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Flashcards in Metallurgy Deck (115)
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1
Q

The science that explains the properties, behavior, and internal structure of metals is called what?

A

Metallurgy

2
Q

Electrical and thermal conductivity, hardness, strength, ductility and toughness are all:

A

Metallurgical properties

3
Q

The ability to withstand impact is:

A

Toughness

4
Q

Fracture toughness results will often be expressed in terms of:

A

Breaking energy

5
Q

As hardness is increased, _______ is decreased.

A

Ductility

6
Q

As temperature increases during tempering, what property decreases?

A

Hardness

7
Q

Rockwell, Vickers, Knoop and Brinell are tests used to determine what metallurgical property?

A

Hardness

8
Q

The ability to deform without failing is:

A

Ductility

9
Q

As temperature decreases, which property also decreases?

A

Ductility

10
Q

Aluminum, copper and soft steels are high in what metallurgical property?

A

Ductility

11
Q

Ductility can be expressed in terms of:

A

Percent elongation and/or reduction of area

12
Q

The absence of ductility cannot be measured itself, but the metallurgical property is called:

A

Brittleness

13
Q

The tendency to deform very little before failing suddenly describes:

A

Brittleness

14
Q

As a materials hardness increases, does its strength increase?

A

Yes

15
Q

The ability to resist crushing is:

A

Compressive strength

16
Q

The ability to withstand indentation is:

A

Hardness

17
Q

Files and drill bits are high in what metallurgical property?

A

Hardness

18
Q

Impact wrenches, jack hammers and connecting rods are high in what matellurgical property?

A

Toughness

19
Q

Lifting tools, come-a-longs and bearing pullers are high in what metallurgical property?

A

Tensile strength

20
Q

The ability to withstand a static load is:

A

Strength

21
Q

The ability of a material to return to its original form after stress is removed is called:

A

Elasticity

22
Q

The ability of a material to be cyclically loaded without failing is called:

A

Fatigue strength

23
Q

Deformation caused by stress is called what?

A

Strain

24
Q

A material performs elastically until it passes its yield point. After its yield point has been reached, the material performs:

A

Plastically

25
Q

The property expressed in terms of endurance limit is:

A

Fatigue strength

26
Q

The point on a stress-strain curve where the material changes from elastic to plastic is called its:

A

Yield point

27
Q

When atoms or molecules group together in a neat, orderly formation, they form what?

A

Grains (crystals)

28
Q

Larger or smaller, which grain size exhibits greater strength?

A

Smaller

29
Q

Are course grains weaker than small grains?

A

Yes

30
Q

What is the lower transformation temperature of steel?

A

1,333 F

31
Q

A graph showing the phases and temperatures at which alloys exist is called what?

A

Phase diagram

32
Q

What does PWHT stand for?

A

Post Weld Heat Treatment

33
Q

Which type of PWHT (post weld heat treatment) results in the softest carbon steel?

A

Annealing

34
Q

The type of PWHT (post weld heat treatment) where the material is heated above the lower transformation temperature, held for a certain amount of time, and slow cooled in a furnace is:

A

Annealing

35
Q

Which type of PWHT (post weld heat treatment) softens the metal more than normalizing?

A

Annealing

36
Q

The type of PWHT (post weld heat treatment) where the material is heated above the lower transformation temperature, held for a certain amount of time, and cooled in still air is:

A

Normalizing

37
Q

The type of PWHT (post weld heat treatment) where the material is heated to less than the lower transformation temperature and slow cooled:

A

Stress relieving

38
Q

Which types of PHWT (post weld heat treatment) involve heating the metal to a temperature between 1500 - 1800 F?

A

Normalizing and annealing

39
Q

The PWHT (post weld heat treatment) that follows quenching and restores some of the metal’s ductility is:

A

Tempering

40
Q

Brine, water or oil may be used for what PWHT (post weld heat treatment) technique?

A

Quenching

41
Q

The primary goal of PWHT (post weld heat treatment) is to relieve what?

A

Residual stress

42
Q

What technique for controlling distortion does not help reduce residual stress?

A

External restraint

43
Q

What two factors determine if a material requires preheat?

A

Carbon equivalent and thickness

44
Q

Use of preheat results in:

A

A slower cooling rate and wider HAZ (heat affected zone)

45
Q

The capacity of a material to be welded into a specific, suitably designed structure performing satisfactorily in the intended service is called:

A

Weldability

46
Q

Carbon equivalent is used to determine which property?

A

Weldability

47
Q

Low-carbon steel has a carbon content of _____ % or less.

A

0.30%

48
Q

Medium-carbon steels have a carbon content between 0.30% and ______%.

A

0.55%

49
Q

A pure substance composed of a single material is called what?

A

An element

50
Q

Steels that are primarily made of iron are called:

A

Ferrous

51
Q

A material made up of two or more elements, at least one of which is a metal, is called what?

A

An alloy

52
Q

Which alloying element has the greatest effect on steel?

A

Carbon

53
Q

Which alloying element gives carbon steel the best corrosion resistance?

A

Chrome

54
Q

What two ways can atoms of an alloy be incorporated into the original metal structure?

A

Substitutionally or interstitially

55
Q

The type of alloying where atoms of the alloy take the places of original atoms in a metals structure is known as:

A

Substitutional alloying

56
Q

The type of alloying where atoms of the alloy are dispersed between the original structure is known as:

A

Interstitial alloying

57
Q

Steels alloyed with carbon and only a low percentage of silicon and manganese are known as:

A

Plain carbon steels

58
Q

The melting point of steel is approximately:

A

2,500 F

59
Q

Time-temperature-transformation (TTT) charts show what?

A

Grain growth

60
Q

Carburizing, nitriding and localized heating are types of what?

A

Surface hardening

61
Q

The surface-hardening technique that impregnates the outer surface of steel with carbon is called:

A

Carburizing

62
Q

In the four digit numbering system for steels, what do the last two numbers designate?

A

Percentage of carbon

63
Q

In the four digit numbering system for steels, what do the first two numbers designate?

A

Major alloying elements

64
Q

For a steel designated 4140, what is its carbon content?

A

0.40%

65
Q

The process of removing dissolved oxygen from molten metal is called:

A

Deoxidation

66
Q

The energy applied to the work-piece during welding is called:

A

Heat input

67
Q

The calculation for heat input is:

A

(Amps x Volts x 60) / Travel Speed = J/in

68
Q

Using a smaller diameter electrode and increasing travel speed will have what effect on heat input?

A

Heat input will decrease

69
Q

An increase in amperage and voltage will have what effect on heat input?

A

Heat input will increase

70
Q

The unit for measuring work or heat energy is called a:

A

Joule

71
Q

Expansion and shrinkage during welding causes what two stresses?

A

Residual stress and distortion

72
Q

Relieving residual stress in a weld by using impact blows is called:

A

Peening

73
Q

Can stress relieving be accomplished by mechanical means?

A

Yes

74
Q

Vibratory stress relief is another term for what mechanical stress relief?

A

Peening

75
Q

The portion of base metal which has not been melted, but whose mechanical properties or microstructure has been altered by the heat of welding is called:

A

Heat-affected zone (HAZ)

76
Q

HAZ stands for:

A

Heat affected zone

77
Q

All matter contains heat down to absolute zero. What temperature is absolute zero?

A

-460 F

78
Q

Protons, neutrons and electrons form what?

A

Atoms

79
Q

What is the smallest part of an element?

A

An atom

80
Q

Atoms changing position while a material is in its solid state is called:

A

Diffusion

81
Q

Atoms combine to form what?

A

Molecules

82
Q

Carbon steel exists in what unit cell arrangement at room temperature?

A

BCC

body centered cubic

83
Q

Which microstructure is the hardest?

A

Martensite

84
Q

The unit cell arrangement with the closest arrangement of atoms is:

A

HCP

hexagonal closed packed

85
Q

The three types of unit cell arrangement for metals are:

A

BCC, FCC, and HCP

body centered cubic, face centered cubic, and hexagonal closed packed

86
Q

Which crystal lattice structure is shown here?

A

BCC

body centered cubic

87
Q

Which crystal lattice structure is shown here?

A

FCC

face centered cubic

88
Q

Which crystal lattice structure is shown here?

A

HCP

hexagonal close packed

89
Q

Which microstructure is shown here, characterized by a fine, needle-like apprearance?

A

Martensite

90
Q

Rapid cooling of carbon steel from the austenitic range will result in the formation of:

A

Martensite

91
Q

Slow cooling of steel helps produce a soft, ductile microstructure which has a lamellar appearance when viewed under a microscope. This structure is:

A

Pearlite

92
Q

Which microstructure is shown here, characterized by a lamellar appearance?

A

Pearlite

93
Q

Which microstructure is shown here, the result of combining two other microstructures?

A

Ferrite-pearlite

94
Q

Which microstructure is shown here, characterized by being mostly white with only small carbon deposits in black.

A

Ferrite

95
Q

The maximum temperature that a metal reaches during welding is called:

A

Interpass temperature

96
Q

Organic compounds like water, oil and grease all contain what element that can be detrimental to welding?

A

Hydrogen

97
Q

Which alloying element acts as a deoxidizer?

A

Silicon

98
Q

Which alloying element improves corrosion resistance?

A

Chrome

99
Q

Which alloying element increases toughness and ductility?

A

Nickel

100
Q

The three states of matter are:

A

Liquid, solid and gas

101
Q

A wider HAZ (heat affected zone), a slower cooling rate and smaller grain size are all benefits of what?

A

Preheat

102
Q

Metals like aluminum, brass and copper that do not have iron as their base are called what?

A

Non-ferrous

103
Q

A steel designated 4130 has a carbon content of what?

A

0.30%

104
Q

Quenching a material from temperatures above the lower transformation temperature will result in what microstructure?

A

Martensite

105
Q

What crystal lattice structure can be described as a cube with an atom at each corner and a single atom in the center of the cube?

A

BCC

body centered cubic

106
Q

What lattice structure can be described as a cube with an atom at each corner and an atom in the center of each face of the cube?

A

FCC

face centered cubic

107
Q

Does molten steel have a crystal lattice structure?

A

No

108
Q

What happens to matter as it is heated?

A

It expands

109
Q

Stainless steels have a minimum chromium content of:

A

12%

110
Q

Ferritic, martensitic, austenitic and precipitation hardened are all types of:

A

Stainless steels

111
Q

“300” series stainless steels is what grade?

A

Austenitic

112
Q

“400” series stainless steels are what grade?

A

Martensitic

113
Q

Which state of matter has the least amount of energy?

A

Solid

114
Q

The ability of a material to absorb energy is:

A

Toughness

115
Q

Metals that are strongly attracted by a magnet are called what?

A

Ferromagnetic