Level 1 Theory

Question 1

Iron, Nickel, and Cobalt are what

Answer 1

Materials that magnetic particle inspection can be performed on

Question 2

Reluctance

Answer 2

The opposition that a ferromagnetic material shows to the establishment of a magnetic field

Question 3

What are several advantages over liquid penetrant inspection that Magnetic particle inspection has

Answer 3

Components with thin coatings can be inspected without removing the coating and can be inspected more rapidly

Question 4

A hysteresis loop

Answer 4

Shows the relationship between the Induced magnetic flux density and the magnetizing force

Question 5

Residual magnetism

Answer 5

The magnetic flux density that remains in the material when the magnetizing force is zero

Question 6

Domains

Answer 6

Small polarized regions that make up Ferromagnetic materials

Question 7

What never cross each other

Answer 7

Magnetic lines of force

Question 8

A material with a wider hysteresis loop has

Answer 8

Lower permeability Higher retentivity Higher coercivity

Question 9

What forms closed loops from pole to pole

Answer 9

Magnetic lines of force

Question 10

Direct current

Answer 10

type of current flows continuously in one direction at a constant voltage

Question 11

What is a circular field

Answer 11

A magnetic field induced by a current carrying conductor

Question 12

What is A magnetic pole

Answer 12

A location where a magnetic field can be detected exiting or entering a material

Question 13

What is sometimes restricted to use for potential of arcing that could damage parts

Answer 13

Prods

Question 14

When testing parts with magnetic particles, it is best to magnetize the part how

Answer 14

In two directions at right angles to each other

Question 15

Why are all materials affected in some way by a magnetic field

Answer 15

Because all matter is composed of atoms

Question 16

When does the best detection of defects occur

Answer 16

When the lines of magnetic force are perpendicular to the longest dimension of the defect

Question 17

What is A magnetic field

Answer 17

A volume of space where there is a change in magnetic energy

Question 18

When is a material considered demagnetized

Answer 18

When its residual magnetic field measures less than 3 gauss

Question 19

A material with a Higher permeability has a what

Answer 19

A narrower hysteresis loop

Question 20

Components generally must be demagnetized because residual magnetism can what

Answer 20

Increase wear by attracting abrasive particles, Affect machining and welding processes, or Interfere with near by electronic components

Question 21

Faraday’s Law of Magnetic Induction

Answer 21

The magnetic forces of the material’s electrons will be affected by an external magnetic field

Question 22

High residual magnetism is found in what material

Answer 22

A material with a wider hysteresis loop

Question 23

Magnetically saturated

Answer 23

When all the magnetic domains are aligned

Question 24

Direct induction needs

Answer 24

Good electrical contact must be established between the test equipment and test component

Question 25

When the magnetizing current is stopped, a ferromagnetic material will what

Answer 25

Retain a residual magnetic field withing the component

Question 26

Permeability

Answer 26

Describes the ease with which a magnetic flux is established in a component is called

Question 27

Coercive force

Answer 27

The amount of reverse magnetic field which must be applied to a magnetic material to reduce the magnetic flux to zero

Question 28

It is easier to measure a longitudinal field when

Answer 28

When using both a circular and longitudinal magnetic field

Question 29

When a ferromagnetic material is in a unmagnetized state, the domains are

Answer 29

Randomly organized

Question 30

What establishes a magnetic field that extends from the ID to the OD of a circular part

Answer 30

The circular conductor technique

Question 31

Magnetic flux density

Answer 31

The number of magnetic lines of force cutting thorugh a plane of a given area at a right angle

Question 32

When performing a magnetic particle test with a coil, the part should be placed where

Answer 32

Along the inside edge of the coil

Question 33

Ferromagnetic

Answer 33

Has a large susceptibility to magnetic field

Question 34

A yoke establishes a magnetic field

Answer 34

Between the north and south poles of the yoke

Question 35

A circular magnetic field has lines of force that run where

Answer 35

Circumferentially around the perimeter of the part

Question 36

What happens when a magnetic field cuts across a crack

Answer 36

Magnetic poles form at the edges of the crack

Question 37

Dipole

Answer 37

An object that has a magnetic pole on one end and a second equal but opposite magnetic pole on the other

Question 38

Iron filings

Answer 38

small magnetic particles used in magnetic particle inspection

Question 39

Higher permeability, Lower retentivity, and Lower coercivity are components of what

Answer 39

Narrower hysteresis loop

Question 40

Are dry magnetic particles one color, non-reusable, or one size?

Answer 40

Non-reusable

Question 41

You will find subsurface or surface indications with magnetic particle testing

Answer 41

Subsurface

Question 42

Diamagnetic materials

Answer 42

Have a very weak and negative susceptibility to magnetic field

Question 43

Multidirectional inspection equipment does what

Answer 43

Reduces inspection time

Question 44

A material with Higher reluctance has a what

Answer 44

A wider hysteresis loop

Question 45

Coercive force

Answer 45

The force required to remove the residual magnetism from the material

Question 46

The magnetic field circling each loop of wire in a coil combines with the fields from the other loops to produce a concentrated field

Answer 46

Down the center of the coil

Question 47

A material with Lower coercivity has a what

Answer 47

A narrow hysteresis loop

Question 48

Whats the purpose of heating materials above their curie temperature or reversing and decreasing magnetic field

Answer 48

Demagnetized

Question 49

North Pole

Answer 49

The area where the exit poles are concentrated

Question 50

A longitudinal magnetic field has magnetic lines of force that run

Answer 50

Parallel