conducts electricity. (2) an electrically conductive, mastic-like material used as an impressed current anode on reinforced concrete surfaces.

Answer 93

A

A highly conductive cement-based moisture containing coarse and fine coke and other materialized as an impressed current anode on reinforced concrete surfaces.

Answer 94

A

(1) a measure of the ability of a material to conduct an electric charge. (2) the current transferred across a material (e.g., coating) per unit area per unit potential gradient. (Conductivity is the reciprocal of resistivity.)

Answer 95

A

See Galvanic Corrosion

Answer 96

A

A connection, usually metallic, that provides electrical continuity between structures that can conduct electricity.

Answer 97

A

A single anode with no electrical discontinuities.

Answer 98

A

See Chemical Conversion Coating

Answer 99

A

(1) A test method in which a solution of copper sulfate, and possibly other ingredients, in water is swabbed onto the surface of certain metals to determine the presence of metals more active (anodic) than copper. (2) a spot test method in which a 5 to 1- perfect solution of copper sulfate in water is swabbed onto a steel surface to determine whether mill scale is present. (The appearance of copper indicates that mill scale is not present.)

Answer 100

A

The deterioration of a material, usually a metal, that results from a chemical or electrochemical reaction with its environment.

Answer 101

A

A Pigment that, when formulated into a liquid a coating material, has the property of reducing corrosion of the metal substrate to which the coating is applied.

Answer 102

A

The process wherein a metal fractures prematurely under conditions of simultaneous corrosion and repeated cyclic loading at lower stress levels or fewer cycles than would be required to cause fatigue of that metal in the absence of the corrosive environment.

Answer 103

A

The maximum repeated stress that can be endured by a metal without fracture under definite conditions of corrosion and cyclic loading for a specific number of stress cycles and a specified period of time.

Answer 104

A

A chemical substance or combination of substances that, when present in the proper concentration and forms in the environment, reduces the corrosion rate.

Answer 105

A

(represented by the symbol E-corr) The potential of a corroding surface in an electrolyte measured under open-circuit conditions relative to a reference electrode. [also known as ELECTROCHEMICAL CORROSION POTENTIAL, FREE CORROSION POTENTIAL, OPEN-CIRCUIT POTENTIAL]

Answer 106

A

The time rate of change of corrosion. (It is typically expressed as mass loss per unit area per unit time, penetration per unit time, etc.)

Answer 107

A

Ability of a material, usually a metal, to withstand corrosion in a given environment.

Answer 108

A

The tendency of an environment to cause corrosion.

Answer 109

A

The electrode in an electrochemical cell that I used to transfer current to or from a working electrode.

Answer 110

A

A conductor or system of conductors arranged beneath a power line, located on, above, or most frequently, below the surface of the earth and connected to the footings of the towers or poles supporting the power line.

Answer 111

A

See Galvanic Couple

Answer 112

A

A portion of a material or sample, usually flat, but occasionally curved or cylindrical, from which one or more specimens can be taken for testing.

Answer 113

A

(1) A partial split or break. (2) A split or break in a coating that penetrates to the substrate.

Answer 114

A

Fracture of a material along a path that produces a linear discontinuity (without complete separation).

Answer 115

A

(1) A metal surface anomaly consisting of a bowl-shaped cavity with the minimum dimension at the opening greater than the depth. [contrast with PIT] (2) a small, rounded dish or bowl-like depression in a wet-applied coating. [contract with FISH EYE]

Answer 116

A

A network of checks or cracks appearing on the surface of a coating.

Answer 117

A

Time-dependent strain occurring under stress.

Answer 118

A

That stress which, when applied to a material at a specific temperature, will cause a specified amount of elongation in a specified time.

Answer 119

A

Localized corrosion of a metal or alloy surface at, or immediately adjacent to, an area that is shielded from full exposure to the environment because of close proximity of the metal or alloy to the surface of another material or an adjacent surface of the same metal or alloy.

Answer 120

A

The maximum anodic current density observed int he active region for a metal or alloy electrode that exhibits active-passive behavior in an environment.

Answer 121

A

The relative humidity above which the atmospheric corrosion rate of a specific metal or alloy increases sharply.

Answer 122

A

(represented by the symbol Ep or App) The least noble potential at which pitting corrosion will initiate and propagate in a specific environment. [See breakdown potential.]

Answer 123

A

Chemical process of developing the intended properties of a coating or other material (e.g., resin) over a period of time.

Answer 124

A

A chemical substance used for curing a coating or other material (*e.g., resin) [also referred to as HARDENER]

Answer 125

A

The minimum period between application and the time at which the applied material attains its intended physical properties.

Answer 126

A

(1) a flow of electric charge. (2) the amount of electric charge flowing past a specified circuit point per unit time, measured in the direction of net transport of positive charges. (In a metallic conductor, this is the opposite direction of the electron flow.)

Answer 127

A

The electric current flowing to or from a unit area of an electrode surface.

Answer 128

A

The ration of the electrochemical equivalent current density for a specific reaction to the total applied current density.

Answer 129

A

A device used in electrical circuits that allows the flow of alternating current in both directions and stops or substantially reduces the flow of direct current.

Answer 130

A

The process of prior removal of the active corrosive constituents, usually oxygen, from a corrosive liquid by controlled corrosion of expendable metal or by other chemical means, thereby making the liquid less corrosive.

Answer 131

A

A corrosion process whereby one constituent of an alloy is preferentially removed, leaving an altered residual structure. [also known as PARTING, SELECTIVE DISSOLUTION, or SELECTIVE LEACHING].

Answer 132

A

The potential of an electrode surface at which the electrolyte, or a component thereof, decomposes by electrons.

Answer 133

A

See Decomposition Potential

Answer 134

A

One or more anodes installed vertically at a nominal depth of 15 m (50 ft) or more below the earth’s surface in a drilled hole for the purpose of supplying cathodic protection current.

Answer 135

A

(1) Separation of layers in a material. (2) A separation between one or more coats from another coat within a coating system. [contrast with DISBONDMENT] (3) A separation of the concrete (usually in layers) from the reinforcing steel at their interface, usually as a result of corrosion.

Answer 136

A

(1) Cracking in a metal occurring after plating or pickling, sometimes after a considerable time delay. (2) not a preferred term for COLD CRACKING.

Answer 137

A

(not a preferred term) The removal of factors resisting the current flow in an electrochemical cell. [See POLARIZATION.]

Answer 138

A

Localized corrosion under or around a deposit or collection of material on a metal surface. [also called POULTICE CORROSION] See also CREVICE CORROSION.]

Answer 139

A

Dealloying that results in the selective removal of zinc from copper-zinc alloys.

Answer 140

A

A coating that does not conduct electricity.

Answer 141

A

An electrically nonconductive material, such as a coating, sheet or pipe, that is placed between an node and an adjacent cathode, usually on the cathode, to improve current distribution in a cathodic protection system.

Answer 142

A

A concentration cell caused by differences in oxygen concentration along the surface of a metal in an electrolyte. [See CONCENTRATION CELL]

Answer 143

A

The current density that corresponds to the maximum transfer rate that a particular species can sustain because of the limitation of diffusion [often referred to as LIMITING CURRENT DENSITY].

Answer 144

A

The loss of adhesion between a coating and the substrate.

Answer 145

A

(1) an interruption in the normal physical structure or configuration of a coating such as cracks, laps, seams, inclusion, porosity, or holidays. (A discontinuity does not necessarily affect the usefulness of the coating.) (2) A condition in which the electrical path through a structure is interrupted by a drive that acts as a dielectric or insulating fitting.

Answer 146

A

Different metals that could form an anode cathode relationship in an electrolyte when connected by an electron-conducting (usually metallic =) path.

Answer 147

A

The interface between an electrode or a suspended particle and an electrolyte created by charge-charge integration leading to an alignment of oppositely charged ions at the surface of the electrode or particle. The simplest model is represented bu a parallel plate condenser.

Answer 148

A

An additional plate or thickness of metal used to provide extra strength or thickness to a structure locally (e.g., at the point of anode attachment to an offshore structure).

Answer 149

A

Conduction of electric current from am underground or submerged metallic structure by means of a metallic conductor.

Answer 150

A

Difference in potential between the anode and the steel structure.

Answer 151

A

The thickness of a dried mild, coating, or membrane.

Answer 152

A

A rough, powdery non coherent film produced when atomized coating particles partially dry before reaching the surface.

Answer 153

A

Stage of drying or curing of an applied coating at which time the coated object can be carefully handled without damage.

Answer 154

A

Stage of drying or curing of an applied coating at which time a subsequent coat can be applied satisfactorily.

Answer 155

A

Stage of drying or curing of an applied coating at which time it no longer adheres to a finger that is lightly touched or rubbed across the surface and does not show a fingerprint at the point of contact.

Answer 156

A

The process in which a liquid film is converted to a solid film bu evaporation of volatile components.

Answer 157

A

An oil capable of conversion from a liquid to a solid by slow reaction with oxygen in the air.

Answer 158

A

Minimum time required for an applied coating to reach the desires stage of drying or curing.

Answer 159

A

Fracture that occurs with appreciable plastic deformation of the material to withstand plastic deformation prior to fracture. (It is usually measured by the permanent elongation or reduction in the cross-sectional are of a fractured tensile test specimen.)

Answer 160

A

The ability of material to withstand plastic deformation prior to fracture. (It is usually measured by the permanent elongation or reduction in the cross sectional area of a fractured tensile test specimen.)

Answer 161

A

Stainless Steel whose microstructure at room temperature consists primarily of a mixture of austenite and ferrite. [also called AUSTENITIC/FERRITIC STAINLESS STEEL].

Answer 162

A

Changes of dimensions of a material upon the application of a stress within the elastic range. Following the release of an elastic stress, the material returns to its original dimensions without any permanent deformation.

Answer 163

A

The property of a material that allows it to recover its original dimensions following deformation by a stress below its elastic limit.

Answer 164

A

The maximum stress to which a material may be subjected without retention of any permanent deformation after the stress is removed.

Answer 165

A

Any electrical disturbance on a metallic structure in contract with an electrolyte caused by stray currents(s)

Answer 166

A

The condition of being electrically separated from other metallic structures or the environment.

Answer 167

A

The reciprocal of the electrochemical impedance, 🔺I/🔺E.

Answer 168

A

(1) An electrochemical reaction involving two half reactions, one of which involves oxidation of the reactant (product) and the other of which involves reduction of the product (reactant). (The equilibrium potential of the electrochemical cell can be calculated from the change in free energy for the overall electrochemical reaction. The equilibrium potential of the electrochemical cell can be measured bu separating the oxidation and reduction half reactions into individual compartments and measuring the voltage that develops between them under conditions that virtually no charge passes between them.) [thermodynamic use] (2) An electrochemical system consisting of anode and cathode in metallic contact immersed in an electrolyte. (The anode and cathode may be different metals or dissimilar areas on the same metal surface.) [common use]

Answer 169

A

See Corrosion Potential

Answer 170

A

The mass of element or group of elements oxidized or reduced at 100 percent efficiency by the passage of a unit quantity of charge such as a Faraday (96,485 coulombs), ampere-hour, or coulomb.

Answer 171

A

The frequency dependent, complex valued proportionality factor, 🔺I/🔺E, between the applied potential (or current) and the response current (or potential) in an electrochemical cell. This factor becomes the impedance when the perturbation and response are related linearly (the factor value is independent of the perturbation magnitude) and the response is caused only by the perturbation. The value may be related to the corrosion rate when the measurement is made at the corrosion potential.

Answer 172

A

Flactuations of potential or current, or both, originating fro uncontrolled variations in a corrosion process.

Answer 173

A

The partial derivate of the total electrochemical free energy of the stem with respect to the number of moles of the constituent in a solution when all other factors are constant. (Analogous to the chemical potential of the constituent except that it includes the electrical as well as the chemical contributions to the free energy.)

Answer 174

A

A material that conducts electrons, us used to establish contact with an electrolyte, and through which current is transferred to or from an electrolyte.

Answer 175

A

The potential of an electrode is an electrolyte as measured against a reference electrode.

Answer 176

A

A potential difference in a solution caused by residual, unbalanced charge distribution in the adjoining solution, producing a double layer. (The electrokinetic potential is different from the electrode potential in that it occurs exclusively in the solution phase. The potential represents the reversible work necessary to bring a unit charge from infinity in the solution up to the interface in question but not through the interface.) [also known as ZETA POTENTIAL]

Answer 177

A

Production of chemical changes of the electrolyte by the current flowing through an electrochemical cell.

Answer 178

A

A process for removing soil, scale, or corrosion products from a metal surface by subjecting the metal as electrode to an electric current in an electrolytic bath.

Answer 179

A

A list of elements arranged according to their standard electrode potentials, the sign being positive for elements whose potentials are more noble than hydrogen such as gold and negative for those more active than hydrogen such as zinc. [not to be confused with GALVANIC SERIES]

Answer 180

A

The migration of water through a semipermeable membrane as a result of a potential difference caused by the flow of electric charge through the membrane.

Answer 181

A

An optical technique wherein place-polarized light is focused on a surface and the reflected beam is analyzed to determine the phase shift of the components of the light to provide information on the properties of films that may be present on the surface.

Answer 182

A

Reduction of ductility, or toughness, or both, of a material (usually a metal or alloy.)

Answer 183

A

See Electromotive Force Series

Answer 184

A

(1) A paint that dries to a hard, glossy, surface (2) A coating that is characterized by an ability to form a smooth, durable film.

Answer 185

A

The more rapid loss of anode material at the end of an anode, compared with other surfaces of the anode, resulting from higher current density.

Answer 186

A

The maximum stress that a material can withstand for an infinitely large number of fatigue cycles.

Answer 187

A

The surroundings or conditions (physical, chemical, mechanical) in which material exists.

Answer 188

A

Cracking of a material wherein an interaction with its environment is a causative factor in conjunction with tensile stress, often resulting in brittle fracture of an otherwise ductile material. [also known as ENVIRONMENTALLY ASSISTED CRACKING]

Answer 189

A

Environmental cracking is a general term that includes the terms listen below. The definitions of these terms are listed elsewhere in this document: CAUSTIC CRACKING, CHLORIDE STRESS CORROSION CRACKING, CORROSION FATIGUE, HYDROGEN EMBRITTLEMENT, HYDROGEN-INDUCED CRACKING (STEPWISE CRACKING), HYDROGEN STRESS CRACKING, LIQUID METAL CRACKING, STRESS CORROSION CRACKING, SULFIDE STRESS CRACKING.

Answer 190

A

The following terms have been used in the past in connection with environmental cracking but are now obsolete and should not be used: CAUSTIC EMBRITTLEMENT, delayed cracking, liquid metal embrittlement, SEASON CRACKING, static fatigue, sulfide corrosion cracking, sulfide stress corrosion cracking.

Answer 191

A

See Environmental Cracking

Answer 192

A

Type of resin formed by the reaction of aliphatic or aromatic polls (such as bisphenol) with epichlorohydrin and characterized by presence of reactive oxidant end groups.

Answer 193

A

The potential of an electrode in an electrolyte at which the forward rate of a given reaction is exactly equal to the reverse rate. (The equilibrium potential can only be defined with respect to a specific electrochemical reaction.) [also known as REVERSIBLE POTENTIAL]

Answer 194

A

The progressive loss of material from a solid surface resulting from mechanical interaction between that surface and a fluid, a multicomponent fluid, or solid particles carried with the fluid.

Answer 195

A

A conjoint action involving erosion and corrosion in the presence of a moving corrosive fluid or a material moving through the fluid, leading to accelerated loss of material.

Answer 196

A

The rate of charge transfer per unit area when an electrode reaches dynamic equilibrium (at its reversible potential) in a solution; that is, the rate of anodic charge transfer (oxidation) is exactly equal to the rate of cathodic charge transfer (reduction).

Answer 197

A

Subsurface corrosion that proceeds laterally from the sites of initiation along planes parallel to the surface forming corrosion products that force metal away from the body of the material, giving rise to a layered appearance resembling the pages of a book.

Answer 198

A

The wires, connectors, measuring devices, current sources, etc., that are used to bring about or measure the desired electrical conditions within an electrochemical cell. It is this portion of the cell through which electrons travel.

Answer 199

A

The process of progressive localized permanent structural change occurring in a material subjected to fluctuating stresses less than the ultimate tensile strength of the material that may culminate in cracks or complete fracture after a sufficient number of fluctuations.

Answer 200

A

The maximum stress that can be sustained for a specified number of cycles without fracture.

Answer 201

A

A current that flows from one conductor to ground or to another conductor as a result of an abnormal connection (including an arc) between the two. A fault current flowing to ground may be called a ground fault current.

Answer 202

A

See Feathering

Answer 203

A

Reducing the thickness of the edges of an undamaged coating film, such as adjacent to a damaged coating or rusted area, by abrasion or sanding to produce a smoothly tapered transitional area prior to recoating.

Answer 204

A

The body-centered cubic crystalline phase of iron or iron-based alloys.

Answer 205

A

Stainless steel whose microstructure at room temperature consists predominantly of ferrite.

Answer 206

A

A steel whose microstructure at room temperature consists predominantly of ferrite.

Answer 207

A

A resin-rich coating or lining into which layers of fiberglass reinforcement have been incorporated to produce mechanical and physical properties superior ro the base resin itself.

Answer 208

A

Corrosion that occurs under some coatings in the form of randomly distributed threadlike filaments.

Answer 209

A

A thin, not necessarily visible layer of material.

Answer 210

A

See Topcoat

Answer 211

A

A small dimple or crater with a visible defect or contaminant in the central area resembling a fish eye that forms in a wet-applied coating.

Answer 212

A

Drainage applied to underground or submerged metallic structures by means of an applied electromotive force or sacrificial anode.

Answer 213

A

Any metallic structure that is not intended as a part of a system under cathodic protection.

Answer 214

A

An accumulation of deposits. (This includes accumulation and growth of marine organisms on a submerged surface and the accumulation of deposition heat exchanger tubing.)

Answer 215

A

Descriptive treatment of fracture, especially in metals, with specific reference to photographs of the fracture surface.

Answer 216

A

A quantitative analysis for evaluating structural reliability in terms of applied stress, crack length, and specimen geometry.

Answer 217

A

See Corrosion Potential

Answer 218

A

The machining characteristics of an alloy to which an ingredient has been introduced to give small broken chips, lower power consumption, better surface finish, and longer tool life.

Answer 219

A

Deterioration at the interface between contacting surfaces as the result of corrosion and slight oscillatory slip between the two surfaces.

Answer 220

A

Type of resin formed by the polymerization or polycondensation of furfuryl, furfuryl alcohol, or other compounds containing a furan ring.

Answer 221

A

A metal that provides sacrificial protection to another metal that is more noble when electrically couples in an electrolyte. This type of anode is the electron source in one type of cathodic protection.

Answer 222

A

Accelerated corrosion of a metal because of an electrical contact with a more noble metal or nonmetallic conductor in a corrosive electrolyte.

Answer 223

A

A pair of dissimilar conductors, commonly metals, in electrical contact in an electrolyte.

Answer 224

A

The electric current flowing between metals or conductive nonmetals in a galvanic couple.

Answer 225

A

A list of metals and alloys arranged according to their corrosion potentials in a given environment.

Answer 226

A

A coating of zinc applied by various processes including hot dipping and electrolytic and mechanical deposition.

Answer 227

A

(1) Applying a coating of zinc. (2) See GALVANIZED COATING

Answer 228

A

Refers to a technique wherein current, continuously varied at a selected rate, is applied to an electrode in an electrolyte.

Answer 229

A

Refers to a galvanostep technique for polarizing an electrode in a series of constant current steps wherein the time duration and current increments or decrements are equal for each step.

Answer 230

A

Refers to a technique wherein an electrode is maintained at a constant current in an electrolyte.

Answer 231

A

Refers to a technique wherein an electrode is polarized in a series of current increments or decrements.

Answer 232

A

Corrosion that is distributed more-or-less uniformly over the surface of a material.

Answer 233

A

An individual crystal in a solid metal or alloy in which the atoms are attained in an orderly pattern.

Answer 234

A

An interface separating two grains.

Answer 235

A

The dislodgement and loss of a grain or grains (crystals) from a metal surface as a result of inter granular corrosion.

Answer 236

A

Deterioration of cast iron wherein the metallic constituents are selectively leached or converted to corrosion products, leaving the graphitic particles intact. [should not be used as a term to describe GRAPHITIZATION.

Answer 237

A

The formation of graphite in iron or steel, usually from decomposition of iron carbide at elevated temperatures. [should not be used as a term to describe GRAPHITIC CORROSION]

Answer 238

A

Cast iron that displays a gray fracture surface as a result of the presence of flake graphite.

Answer 239

A

Small particles of hard material (e.g., iron, steel, or mineral) irregular shapes that are commonly used as an abrasive in abrasive blast cleaning.

Answer 240

A

Abrasive blast cleaning using grit as the abrasive.

Answer 241

A

One or more anodes installed below the earth’s surface for the purpose of supplying cathodic protection.

Answer 242

A

(1) The single oxidation or reduction half reactions in the complete electrochemical cell. (The potential of a half cell can only be calculated from the thermodynamic properties of its components.) [thermodynamic use] (2) Commonly used in the field to refer to a REFERENCE ELECTRODE, but this is not a preferred use.

Answer 243

A

The potential in a given electrolyte of one electrode of a pair relative to a standard state or a reference state. (Potentials can only be measured and expressed as the difference between the half-cell potentials of a pair of electrodes.)

Answer 244

A

Removal of loose rust, loose mill scale, and loose coating by hand chipping, scarping, sanding, and wire brushing. [see SSPC-SP 2]

Answer 245

A

See Curing Agent

Answer 246

A

(1) Resistance of a material to plastic deformation, usually by indentation. (2) The concentration of inorganic polyvalent cations (generally calcium and magnesium) in water.

Answer 247

A

That portion of the base metal that is not melted during brazing, cutting, or welding, but whose microstructure and properties are altered by the heat of these processes.

Answer 248

A

Heating and cooling a solid metal or alloy in such a way as to obtain desired properties. Heating for the sole purpose of hot working is not considered heat treatment.

Answer 249

A

Water cleaning performed at pressures from 34 to 70 MPa (5,000 to 10,000 psig).

Answer 250

A

Waterjetting performed at pressures from 70 to 210 MPa (10,000 to 30,000 psig)

Answer 251

A

A loss of strength and ductility of steel by high-temperature reaction of absorbed hydrogen with carbides in the steel, resulting in decarburization and internal fissuring.

Answer 252

A

A discontinuity in a protective coating that exposes unprotected surface to the environment.

Answer 253

A

Testing of a coating system for holidays using an instrument that applies a voltage between the external surface of the coating and a conductive substrate.

Answer 254

A

An accelerated corrosion of metal surfaces that results from the combined effect of oxidation and reactions with sulfur compounds and other contaminants, such as chlorides, to form a molten salt on a metal surface that fluxes, destroys, or disrupts the normal protective oxide.

Answer 255

A

Applying a coating of zinc by immersion in a bath of molten zinc.

Answer 256

A

Deforming metal plastically under conditions of temperature and strain rate that recrystallization takes place simultaneously with the deformation, thus avoiding any strain hardening. [contract with COLD WORKING]

Answer 257

A

The formation of subsurface planar cavities, called hydrogen blisters, in a metal resulting from excessive internal hydrogen pressure. Growth of near surface blisters in low-strength metals usually results in surface bulges.

Answer 258

A

Embrittlement caused by the presence of hydrogen within a metal or alloy.

Answer 259

A

Stepwise internal cracks that connect adjacent hydrogen blisters on different planes in the metal, or to the metal surface. [also known as stepwise cracking]

Answer 260

A

Overvoltage associated with the liberation of hydrogen gas.

Answer 261

A

Cracking of a metal or alloy under the combined action or tensile stress and the presence of hydrogen in the metal or alloy.

Answer 262

A

A state of resistance to corrosion of a metal in which the metal itself is more thermodynamically stable than its possible corrosion products. (In practical situations, immunity is assumed when the equilibrium concentration of corrosion products is negligible [typically less than 10^-6 mol/L].)

Answer 263

A

Ability of material to resist damage from impact.

Answer 264

A

A form of erosion-corrosion generally associated with the local impingement of a high velocity, flowing fluid against a solid surface.

Answer 265

A

An electric current supplied by a drive employing a power source that is external to the electrode system. (An example is direct current for cathodic protection.)

Answer 266

A

An electrode, suitable for use as an anode when connected to a source of impressed current. (It is often composed of a substantially inert material that conducts by oxidation of the electrolyte and, for this reason, is not corroded appreciably.)

Answer 267

A

A method of applying voltage to an insulated wire through the use of electric pulses (usually 170 to 250 pulses per second) to determine the integrity of the wire’s insulation.

Answer 268

A

A nonmetallic phase such as an oxide, sulfide, or silicate particle in a metal.

Answer 269

A

Coating containing a metallic zinc pigment (typically 75 mass percent zinc or more in the dry film) in an inorganic vehicle.

Answer 270

A

The polarized half-cell potential of an electrode taken immediately after the cathodic protection current is stopped, which closely approximates the potential without IR drop (i.e., the polarized potential) when the current was on.

Answer 271

A

See Galvanostatic

Answer 272

A

See Intergranular Corrosion

Answer 273

A

Corrosion of cast metals that progresses preferentially along paths between dendrites.

Answer 274

A

An intentional metallic connection, between metallic systems in contact with a common electrolyte, designed to control electrical current interchange between the systems.

Answer 275

A

See Stray Current

Answer 276

A

Preferential corrosion at or adjacent to the grain boundaries of a metal or alloy.

Answer 277

A

Stress corrosion cracking in which the cracking occurs along grain boundaries.

Answer 278

A

The formation of isolated particles of oxidation products beneath the metal surface.

Answer 279

A

The swelling or bubbling of a coating usually caused by heating (The term is commonly used in aerospace and fire-protection applications.)

Answer 280

A

An electrically charged atom or group of atoms.

Answer 281

A

The voltage across a resistance when current is applied in accordance with Ohm’s law.

Answer 282

A

Deterioration of wood in contact with iron-based alloys.

Answer 283

A

A line drawn linking all points on a graph that have equal corrosion rates.

Answer 284

A

A graph on which the axes represent environmental parameters (e.g., concentration, temperature, pressure, velocity) and on which one or more isocorrosion curves are drawn.

Answer 285

A

Intergranular corrosion of an alloy along a narrow band adjoining or in contact with a weld.

Answer 286

A

See Exfoliation Corrosion

Answer 287

A

A Number calculated from total dissolved solids, calcium concentration, total alkalinity, pH, and solution temperature that shows the tendency of a water solution to precipitate or dissolve calcium carbonate, wherein an index less than -0.3 indicates that the water tends to be corrosive, while an index greater than +0.3 indicates scale forming potential. [also called Langelier Index or Saturation Index].

Answer 288

A

A paint containing a stable aqueous dispersion of synthetic resin, produced by emulsion polymerization, as the principal constituent of the binder. (Modifying resins may also be present.)

Answer 289

A

(1) the process whereby a wet-applied coating flows out after application to minimize any surface irregularities produced by the process of application. (2) smoothing of a surface by electrochemical or physical means to reduce surface roughness. (3) flattening of sheet or plate.

Answer 290

A

Softening and raising or wrinkling or a previous coat by the application of a subsequent coat.

Answer 291

A

See Diffusion-limited Current Density

Answer 292

A

The direct current flowing in a pipeline

Answer 293

A

A coating or layer of sheet material adhered to or in intimate contact with the interior surface of a container used to protect the container against corrosion by its contents and/or to protect the contents of the container from contamination by the container material.

Answer 294

A

Environmental cracking caused by contact with a liquid metal.

Answer 295

A

An electrochemical cell created on a metal surface because of a difference in potential between adjacent areas on that surface.

Answer 296

A

Corrosion at discrete sites (e.g., pitting or crevice corrosion).

Answer 297

A

Current flowing through the earth between an anodic and a cathodic area that returns along an underground metallic structure. (Usually used only where the areas are separated by considerable distance and where the current flow results from concentration-cell action.)

Answer 298

A

Alloy steel with a total alloying element content of less than approximately 5 mass percent.

Answer 299

A

Steel having less than 0.30 mass percent carbon and no intentional alloying additions.

Answer 300

A

Water cleaning performed at pressures less than 34 MPa (5,000 pig). [also called Power Washing or Pressure Washing]

Answer 301

A

See Luggin-Haber Probe

Answer 302

A

A device used in measuring the potential of an electrode with a significant current density imposed on its surface. (The probe minimizes the IR drop that would otherwise be included in the measurement and without significantly disturbing the current distribution on the electrode.) [also called LUGGIN CAPILLARY or LUGGIN PROBE]

Answer 303

A

See Luggin-Haber Probe

Answer 304

A

Corrosion of a metal embedded in porous media (e.g., concrete or soil) caused by concentration or galvanic cells that exist on a scale at least at large at the smallest major dimension of the corroding item (e.g., the diameter of a bar or pipe).

Answer 305

A

White cast iron that is thermally treated to convert most or all of the cementite to graphite (temper carbon).

Answer 306

A

A hard, body-centered cubic phase of iron supersaturated with carbon, usually produced by rapid cooling.

Answer 307

A

Steel in which a microstructure of martensite can be attained by quenching at a cooling rate fast enough to avoid the formation of other microstructures.

Answer 308

A

(1) Aromatic resin of the mastic tree, commonly used in lacquers and varnishes. (2) A material of relatively viscous, paste-like consistency that can be poured when heated but often requires mechanical manipulation (e.g., using a trowel) to apply, which dries or cures to form a thigh protective coating. (Mastics usually contain fillers, such as powdered lime or graded mineral aggregate, to produce the desired consistency.)

Answer 309

A

Accelerated deterioration of a metal or alloy exposed to a carbonaceous or nitrogenous gas at elevated temperatures that forms a dust-like corrosion product. =

Answer 310

A

The coating of a surface with a thin metal layer by thermal spraying, hot dipping, or caecum deposition.

Answer 311

A

Corrosion affected by the presence or activity, or both, or microorganisms.

Answer 312

A

The oxide layer formed during hot fabrication or heat treatment of metals.

Answer 313

A

A thin tack coat, applied as a mist of spray, used to improve adhesion of a new coat to an existing partially cured coat or to displace air in a porous substrate.

Answer 314

A

A potential resulting from two or more electrochemical reactions occurring simultaneously on one metal surface.

Answer 315

A

A measure of the stiffness or rigidity of a material. It is actually the ration of stress to strain in the elastic region of a material if determined by a tension or compression test. [also called Young’s Modulus or Coefficient of Elasticity]

Answer 316

A

That portion or a structure that is located below the interface of a water body with its respective sea-, lake-, or riverbed and is covered by mostly solid material.

Answer 317

A

Current drainage from an underground or submerged metallic structure to a more negative (more anodic) structure, such as the negative bus of a trolley substation.

Answer 318

A

An abrasive blast cleaned steel surface that is free of all visible contaminants and foreign matter, but may have some random staining on no more than 5 percent of the surface area. [See NACE No. 2/SSPC-SP 10 for detailed specification.]

Answer 319

A

A point of connection between the cathodic protection relative cable and the protected structure.

Answer 320

A

An equation that expresses the potential of an electrochemical reaction in terms of the activities of its products and reactants.

Answer 321

A

The diffusion layer at the surface of an electrode in which the concentration of a chemical species is assumed to vary linearly from the value in the bulk solution to the value at the electrode surface.

Answer 322

A

The absorption and diffusion of nitrogen in metallic materials (most commonly ferrous alloy.) Typical processes for intentional nitriding include, but are not limited to, liquid nitriding, gas nitriding, and ion or plasma nitriding.)

Answer 323

A

The positive (increasingly oxidizing) direction of electrode potential.

Answer 324

A

A metal with a standard electrode potential more positive than that hydrogen.

Answer 325

A

A potential more positive than the standard hydrogen potential.

Answer 326

A

See Ductile Cast Iron

Answer 327

A

Heating a ferrous alloy to a suitable temperature above the transformation range (austenitizing), holding at temperature for a suitable time, and then cooling in still air to a temperature substantially below the transformation range.

Answer 328

A

An electrochemical cell created at a localized site on a metal surface that has been partially obstructed from the bulk environment.

Answer 329

A

The degree of obstruction to the transmission of visible light or to which a material obscures a substrate.

Answer 330

A

See Corrosion Potential

Answer 331

A

(1) The dimpled appearance of a dried coating resembling the surface of a navel orange. (2) The rough appearance of a metal surface resulting from large grain size deformation.

Answer 332

A

Coating containing metallic zinc pigment (typically 75 mass percent zinc or more in the dry film) in an organic vehicle.

Answer 333

A

The difference in potential of an electrode between its equilibrium and steady-state values when current is applied.

Answer 334

A

(1) Loss of electrons by a constituent of a chemical reaction. (2) Corrosion of a material that is exposed to an oxidizing gas at elevated temperatures.

Answer 335

A

The potential of a reversible oxidation-reduction reaction in a given electrolyte reported on the standard hydrogen electrode scale. [also called REDOX POTENTIAL]

Answer 336

A

See Differential Aeration Cell

Answer 337

A

A pigmented liquid or resin applied to a substrate as a thin layer that is converted to a solid film after application. (it is commonly used for decoration or protection.)

Answer 338

A

See Coating System

Answer 339

A

See Dealloying

Answer 340

A

The minimum concentration of a more noble component in an alloy above which dealloying does not occur in a specific environment.

Answer 341

A

The process in metal corrosion by which metals become passive. [See PASSIVE]

Answer 342

A

See Primary Passive Potential

Answer 343

A

A corrosion inhibitor that reduces the corrosion rate of a metal by changing reactions at the metal surface to cause the formation of a protective corrosion product, resulting in a positive shift in corrosion potential.

Answer 344

A

(1) the state of a metal surface characterized by low corrosion rates in a potential region that is strongly oxidizing for the metal. (2) the positive direction of electrode potential.

Answer 345

A

The state of being passive.

Answer 346

A

(1) The corrosion product film, usually green, that forms on the surface of copper and copper alloys exposed to the atmosphere. (2) A corrosion product find on the weathered surface of any metal.

Answer 347

A

Detachment or partial detachment of a coating from the substrate or undercoat.

Answer 348

A

The negative logarithm of the hydrogen ion activity written as: pH=-log⬇️10(a⬇️H⬆️+)
Where: (a⬇️H⬆️+) = hydrogen ion activity = the molar concentration of hydrogen ions multiplied by the mean ion-activity coefficient.

Answer 349

A

Treatment of steel or other metals with an aqueous phosphate, phosphoric acid solution, or both to form an adherent phosphate surface layer that can serve as a good base for subsequent coating application. [also known as PHOSPHATIZING]

Answer 350

A

See Phosephating

Answer 351

A

(1) Treating a metal or alloy in a chemical bath to remove scale and oxides (e.g., rust) from the surface. (2) complete removal of rust and mill scale by acid pickling, duplex pickling, or electrolytic pickling. [See SSPC-SP 8.]

Answer 352

A

A chemical bath, usually an acid solution, used for pickling.

Answer 353

A

A solid substance, generally in fine powder form, that is insoluble in the vehicle of a formulated coating material. It is used to impart color or other specific physical or chemical properties to the coating.

Answer 354

A

A mint hole through a coat or coats that exposes an underlying coat or the substrate.

Answer 355

A

See Structure-to-electrolyte Potential

Answer 356

A

See Structure-to-electrolyte Potential

Answer 357

A

A surface cavity with depth equal to or greater than the minimum dimension at the opening. [contrast with crater]

Answer 358

A

Localized corrosion of a metal surface that is confined to a small area and takes the form of cavities called pits.

Answer 359

A

The ratio of the depth of the deepest pit resulting from corrosion divided bu the average penetration as calculated from mass loss.

Answer 360

A

A number calculated using a weighted formula typically based on the chromium (Cr), molybdenum (Mo), nitrogen (N), and sometimes tungsten (W) content of an alloy, developed to rank the pitting and crevice corrosion resistance of stainless steels and some nickel-based alloys. (Larger numbers indicate increased resistance to pitting and crevice corrosion in seawater and other halide-containing aqueous environments.) (For example, NACE MR0175/ISO 15156 uses PREN = Cr + 3.3 {Mo + o.5W} + 16N, where each element symbol represents the mass percent of that element in the alloy.

Answer 361

A

Permanent deformation caused bu stressing beyond the elastic limit.

Answer 362

A

The ability of material to deform permanently (novelistically) without fracturing.

Answer 363

A

The change from the corrosion potential as a result of current flow across the electrode/electrolyte interface.

Answer 364

A

The reciprocal of polarization resistance.

Answer 365

A

A DC decoupling device consisting of two or more pairs of inert metallic plates immersed in an aqueous electrolyte. The electrical characteristics of the polarization cell are high resistance to DC potentials and low AC impedance.

Answer 366

A

A plot of current density versus electrode potential for a specific electrode/electrolyte combination.

Answer 367

A

The change in electrode potential with time resulting from the interruption of applied current.

Answer 368

A

The slope (dE/di) at the corrosion potential of a potential (E) - current density (i) curve. (It is inversely proportional to the corrosion current density when the polarization resistance technique is applicable.)

Answer 369

A

(1) (general use) the potential across the electrode/electrolyte interface that is the sum of the corrosion potential and the applied polarization. (2) (cathodic protection use) The potential across the structure/electrolyte interface that is the sum of the corrosion potential and the cathodic polarization.

Answer 370

A

Type of resin formed by the condensation of polyphasic and mono basic acids with polyhedric alcohols.

Answer 371

A

A polymer formed by reaction of an isocyanate with a poll (hydroxyl-containing material). (When used as a coating binder, it generally produces a tough, durable, glossy protective coating with good chemical ultraviolet light resistance.)

Answer 372

A

Heating and cooling a weldment in such a way as to obtain desired properties.

Answer 373

A

A graphical method of representing the regions of thermodynamic stability of species for metal/electrolyte systems. [also known as POURBAIX DIAGRAM]

Answer 374

A

Refers to a technique wherein the potential of an electrode with respect to a reference electrode is varied at a selected rate by application of a current through the electrolyte.

Answer 375

A

See Potentiodynamic

Answer 376

A

Refers to potentiostep technique for polarizing an electrode in a series of constant potential steps where in the time duration and potential increments or decrements are equal for each step.

Answer 377

A

an instrument for automatically maintaining an electrode in an electrolyte at a constant potential or controlled potentials with respect to a suitable reference electrode.

Answer 378

A

Refers to a technique for maintaining a constant electrode potential.

Answer 379

A

Refers to a technique wherein an electrode is polarized in a series of potential increments or decrements.

Answer 380

A

The maximum elapsed time during which a coating can be effectively applied after all components of the coating have been thoroughly mixed.

Answer 381

A

See Deposit Corrosion

Answer 382

A

See Potential-pH Diagram

Answer 383

A

Removal of loose rust, loose mill scale and loose coating bu power tool chipping, descaling, sanding, wire brushing, and grinding. [See SSPC-SP 3]

Answer 384

A

Hardening caused by the precipitation of a constituent from a supersaturated solid solution.

Answer 385

A

The potential corresponding to the maximum active current density (critical anodic current density) of an electrode that exhibits active-passive corrosion behavior.

Answer 386

A

See Primer

Answer 387

A

A coating material intended to be applied as the first coat on an uncoated surface. The coating is specifically formulated to adhere to and protect the surface as well as to produce a suitable surface for subsequent coats. [also referred to a as PRIME COAT]

Answer 388

A

An instrument for measuring and recording the topographical profile of a surface.

Answer 389

A

The most noble potential at which pitting or crevice corrosion, or both, will not propagate in a specific environment.

Answer 390

A

A coating applied to a surface to protect the substrate from corrosion.

Answer 391

A

Quench hardened and then tempered.

Answer 392

A

See Oxidation-reduction Potential.

Answer 393

A

Gain of electrons by a constituent of a chemical reaction.

Answer 394

A

An electrode having a stable and reproducible potential, which is used in the measurement of other electrode potentials.

Answer 395

A

See Reference Electrode

Answer 396

A

(1) glass cloth, chopped fibers, or mat used to provide additional tensile and flexural strength and other properties to a coating or lining. (2) bars or fibers added to concrete to enhance its mechanical properties.

Answer 397

A

The ratio, expressed as a percentage, go the amount of water vapor present in a given volume of air at a given temperature.

Answer 398

A

A location on the earth far enough from the affected structure that the soil potential gradients associated with currents entering the earth from the affected structure are insignificant.

Answer 399

A

Stress present in a component free from external forces or thermal gradients.

Answer 400

A

A clear to translucent, solid or semisolid, viscous organic substance, often of relatively high molecular mass, which exhibits a tendency to flow when subjected to stress and usually has a softening or melting range. (Natural resins originate from secreting or melting range. (Natural resins originate from secretions of certain plants and insects. Synthetic resins are physically similar polymerized synthetic materials, either thermoplastic or thermosetting, which are used to form plastics. Resins are commonly used as the binder in various paints, coatings, adhesives, and synthetic plastics.)

Answer 401

A

The electrical resistance between opposite faces of a unit cube of material.

Answer 402

A

Corrosion potential after time transients have subsided.

Answer 403

A

See Equilibrium Potential

Answer 404

A

An incompletely deoxidized steel. [also called RIMMING STEEL]

Answer 405

A

See Rimmed Steel

Answer 406

A

(1) That section of pipeline extending from the ocean floor up to an offshore structure. (2) The vertical tube in a steam upward. (3) A large-diameter pipe or duct in a fluidized catalytic cracking unit into which the hydrocarbon feed is injected to mix with a stream of hot catalyst and steam and through which the resulting reaction mixture flows upward.

Answer 407

A

Hardness value, measured in accordance with ISO 6508-1 or Test Methods E18, obtained using a diamond cone indenter and a force of 1.471 N.

Answer 408

A

A reddish-brown find powder consisting primarily of iron oxide particles.

Answer 409

A

Corrosion product consisting of various iron oxides and hydrated iron oxides. (This term properly applies only to iron and ferrous alloys.)

Answer 410

A

Discoloration indicating the beginning of rusting.

Answer 411

A

Scrubbing a mixture of a cement mortar over the concrete surface using a cement sack, gunny sack, or sponge rubber float.

Answer 412

A

See Galvanic Anode

Answer 413

A

Reduction of corrosion of a metal in an electrolyte by electrically connecting the metal to a galvanic anode (a form of cathodic protection).

Answer 414

A

Nonuniform downward flow of a wet-applied coating under the force of gravity that results in an uneven coating having a thick lower edge.

Answer 415

A

Portion of material taken from a larger quantity in a manner intended to be representative of whole, typically used for test purposes.

Answer 416

A

(1) the formation at high temperatures of which corrosion-product layers on a metal surface. (2) The deposition of water-insoluble constituents on a metal surface.

Answer 417

A

An electron optical device that scans a beam of electrons across a surface and collects the resulting electrons or photons to form an image whose contract is determined by topography, elemental composition, or other properties.

Answer 418

A

(an obsolete term) A form of environmental cracking of brass in the atmosphere.

Answer 419

A

See Dealloying

Answer 420

A

See Dealloying

Answer 421

A

A metallurgical state caused by certain heating, cooling, or cold working conditions that results in precipitation of constituents (e.g., carbides in a stainless steel) at grain boundaries, thereby causing an alloy to be susceptible to inter granular corrosion or inter granular stress corrosion cracking in a specific environment in which the alloy would normally exhibit corrosion resistance.

Answer 422

A

A heat treatment that produces sensitization.

Answer 423

A

One or more anodes installed wither vertically or horizontally at a nominal depth of less than 15 m (50 ft) for the purpose of supplying cathodic protection current.

Answer 424

A

The maximum length of time packaged materials (e.g., coating materials) can be stored, at specified conditions, and remain in usable condition.

Answer 425

A

(1) Protecting; protective cover against mechanical damage. (2) Preventing or diverting cathodic protection current from its natural path.

Answer 426

A

One or more coats applied in a shop or plant prior to shipment to the site of erection or fabrication.

Answer 427

A

Abrasive blast cleaning using metallic (usually steel) shot as the abrasive.

Answer 428

A

Inducing compressive stresses in the surface layer of material by bombarding it with a selected medium (usually steel shot) under controlled conditions.

Answer 429

A

An extremely brittle Fe-Cr phase that can form at elevated temperatures in Fe-Cr, Fe-Cr-Ni and Ni-Cr-Fe alloys.

Answer 430

A

A deformation process involving shear motion of a specific set of crystallographic planes.

Answer 431

A

An experimental technique for evaluating susceptibility to environmental cracking. It involves pulling the specimen to failure in uniaxial tension at a controlled slow strain rate while the specimen is in the test environment and examining the specimen for evidence of environmental cracking.

Answer 432

A

Oil or grease coatings used to provide temporary protection against atmospheric corrosion.

Answer 433

A

Single crystalline phase containing two or more elements.

Answer 434

A

Heating a metal to a suitable temperature holding at that temperature long enough for one or more constituents to enter into solid solution, then cooling rapidly enough to retain the constituents in solution.

Answer 435

A

Removal of oil, grease, dirt, soil, salts, and contaminants using organic solvents or other cleaners such as vapor alkali, emulsion, or steam. [See SSPC-SP 1].

Answer 436

A

The spontaneous chipping, fragmentation, or separation of a surface or surface coating.

Answer 437

A

A high-voltage electrical test in which a spark is used to detect a discontinuity in a coating.

Answer 438

A

Reflection of light, as from a mirror, as opposed to diffuse reflection in all directions.

Answer 439

A

The portion of a marine structure that is intermittently wetted by waves, wind-blown water spray. and tidal action. (Surfaces that are wetted only during major storms are not included.)

Answer 440

A

Prepared portion of a sample or coupon upon which a test is intended to be performed. [also known as test specimen.]

Answer 441

A

The average area covered by a unit volume of coating material at a specified dry film thickness. (Spreading rate is usually specified as square meters per liter or square feet per gallon.)

Answer 442

A

Steel containing 10.5 mass percent or more chromium, possibly with other elements added to secure special properties.

Answer 443

A

The reversible potential for an electrode process when all products and reactants are at unit activity reported on the standard hydrogen electrode scale.

Answer 444

A

Water of sufficient purity and quality that does not impose additional contaminants on the surface being cleaned and does not contain sediments or other impurities that are destructive to the proper functioning of water jetting equipment.

Answer 445

A

Small particles of steel with spherical shape that are commonly used as an abrasive blast cleaning or as a selected medium for shot peening.

Answer 446

A

The potential difference between two points on the earth’s surface separated by a distance of one human step, which is defined as one meter, determined in the direction of maximum potential gradient.

Answer 447

A

See Hydrogen-induced Cracking

Answer 448

A

Current flowing through pats other than the intended circuit.

Answer 449

A

Corrosion resulting from stray current.

Answer 450

A

Cracking of a material produced by the combined action of corrosion and sustained tensile stress (residual or applied). [See environmental cracking.]

Answer 451

A

Heating a metal to a suitable temperature, holding at that temperature long enough to reduce residual stresses, and then cooling slowly enough to minimize the development of new residual stresses.

Answer 452

A

The potential difference between the surface of a buried or submerged metallic structures, or sections of the same structure, in a common electrolyte.

Answer 453

A

The surface area of a marine structure that is always covered with water and extends downward from the splash zone and includes that portion of the structure below the mud line.

Answer 454

A

See Internal Oxidation

Answer 455

A

The reaction of a metal or alloy with a sulfur-containing species to produce a sulfur compound that forms on or beneath the surface of the metal or alloy.

Answer 456

A

Cracking of a metal under the combined action of tensile stress and corrosion in the presence of water and hydrogen sulfide (a form of hydrogen stress cracking).

Answer 457

A

Change in the potential on the surface of the ground with respect to distance.

Answer 458

A

The irregular peak and valley profile on a bare surface that can result from operations such as abrasive blast cleaning or power tool cleaning. [also called another pattern]

Answer 459

A

See brush-off Blast Cleaned Surface

Answer 460

A

A thin wet coat applied to the surface that is allowed to dry just until it is tacky before application of thicker coats without sags or runs.)

Answer 461

A

A plot of the relationship between the change in potential (E) and the logarithm of the current density (log i) of an electrode when it is polarized int the anodic or cathodic direction, or both, from its open circuit potential.

Answer 462

A

The slope of the non vertical, non horizontal straight-line portion of the E log i curve on a Tafel plot.

Answer 463

A

A test in which an adhesive tape is applied to a cured coating, generally after making cuts through the coating to the substrate, and rapidly removed to evaluate the adhesive bond of the coating to the substrate.

Answer 464

A

Surface discoloration of a metal resulting from formation of a film of corrosion product.

Answer 465

A

Heat treatment by heating to a temperature below the lower critical temperature for the purpose of decreasing the hardness and increasing the toughness of hardened steel, hardened cast iron, and sometimes normalized steel.

Answer 466

A

See Specimen

Answer 467

A

A high-temperature process by which finely divided metallic or nonmetallic materials are deposited in a molten or semimolten condition for form a coating on a surface when cooled.

Answer 468

A

Corrosion resulting from an electrochemical cell caused by a thermal gradient.

Answer 469

A

A polymeric material (typically a resin) capable of being (a) repeatedly softened by heat and hardened by cooling or (b) [not a preferred term, but used for coatings] dissolved by solvent and reformed upon solvent evaporation. [contract with THERMOSET]

Answer 470

A

A coating with a thermoplastic binder.

Answer 471

A

A polymeric material (typically a resin) that undergoes a chemical cross-linking reaction (by mechanisms involving heat, oxidation, catalysis, light [often ultraviolet], electron beam, or chemical additive) leading to a relatively infusible state.

Answer 472

A

A coating with a thermoset binder.

Answer 473

A

The relationship between the current density at a point on a surface and its distance from the counter electrode. The greater the ratio of the surface resistivity shown by the electrode reaction to the volume resistivity of the electrolyte, the better is the throwing power of the process.

Answer 474

A

That portion of a marine structure that is intermittently wetted by tidal action.

Answer 475

A

The final coat of a coating system. [also referred to as FINSIH COAT]

Answer 476

A

The potential difference between metallic structure and a point on the earth’ s surface separated by a distance equal to the normal maximum horizontal reach of a human (approximately 1.0 m [3.3 ft])

Answer 477

A

The ability of a material to absorb energy and deform plastically before fracturing.

Answer 478

A

The region of an anodic polarization curve, more positive than the passive potential range, in which there is a significant increase in current density (increased metal oxidation) as the potential becomes more positive.

Answer 479

A

A mound of corrosion product and deposit capping a region of localized metal loss.

Answer 480

A

The formation of localized corrosion products scattered over the surface in the form of knob-like mounds called tubercles.

Answer 481

A

The maximum stress that a material can sustain without failing from tensile overload.

Answer 482

A

Waterjetting performed at pressures above 210 MPa (30,000 psig).

Answer 483

A

See Filiform Corrosion

Answer 484

A

Corrosion that proceeds at exactly the same rate over the surface of a material. (This is the assumption when calculating corrosion rate or corrosion loss from mass loss or electrochemical measurements. This term should not be used instead of general corrosion to describe an observed surface distribution of corrosion).

Answer 485

A

A hot deformation process to cause a thickening of metal by compressive forces.

Answer 486

A

Not a preferred term, but commonly used to refer to POLYURETHANE.

Answer 487

A

The liquid portion of a formulated coating material.

Answer 488

A

Hardness value, measured in accordance with ISO 6507-1 or Test Method E92, obtained using a diamond pyramid indenter and one of a variety of possible applied loads.

Answer 489

A

(1) A holiday, hole, or skip in a coating. (2) A hole in a casting or weld deposit usually resulting form shrinkage during cooling.

Answer 490

A

A thin, inhibiting, or passivating primer, usually formulated with chromate or phosphate pigment in a synthetic resin (e.g., polyvinyl butyral) binder.

Answer 491

A

Use of standard jetting water discharge from a nozzle at pressures of 70 MPa (10,000 psig) or greater to prepare a surface for coating or inspection.

Answer 492

A

An external coating applied to a pipeline to contract buoyancy.

Answer 493

A

Join two or more pieces of material by applying heat and/or pressure with or without filler material, to produce a union through localized fusion of the substrates and solidification across the interfaces.

Answer 494

A

(not a preferred term) inter granular corrosion, usually of stainless steels or certain nickel alloys, that occurs as the result of sensitization in the heat-affected zone during the welding operation.

Answer 495

A

(1) An assembly of components joined by welding. (2) [for metals] the weld metal, the heat-affected zone, and the adjacent parent metal.

Answer 496

A

That portion of a weldment that has been molten during welding.

Answer 497

A

Device for measuring wet film thickness of a coating.

Answer 498

A

The thickness of a coating measured immediately after application before and appreciable solvent has evaporated or drying has taken place.

Answer 499

A

A low-voltage electrical test suitable for detecting holidays in thin-film coatings.

Answer 500

A

Cast iron that displays a white fracture surface.

Answer 501

A

An abrasive blast cleaned steel surface that is free of all visible contaminants, foreign matter, and staining. [See NACE Np. 1/SSPC-SP 5 for detailed specification.]

Answer 502

A

The white powdery corrosion product that can form on zinc, zinc-coated, or aluminum-based alloy surfaces. [See RUST.]

Answer 503

A

The test or specimen electrode in an electrochemical cell.

Answer 504

A

Formation of a surface appearance in a coating resembling the skin of a dried prune, usually caused by application shortcomings.

Answer 505

A

Describes a metal in the solid condition formed to a desired shape by working (e.g., rolling, extruding, forgoing), usually at an elevated temperature.

Answer 506

A

The stress on a material at which the first significant permanent or plastic deformation occurs without an increase in stress. In some materials, particularly annealed low-carbon steels, there is a well-defined yield point from the straight line defining the modulus of elasticity.

Answer 507

A

The stress at which a material exhibits a specified deviation from the proportionality of stress to strain. The deviation is expressed in terms of strain by either offset method (usually at strain of 0.2 percent) or the total-extension-under-load method (usually at a strain of 0.5 percent).

Answer 508

A

See Electrokinetic Potential

Brainscape's Knowledge GenomeTM

Terminology and Acronyms Flashcards

Relating to Corrosion

Brainscape's Knowledge Genome^TM