Theory Flashcards
(155 cards)
1
Q
The study of the nature, behavior, and use of materials applied to science and technology
A
Material Science
2
Q
It involves investigating the relationships that exist between the structures and properties of materials
A
Material Science
3
Q
An interdisciplinary field applying the properties of matter to various areas of science and engineering.
A
Material Science
4
Q
Designing or engineering the structure of a material to produce a predetermined set of properties
A
Material Engineering
5
Q
The —— of a material usually relates to the arrangement of its internal components.
A
structure
6
Q
A ——— is a material trait in terms of the kind and magnitude of response to a specific imposed stimulus.
A
property
7
Q
Classification of Materials
A. Fundamental Classes
1. ________________________________
2. ________________________________
3. ________________________________
A
- Metallic
- Ceramic
- Polymeric
8
Q
B. Major Classes
1. ________________________________
2. ________________________________
3. ________________________________
4. ________________________________
5. ________________________________
A
- Metallic
- Ceramic
- Polymeric
- Composite
- Advance Materials
9
Q
What are the main or fundamental classes of engineering materials?
A. Composite materials and noncomposite materials
B. Metallic materials, polymeric materials and ceramic materials
C. Metallic materials, nonmetallic materials, polymeric materials and ceramic materials
D. Metallic materials and nonmetallic materials
A
B. Metallic materials, polymeric materials and ceramic materials
10
Q
Materials in this group are composed of one or more metallic elements, and often also nonmetallic elements in relatively small amounts.
A
Metals and alloys
11
Q
Atoms in ——– and their alloys are arranged in a very orderly manner, and in comparison to the ceramics and polymers, are relatively dense
A
metals
12
Q
Characteristics of Metals
A
- Stiff and strong
- Ductile
- Resistant to fracture
- Extremely good conductors of electricity and heat
- Not transparent to visible light
- Has a lustrous appearance
- Some has magnetic prope
13
Q
The addition of other elements into a metal
A
Alloying
14
Q
Composition of Brass
A
Copper and zinc
15
Q
Composition of Bronze
A
copper, zinc, tin
16
Q
Composition of Pewter
A
tin, copper, bismuth, antimony
17
Q
Composition of cast iron
A
iron, carbon, manganese, silicon
18
Q
Composition of steel
A
iron, carbon
19
Q
Composition of stainless steel
A
iron, chromium, nickel
20
Q
The traditional process for making metallic components begins with melting of the metal or alloy.
A
Casting
21
Q
If the molten mass is poured into a mold of some type and solidified, the process is called
A
casting
22
Q
These materials have a large number of non-localized electrons, as an effect are very good conductors of electricity and heat. They are strong yet deformable, and extensively used in structural applications.
A. Polymers C. Metals
B. Ceramics D. Composites
A
C. Metals
23
Q
Which of the following metals has the highest electrical conductivity?
A. Zinc C. Gold
B. Copper D. Aluminum
A
B. Copper
24
Q
Which of the following is not a refractory metal?
A. Lead C. Tungsten
B. Niobium D. Tantalum
A
A. Lead
25
What type of materials behaves like iron when placed in a magnetic field?
A. Crystals C. Amorphous
B. Ferromagnetic D. Metalloids
B. Ferromagnetic
26
This element is used in modern, super strong permanent magnets because of their high coercivities
A. beryllium C. yttrium
B. neodymium D. alnico
B. neodymium
27
This metal is alloyed with steel to give it corrosion resistance properties, resulting in stainless steel.
A. vanadium C. molybdenum
B. magnesium D. chromium
D. chromium
28
What refers to the property of a substance to be repelled by a magnet due to the presence of paired electrons?
A. Paramagnetic C. Diamagnetic
B. Ferromagnetic D. Ferrimagnetic
C. Diamagnetic
29
What metal has the lowest boiling temperature?
A. Mercury C. Steel
B. Iron D. Molybdenum
A. Mercury
30
Which of the following is true about refractory metals?
A. Resistant to oxidation
B. Resistant to corrosion
C. Resistant to heat
D. Resistant to sun’s rays
C. Resistant to heat
31
Comes from the Greek word keramikos, which means “burnt stuff”.
Ceramics
32
The desirable properties of these materials are normally achieved through a high-temperature heat treatment process called
Firing
33
Compounds between metallic and nonmetallic elements
ceramics
34
They are most frequently oxides, nitrides, and carbides
ceramics
35
Characteristics of Ceramics
- High melting point
- High hardness
- Extremely brittle
- Highly susceptible to fracture
- Typically insulative to the passage of heat and electricity
- More resistant to high temperatures and harsh environments than metals and polymers - May be transparent, translucent, or opaque
36
Defined as supercooled liquids because they do not crystallize when cooled below their melting points.
Glass
37
The principal component of the white wares and structural clay products
Clay
38
The materials that are employed at elevated temperatures and often in reactive environments
Refractories
39
Used to wear, grind, or cut away other material, which necessarily is softer
abrasive ceramics
40
Diamond, silicon carbide, tungsten carbide, corundum, and silica sand are the most common examples
abrasive ceramics
41
The characteristic feature of these materials is that when mixed with water, they form a paste that subsequently sets
and hardens
cements
42
What are compounds of metallic and nonmetallic elements called?
A. Ceramics C. Semiconductor
B. Metalloids D. Alloys
A. Ceramics
43
This refers to lowering the temperature of a liquid below its melting point before it becomes solid.
A. Sub cooling C. Super cooling
B. Supercritical D. Subcritical
C. Super cooling
44
Oxides, nitrides and carbides are main compositional classes of what type of material?
A. ceramics C. composites
B. metals D. polymers
A. ceramics
45
The process where a physical mixture of carbide and powdered metal is heated in order to solidify the powder into single piece.
A. Vitrification C. Sintering
B. Ceramication D. Polymerization
C. Sintering
46
_________ are composed of ceramics and metals
A. Cement C. Glass
B. Metal matrix D. Cermets
D. Cermets
47
The process of gluing the powders together with glasses to form other ceramic materials.
A. Vitrification C. Sintering
B. Ceramication D. Polymerization
A. Vitrification
48
Ceramic materials are found on ________ on the periodic table
A. Group 1 – 5 C. Group 4B
B. Group 3 – 12 D. Group 1A
A. Group 1 – 5
49
_______ materials are approximately considered to be those having a fracture strain of less than about 5%.
A. Ceramic C. Ductile
B. Brittle D. Malleable
B. Brittle
50
Which of the following is not a ceramic?
A. Glass C. Diamond
B. Graphite D. Carbon
D. Carbon
51
include the familiar plastic and rubber materials
Polymers
52
Many of them are organic compounds that are chemically based on carbon, hydrogen, and other nonmetallic elements (O,N, and Si)
Polymers
53
They have very large molecular structures, often chain like in nature that have a backbone of carbon atoms
Polymers
54
Characteristics of Polymers
- Extremely ductile and pliable (i.e., plastic), which means they are easily formed into complex shapes.
- Relatively inert chemically and unreactive in a large number of environments.
- Tendency to soften and decompose at modest temperatures
- Low electrical conductivities and are nonmagnetic.
55
is the basic repeating unit of a polymer
monomer or mers
56
Refers to the small molecule from which a polymer is synthesized
monomers
57
When all the repeating units along a chain are of the same type
homopolymer
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Chains may be composed of two or more different repeat units
Copolymer
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Polymer structures that are those in which the repeat units are joined together
end to end in single chains.
Linear
60
Polymers synthesized in which side - branch chains are connected to the main ones
branched
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Adjacent linear chains are joined one to another at various positions by covalent bonds
cross-linked
62
Multifunctional monomers forming three or more active covalent bonds, make three-dimensional networks
Network
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The term “blend” refers to materials that are mixture of _______?
A. two or more polymers
B. metal and non – metal
C. a polymeric and a ceramic
D. two or more ceramic
A. two or more polymers
64
Polymer comes from Greek words poly which means many and meros which means _________.
A. metal C. material
B. part D. plastic
B. part
65
Which of the following plastics does not burn but rather extinguishes itself?
A. polyester C. acrylic
B. nylon D. propylene
B. nylon
66
_____________ refers to the strong primary chemical bonds which forms some of the polymeric materials.
A. Polymerization C. Cross – linking
B. Vulcanization D. Copolymerization
C. Cross – linking
67
In polymers, what refers to a large molecule with alternating mers?
A. Copolymer C. Cross – linking
B. Monomer D. Vulcanization
A. Copolymer
68
Polymers are materials that are found on __________ on the periodic table. [OCT 2012 ECE Board Exam]
A. Group 1 – 5 C. Group 4B
B. Group 3 – 12 D. Group 1A
C. Group 4B or 4A
69
The average number of mers in the molecule of a polymer is known as:
A. Degree of polymerization
B. Polymerization coefficient
C. Copolymerization constant
D. All of the choices are correct
A. Degree of polymerization
70
Wood is composed of chains of cellulose molecules bonded together by another natural polymer called
_______.
A. cellulose C. latex
B. plastic D. lignin
D. lignin
71
Composed of two (or more) individual materials, which come from the metals, ceramics, and polymers
Composite
72
Materials that are utilized in high-technology applications - Semiconductors, biomaterials, and materials of the future
Advanced materials
73
Have electrical properties that are intermediate between
electrical conductors and insulators
Semi conductors
74
Are employed in components implanted into the human body for replacement of diseased or damaged body parts.
Biomaterials
75
Materials of the Future uses
- Smart (intelligent) materials
- Nanoengineered materials \
- Carbon nanotubes
76
Materials composed of more than one material type and are designed to display a combination of the best characteristics of each component material.
A. Polymers C. Metals
B. Ceramics D. Composites
D. Composites
77
A composite material composed of large ceramic particles distributed over a ceramic binder, used chiefly in structural applications.
A. cement C. concrete
B. nanofiber D. fiberglass
C. concrete
78
These are materials, commonly used as actuators, which after having been deformed revert back to their original shapes when temperature is changed.
A. Shape memory alloys
B. Piezoelectric materials
C. Magnetorestrictive materials
D. Electrorheological materials
A. Shape memory alloys
79
Materials that have electrical properties that are intermediate between the metals or metal alloys and ceramics or polymers
A. metalloid C. insulator
B. porcelain D. semiconductor
D. semiconductor
80
What is the strongest material?
A. Carbon nanotubes C. Fullerenes
B. Shape memory alloys D. Diamond
A. Carbon nanotubes
81
A device used in biotelemetry for monitoring the physiologic activity of an animal, such as pH values of stomach acid
A. radio pill C. biomed
B. biotelemeter D. pH meter
A. radio pill
82
A material property that relate deformation to an applied load or force
Mechanical Property
83
The stimulus is an electric field on a material
Electrical property
84
Represented in terms of heat capacity and thermal conductivity
Thermal property
85
the response of a material to the application of a magnetic field
magnetic property
86
the stimulus is electromagnetic or light radiation
optical property
87
relate to the chemical reactivity of materials
deteriorative property
88
The _____________, sometimes called the breakdown strength, represents the magnitude of an electric field necessary to produce breakdown.
A. Avalanche breakdown C. Working voltage
B. Dielectric constant D. Dielectric strength
D. Dielectric strength
89
What refers to the reciprocal dispersion of optical materials?
A. Nusselt number C. Abbe number
B. Prandtl number D. Schmidt number
C. Abbe number
90
The movement of liquid through a phosphor diaphragm of other permeable solid as a result of an applied electric field.
A. Electrophoresis C. Electrical diffusion
B. Electron osmosis D. All of these are correct
B. Electron osmosis
91
Changes of state from where particles are able to move freely to a state where they can no longer move freely and can only vibrate.
A. Melting C. Evaporation
B. Freezing D. Condensation
B. Freezing
92
- Found in compounds that are composed of both metallic and nonmetallic elements
- Bond occurs through transfer of electrons, forming ions.
Ionic bonding
93
- Stable electron configurations are assumed by the sharing of electrons between adjacent atoms
- Bond occurs between two nonmetallic elements
Covalent Bonding
94
The electrostatic interaction between delocalized electrons, called conduction electrons and gathered in an "electron sea", and the metallic nuclei.
Metalic bonding
95
- Interatomic and intermolecular bonds that are relatively
weak and for which bonding energies are relatively small.
- Normally atomic or molecular dipoles are involved.
Van der Waals
96
The energy required to separate two atoms that are chemically bonded to each other.
Bonding / Binding energy
97
Binding energy of covalent
150 - 370
98
Binding energy of ionic
125- 300
99
Binding energy of metallic
25-200
100
Binding energy of van der waals
less than 10
101
In this type of bond, a relatively large interatomic force that tends to energy transfer from one atom to another that are bonded together by coulombic force. It is called the
________ bond.
A. Ionic C. Covalent
B. Metallic D. Secondary
A. Ionic
102
It refers to sharing of delocalized electron to form strong bond between atoms. It is called the ________ bond.
A. Ionic C. Covalent
B. Metallic D. Secondary
B. Metallic
103
It is a type of bond where relatively large interatomic forces are created by the sharing of electrons to form a bond with localized directional atoms. It is called the ________ bond.
A. Ionic C. Covalent
B. Metallic D. Secondary
C. Covalent
104
Ionic bonding was supposed to be believed at first as ________.
A. Sharing of electrons of nonmetallic and nonmetallic atoms
B. Sharing of electrons of metallic and nonmetallic atoms
C. Transfer of electrons of nonmetallic and nonmetallic atoms
D. Transfer of electrons of metallic and nonmetallic atoms
D. Transfer of electrons of metallic and nonmetallic atoms
105
What is the bond angle of water?
A. 109.5 degrees C. 105 degrees
B. 110 degrees D. 107.5 degrees
C. 105 degrees
106
Materials with binding energy in the range of 150 – 370 kcal/mol are considered to exhibit what type of bonding?
A. Ionic C. Covalent
B. Metallic D. Secondary
C. Covalent
107
One in which the atoms are situated in a repeating or periodic array over large atomic distances
Crystalline materials
108
Upon solidification, the atoms will position themselves in a repetitive three-dimensional pattern, in which each atomis bonded to its nearest-neighbor atoms
Crystal Lattice
109
Three – dimensional set of points coinciding with atom positions (or sphere centers)
Lattice
110
The basic structural unit or building block of the crystal structure
Unit cell
111
Materials that does not have a definite crystal structure. Examples are glasses.
Amorphous materials
112
- The characteristic of a material being able to exist in more than one crystal structure, depending on its temperature and pressure.
- Also called polymorphism.
Allotropy
113
A material whose atomic arrangement occurs as periodic, repeating structures over large distances
A. Crystalline C. Polycrystalline
B. Solid D. Amorphous
A. Crystalline
114
An elemental solid having a different crystal structure, usually due to the prevailing temperature and pressure.
A. Crystal C. Polycrystal
B. Allotrope D. Amorphous
B. Allotrope
115
It is the enthalpy change associated with the condensation
of gaseous positive and negative ion into a crystal.
A. Lattice energy C. Enthalpy energy
B. Raoult’s Law D. Schottky defect
A. Lattice energy
116
This refers to a crystal system with two equal axes with one angle equal to 120 degrees
A. Tetragonal C. Orthorhombic
B. Rhombohedral D. Hexagonal
D. Hexagonal
117
This refers to distance between two nuclei of atoms.
A. bond length C. bond distance
B. bond radius D. All of these.
A. bond length
118
The arrangement of the atoms in a material into a regular repeatable pattern.
A. Crystal structure C. Domain
B. Atomic structure D. Lattice
A. Crystal structure
119
This refers to a crystal system with unequal axes with all angles at right angle
A. Tetragonal C. Orthorhombic
B. Rhombohedral D. Hexagonal
C. Orthorhombic
120
The arrangement of the atoms in a material into a regular repeatable pattern
Crystal structure
121
How many crystal are there in the Bravais crystal structure
14
122
There are 14 known crystals structures that exists called the
Bravais crystal structures
123
Composed of atoms on the lattice points of a cube, thus having a total of one atom in each unit cell
Simple cubic
124
Two atoms are associated with each BCC unit cell: the equivalent of one atom from the eight corners, each of which is shared among eight unit cells, and the single center atom.
body centered cubic
125
One-eighth of each of the eight corner atoms and one-half of each of the six face atoms, or a total of four whole atoms, may be assigned to a given unit cell.
Face centered cubic
126
The equivalent of six atoms is contained in each unit cell; one-sixth of each of the 12 top and bottom face corner atoms, one-half of each of the 2 center face atoms, and all 3 midplane interior atoms.
Hexagonal closed pack
127
The number of atoms, that a central atom holds as its nearest neighbors in a crystal
Coordination number
128
The sum of the sphere volumes of all atoms within a unit cell (assuming the atomic hard sphere model) divided by the unit cell volume
Atomic packing factor
129
Atomic packing factor of FCC
0.74
130
Atomic packing factor of HCP
0.74
131
Atomic packing factor of BCC
0.68
132
Coordination no. of FCC
12
133
Coordination no. of HCP
12
134
Coordination no. of BCC
8
135
No. of atoms in FCC
4
136
No. of atoms in BCC
2
137
No. of atoms in HCP
6
138
A shorthand notation to describe certain crystallographic planes in a material.
Miller-indices
139
What is another name for face – centered cubic (fcc) crystal structure?
A. Close Cubic Packed (CCP)
B. Body Centered Cubic (BCC)
C. Hexagonal Close Packed (HCP)
D. Simple Cubic (SC)
A. Close Cubic Packed (CCP)
140
Calculate the volume of an FCC unit cell in terms of the atomic radius R.
A. V = 16R3√4 C. V = 4R3√4
B. V = 16R3√3 D. V = 4R3√3
A. V = 16R3√4
141
What two crystal structures have the same total number of atoms inside?
A. FCC and HCP C. BCC and HCP
B. BCC and CCP D. CCP and FCC
A. FCC and HCP
142
What two crystal structures have the same coordination number?
A. FCC and HCP C. BCC and HCP
B. BCC and CCP D. CCP and FCC
A. FCC and HCP
143
What two crystal structures have the same atomic packing factor?
A. FCC and HCP C. BCC and HCP
B. BCC and CCP D. CCP and FCC
A. FCC and HCP
144
What is the atomic packing factor of simple cubic (SC) crystal structure?
A. 0.68 C. 0.74
B. 0.52 D. 0.93
B. 0.52
145
The element beryllium has what crystal structure?
A. FCC C. HCP
B. BCC D. CCP
C. HCP
146
This refers to the number of atoms touching a particular atom, or the number of nearest neighbors of an atom.
A. Coordination number
B. Miller indices
C. Atomic Packing Factor
D. Bravais Structure
A. Coordination number
147
A lattice irregularity having one or more of its dimensions on the order of an atomic diameter
crystalline defect
148
Where an atom is missing or is in an irregular place in the lattice structure
point defect
149
One normally occupied from which an atom is
missing
Vacancy
150
A self-interstitial is an atom from the crystal that is crowded into an interstitial site, a small void space that under ordinary circumstances is not occupied
point defect
151
-Type of point defect in which an interstitial lies near the vacancy.
- forms when an atom or ion leaves its place in the lattice (leaving a vacancy), and lodges nearby in the crystal (becoming an interstitial)
Frenkel defect
152
A neutral defect of ionic lattices consisting of two vacancies, one cation and one anion
schottky defect
153
A linear or one-dimensional defect around which some of the atoms are misaligned.
dislocation
154
A linear defect that centers around the line that is defined along the end of the extra half-plane of atoms
edge disloction
155
Formed by a shear stress that is applied to produce the distortion
screw dislocation
