AIRCRAFT STRURAL MATERIALS (METALLIC) Flashcards
1
Q
ABILITY OF A MATYERIAL TO WITHSTAND TENSION
A
TENSILE STRENGTH
2
Q
ABILITY OF A MATERIAL TO RESIST DEFORMATION
A
YIELD STRENGTH
3
Q
ABILITY OF A JOINT TO WITHSTAND ANY FORM OF CRUSHING OR DISTORTION
A
BEARING STREMNGTH
4
Q
ABILITY TO RESIST CUTTING, PENETRATION, OR ABRASION
A
HARDNESS
5
Q
MEATALS ARE HARDENED THROUGH?
A
HEAT-TREATING OR WORK-HARDENING
6
Q
METALS ARE SOFTENED BY A PROCESS CALLED?
A
ANNEALING
7
Q
ABILITY TO BE BENT, FORMED, OR SHAPE WITHOUT BREAKING
A
MALLEABILITY
8
Q
TENDENCY OF A MATERIAL TO BREAK
A
BRITTLENESS
9
Q
Enables a metal to carry heat or electricity.
A
CONDUCTIVITY
10
Q
Property of a metal to expand when heated and shrink when cooled. The amount of expansion or contraction is predictable at specific temperatures
A
THERMAL EXPSION
11
Q
Metal’s tendency to return to its original shape after normal stretching and bending.
A
ELASTICITY
12
Q
Point beyond which the metal does not return to its original shape after a deforming force is removed.
A
ELASTIC LIMIT
13
Q
Metal’s ability to resist tearing or breaking when it is bent or stretched.
A
TOUGHNESS
14
Q
Formed by physically working the metal into shape.
A
WROUGHT OBJECTS
14
Q
Ability of metal to be joined by heating and melting.
A
FUSIBILITY
15
Q
Material’s mass per unit volume.
A
DENSITY
16
Q
Formed by pouring molten metal into molds.
A
CAST OBJECTS
17
Q
Process of forming metal at an elevated temperature when it is in its annealed, or soft condition.
A
HOT WORKING
18
Q
consists of forming hot metal ingots with rollers to form sheets, bars, and beams.
A
ROLLING
19
Q
worked at temperatures above its critical range.
A
FORGING
20
Q
Used to form large and heavy parts.
A
PRESSING
21
Q
Hammering process whereby a hot ingot is placed between a pair of formed dies in a machine called a drop hammer and a weight of several tons is dropped on the upper die.
A
DROP FORGING
22
Q
Type of forging that is usually used on small parts because it requires a metalworker to physically hammer a piece of metal into its finished shape.
A
HAMMERING
23
Q
Performed well below a metal’s critical temperature.
Strain hardens the worked metal, increasing its strength and hardness but decreasing ductility.
A
COLD-WORKING
24
Used in making seamless tubing, wire, streamlined tie rods, and other forms of stock.
cold drawing
24
rolling of metal at room temperature to its approximate size.
COLD ROLLING
25
Process of forging metal through a die which imparts a required cross-section to the metal.
extrusion
26
Metals which have elements other than iron as their base.
NON-FERROUS METALS
27
1XXX
Offers high corrosion resistance, excellent thermal and electric properties but very low in strength.
ALUMINUM
28
2XXX
Metallic changes take place in the resultant alloy’s grain structure. However, it is susceptible to intergranular corrosion when improperly heat-treated.
COPPER
29
3XXX
Non heat treatable. Offers moderate strength and has good working characteristics.
MANGANESE
30
4XXX
Lowers a metal’s melting temperature. This results in an alloy that works well for welding and brazing.
SILICON
31
5XXX
Good welding and corrosion-resistance characteristics. However, if the metal is exposed to high temperatures or excessive cold working, its susceptibility to corrosion increases.
MAGNESIUM
32
6XXX
Medium strength with good forming and corrosion-resistance properties.
MAGNESIUM AND SILICON
33
7XXX
Used when parts require more strength and little forming. This alloy is very hard and is difficult to bend.
ZINC
34
8XXX
OTHER ELEMENTS
35
represents a specific alloy modification.
SECOND NUMBER
36
Pure aluminum coating that is rolled on to the surface of heat-treated aluminum alloy.
The thickness of this coating is approximately 5% of the alloy’s thickness on each side.
CLAD ALUMINUM ALLOY
37
Series of operations involving the heating and cooling of metals in their solid state.
HEAT TREATMENT
38
Process of heating certain aluminum alloys to allow the alloying element to mix with the base metal. Metal is heated in either a molten sodium or potassium nitrate bath or in a hot-air furnace to a temperature just below its melting point.
SOLUTION HEAT TREATMENT
39
Heat-treatable aluminum alloys are comparatively soft when first removed from a quench.
PRECIPITATION HEAT TREATMENT
40
When alloy is allowed to cool at room temperature, it is referred to as
NATURAL AGING
41
Process that softens a metal and decrease internal stress.
ANNEALING
42
T
SOLUTION HEAT TREATED
43
T2
ANNEALED(CAST)
44
T3
SHT STRAIN HARDENED
45
T4
SHT NATURALLY AGED
46
T5
ARTIFICIALLY AFED
47
T6
SHT ARTIFICIALLY AGED
48
T7
SHT STABILIZED
49
T8
SHT
STRAIN HARDENED, ARTIFICIALLY AGED
50
T9
SHT,
ARTIFICIALLY AGED, STRAIN HARDENED
51
T10
ARTIFICIALLY AGED, STRAIN HARDENED
52
Material which has been previously heat-treated can generally be reheat treated any number of times. As an example, rivets made of 2017 or 2024 are extremely hard and typically receive several reheat treatments to make them soft enough to drive.
REHEAT TREATMENT
53
Both heat-treatable and nonheat-treatable aluminum alloys can be strengthened and hardened through strain hardening, also referred to as cold working or work hardening. The mechanical working can consist of rolling, drawing, or pressing.
STRAIN HARDENING
54
F
FABRICATED
55
O
ANNEALED
56
H
STRAIN HARDENED
57
H1
STRAIN HARDENED ONLY
58
H2
SH, PARTIALLY ANNEALED
59
H3
SH, STABILIZED
60
H4
sh and baked
61
HX2
QUARTERED HARD
62
HX4
HALF HARD
63
HX6
THREE-QUARTERED HARD
64
HX8
FULL HARD
65
HX9
EXTRA HARD
66
Used for castings and in its wrought form is available in sheets, bars, tubing, and extrusions.
MAGNESIUM AND ALLOYS
67
Light weight metals with very high strength. They also have excellent corrosion resistance characteristics. However, since the metal is sensitive to both nitrogen and oxygen, it must be converted to titanium dioxide with chlorine gas.
TITANIUM AND ALLOYS
68
Medium strengths of 120 KSI to 150 KSI, can be welded and used in forgings.
ALPHA
69
Medium strength in the annealed condition and much greater strength when heat treated. Not weldable.
ALPHA-BETA
70
Medium strength, excellent forming characteristics. Can be heat-treated to a very high strength.
BETA
71
68% nickel, 29% copper
MONEL
72
80% nickel, 14% chromium
INCONEL
73
COPPER+ZINC
BRASS
74
COPPER+TIN
BRONZE
75
97% copper, 2% beryllium
BERRYLIUM COPPER
76
Any alloy containing iron as its chief constituent.
FERROUS METALS
77
Fairly soft, malleable, and ductile.
IRON
78
Pig iron is re-melted in a special furnace.
STEEL
79
SAE-1XXX
When mixed with iron, compounds of iron carbides called cementite form.
CARBON
80
SAE-2XXX
Adds strength and hardness to steel and increases its yield strength. Used in producing aircraft hardware such as bolts, nuts, rod ends, and pins.
NICKEL
81
SAE-3XXX
Nickel toughens steel, and chromium hardens it. Used for forged and machined parts requiring high strength, ductility, shock resistance, and toughness.
NICKEL CHROMIUM
82
SAE-4XXX
Reduces the grain size of steel and increases both its impact strength and elastic limit. Extremely wear resistant and possess a great deal of fatigue strength.
MOLYBDENUM
83
SAE-5XXX
Increase strength and hardness as well as improve its wear and corrosion resistance. Used in balls and rollers of antifriction bearings.
CHROMIUM
84
SAE-6XXX
CHROMIUM VANADIUM
85
SAE-7XXX
Extremely high melting point, typically used for breaker contacts in magnetos and for high-speed cutting tools.
TUNGSTEN
86
SAE-8XXX
NICKEL CHROMIUM VANADIUM
87
SAE-9XXX
SILICON AND MANGANESE
88
0.10-0.30 - Easily welded and machines readily, does not accept heat treatment.
LOW
89
0.30-0.50 - Accept heat treatment, adaptable for machining or forging
MEDIUM
90
0.50 - 1.05 - Used in springs, files, and some cutting fools
HIGH
91
Causes steel to be brittle when rolled or forged and must be removed in the refining process.
SULFUR
92
Acts as a hardener. It also improves ductility.
SILICON
93
Raises the yield strength of steel. However, no more than 0.05% ____
PHOSPHOROUS
94
toughness and wear resistance make it a good material for engine cylinders and other highly stressed engine parts.
CHROME-MOLYBDENUM
95
Corrosion resistance steels that contain large amount of chromium and nickel. Suited for high temperature applications such as firewalls and exhaust system components.
STAINLESS STEEL
96
When these steels are heated to a temperature above their critical range, a structure known as austenite forms. Austenite is a solid solution of pearlite. Hardened only by coldworking while heat treatment serves only to anneal them.
AUSTENTIC
97
No carbon and do not respond to heat treatment.
FERRITIC
98
Extremely hard if allowed to cool rapidly by quenching from an elevated temperature. They are magnetic.
MARTENSITIC
99
Increase both ultimate tensile strength and toughness. Most wrenches and ball bearings are made of chromium-vanadium steel.
VANADIUM
100
Alpha solid solution of iron containing some carbon and exists at temperatures below the lower critical temperature.
FERRITE
101
Above the lower critical temperature, the steel begins to turn into austenite, which consists of gamma iron containing carbon.
AUSTENTITE
102
Softens steel and relieves internal stress. It is heated to about 50F above its critical temperature, soaked for a specified time, then cooled. Soaking time is typically around one hour per inch of material thickness.
ANNEALING
103
The processes of forging, welding, or machining usually leave stresses within steel that could lead to failure. These stresses are relieved in ferrous metals. Heated to about 100F above its upper critical temperature and held there until the metal is uniformly heat soaked. The steel is in then removed from the furnace and allowed to cool in still air.
NORMALIZING
104
It is heated above its critical temperature so carbon can disperse uniformly in the iron matrix. Once this occurs, the alloy is cooled rapidly by quenching it in water, oil, or brine.
HARDENING
105
provides the slowest quench
OIL
106
provides the MOST RAPID quench
BRINE
107
Reduces the undesirable qualities of martensitic steel. It is heated to a level considerably below its critical temperature. It is then allowed to cool to room temperature in still air.
TEMPERING
108
Certain components in aircraft engines and landing gear systems require metal with hard, durable bearing surfaces and core material that remains tough accomplished through
CASE HARDENING
109
Forms a thin layer of high-carbon steels on the exterior of low-carbon steel.
CARBURIZING
110
Enclosing the metal in a fire-clay container and packing it with a carbon-rich material such as charcoal.
PACK
111
Carbon monoxide gas combines with gamma iron and forms a high-carbon surface.
GAS
112
Produces a high-carbon surface when a part is heated in a molten bath of sodium cyanide or barium cyanide.
LIQUID
113
Uses a hydraulic force to impress a spherical penetrator into the surface of a sample. The amount of force used is approximately 3,000 kg for steel, and 500 kg for nonferrous metals.
BRINELL HARDNESS TEST
114
First hardened, tempered, and then ground to its finished dimensions before it is case hardened. Heated to a temperature of approximately 1000F, and then surrounded by ammonia gas (NH3).
Engine crankshafts and cylinder walls are commonly nitrided for increased wear resistance.
NITRIDING
115
Measures the depth to which the penetrator sinks into the material. Uses a conical diamond, a 1/16 inch ball, and a ⅛ inch ball. There are also three major loads: 60 kg, 100 kg, and 150 kg.
ROCKWELL HARDNESS TEST
116
Formed from ingots of aluminum alloy that are passed through a series of rollers until the metal is reduced to a desired thickness.
SHEET METAL GRAIN
117
A radius is measured on the inside of a bend and is generally measured in fractions.
To prevent cracks, a minimum _________ is recommended for different types of alloys and metal thickness
BEND RADIUS
118
When bending a piece of metal around a radius, the metal on the outside of the bend stretches, while the metal toward the inside tends to compress or shrink. The line along which this occurs is called the
NEUTRAL AXIS
119
Used to designate the dimensions of a piece of metal on a drawing or layout pattern.
MOLD LINE
120
Point where two mold lines intersect in a bend.
MOLD POINT
121
Designate the location where the sheet metal begins to form around the bend radius.
BENT TANGENT LINE
122
Distance between the mold line and the bend tangent line inside the bend area.
SETBACK
123
When a sheet metal structure is built up, there are often locations where the metal is stacked into multiple layers where the parts are joined together. In order for the sheet metal pieces to be flat against the skin and yet have one on top of the other at the joining intersection.
JOGGLING
124
Allowable damage covered in the SRM
COSMETIC
125
Repairable damage covered in the SRM
Specific damage requires manufacturers approval
STRUCTURAL
