問題一覧
1
Metals which contain iron is
ferrous metals
2
The carbon content in medium carbon steel is
0.3-0.8 %.
3
A steel with 1.3 % carbon content is
a high carbon steel
4
Pearlite is a laminate microstructure of steel consisting of
ferrite and cementite
5
Cementite is
Strong but hard and brittle
6
Grinding of a steel reveals a dull but spark pattern (lots of forking)
It is likely to be high carbon steel
7
Plasticity
is the opposite to elasticity
8
Toughness is the opposite of
brittleness
9
is the ability to resist off-set (scissor action) loads
Shear strength
10
An Impact Test measures
toughness
11
The Charpy and Izod tests are types of
impact tests
12
The brinell hardness testers uses
a steel ball indenter
13
the effects of annealing steel
decrease in internal stress ,softening of the metal
14
Steel annealing process it
relieves internal stress suffered after engineering processes
15
Fatigue tests can be carried out
either on individual components or on complete aircraft structure
16
Case hardening is
heat-treating process of metal produces a hard, wear-resistant surface over a strong, tough core
17
Thermal conductivity
ability of a material to conduct a certain amount of heat within a given time, copper is a good example.
18
Nitriding of steel by
ammonia gas
19
the aluminum will have
a lower VPN than the steel
20
The Bayer process to convert
bauxite to alumina
21
Duralumin
2000 series of aluminum alloy
22
Primary aircraft structure (skin and spars etc.)
made of C-110M titanium
23
The ‘Nimonic’ series of alloys are
high temperature , corrosion resistance alloys
24
The melting point of titanium is
1668˚C
25
The two classes of aluminum alloy is done to
Wrought (worked) and Cast
26
The mechanical properties of pure aluminium are
silvery white metal which is soft and ductile
27
Adding other elements to aluminum alloys , such as copper ,manganese or magnesium
decrease corrosion resistance of the aluminum
28
Clad aluminum alloy (alclad)
5% of alloy thickness
29
The heat treatment of clad aluminum alloys must not be carried out more than
three (3) times
30
The purpose of rivets Refrigeration
to make rivets
31
The identification No. of zinc in aluminum alloy is
7
32
The 6000 series of aluminum alloy principle alloying element of
magnesium and silicon
33
For aluminum alloy, the maximum time between removal from heat treatment furnace and quenching must be not more than
7 Seconds
34
A salt bath is a heated tank containing mineral salts , typically
90% nitrate and 10% sodium nitrate
35
Aluminium Solution heat treating is
the process of heating aluminium at prescribed temperature for a prescribed time and then cooling rapidly usually by quenching in water
36
Precipitation heat treatment of aluminum alloy is done to
speed up age hardening process
37
In aircraft engineering terms, a composite usually consists of
a plastic resin matrix and reinforcing fibres of various materials
38
Epoxy resins
are the most widely used resin types for aerospace adhesive and composite applications
39
Epoxy resins advantage that they
do not react with the solvents and dopes used for fabric coverings
40
Cyanate esters
the material’s has dielectric properties for manufacturing
41
The composite part must be as strong and durable as
the original
42
the fibres in composite can be wound tightly to increase
strength
43
Non-heat treatable aluminum alloys can be hardened by
strain hardening
44
In (5052-H24) the letter H indicates
Strain hardening
45
The composite structural defect of separation of composite panel plies is called
delamination
46
Common method of non-destructive of composite material are:
●Tap test ●Ultrasonic inspection ●Radiography/ X ray ●Vibration method and ●Thermal imaging
47
Specific repair instruction and limitations of damage of composite are provided in
Structural Repair Manual
48
proposed repair scheme should meet all the original design requirements
for the structure
49
Adhesive joints are liable to experience main types of stress:
●Tensile ●Shear ●Cleavage and ●Peel
50
Strength
is the name of the ability to support load without breaking
51
Impact resistance
is the ability of a material to withstand impact without shattering
52
Stiffness
is the ability of a material to support a load without bending too much
53
The name given to the longitudinal direction of the fiber in woven fabric is
warp
54
‘A’ Glass
is a standard soda glass in common use for windows , etc
55
‘C’ Glass
is high resistance to corrosive materials. It is normally produced and used only as a surface matt
56
A fibre made
of glass
57
Aramid fibres
do not resist flame well and burn through more quickly than other fibres
58
Carbon fibres
are made from pure carbon and are black in colour
59
Ceramic fibres are used in heat resistant blankets and to weave fireproof cloth for engine and pylon protection
high temperature application is required ,e.g. a firewall
60
Polyesters are two or three-part systems have good environmental resistance and heat resistance up
to150˚C
61
Polyester fabric, used on a fabric covered airplane may be attached to the structure by
strings or by use of fabric adhesives
62
A laminate
is a simple structure built-up from layers of cloth impregnated with resin
63
Plastics are made from materials obtained from
animal or vegetable products and coal or petroleum by-products
64
Most aircraft control system pulleys are made from
Tufnol
65
The best type of wood to be used in the construction of aircraft is
Sitka Spruce
66
The standard wood type for aircraft wood structures is
Spruce
67
When selecting wood suitable for aircraft structural use , the growth
rate should be more than 6 rings per inch(25 mm)
68
The usual method of repairing elongated bolts in a wooden structure is done by
fitting steel bushes
69
Heart shake defect of wood is indicated by a parting of the
annular rings
70
On a wooden aircraft structure if there is no evidence of fiber adhesion in the glue in a failed glued joint
this may indicate glue deterioration
71
Curved wooden parts are made by
soaking or steaming wood strips
72
Fish – eyes are small areas which have not dried uniformly due to
surface contamination with oil, wax or silicone products
73
Iron oxide is sometimes added to aircraft dope to improve it's
durability to adhesion
74
Fabric repair seams on a fabric covered aeroplane should be
covered with tape
75
Lacing cord or stringing chord used on aircraft fabric covering must have a minimum breaking strength of
60 Ib
76
Retarder is used to slow the drying time of dope finishes to prevent
blush
77
Observation
is the only inspection method for identifying excess tension in aircraft fabric covering
78
Excessive tension in aircraft fabric is
usually caused by excessive dope film on new covering
79
Chemical oxidation is the
direct combination of a metal with the oxygen in the atmosphere
80
Oxidation rate of a metal usually
increase with an increase in temperature
81
In the galvanic action process
the anode always corrodes
82
In the process of crevice corrosion, the anodic are is at
the bottom of the crevice
83
When a metal is in contact with a fluid which promotes the growth of microbiological contaminants , such as in kerosene fuel and toilet waste fluids
microbiological corrosion is a present danger
84
Intergranular corrosion is caused by
incorrect heat treatment
85
Magnesium alloys
are not susceptible to intergranular corrosion
86
Hormocoins resinae
is a microbial fungal growth in kerosene fuel
87
Intergranular corrosion
often cannot be detected and has no visual surface indication
88
Mercury contamination
can be recognized on aluminum alloys by the appearance of grayish powder fuzzy
89
The oxide film formed on the surface of aluminium is
non-porous
90
Corrosion will spread more rapidly when metals are exposed to
high temperatures
91
Corrosion at the grain boundaries is called
intergranular
92
Intergranular corrosion
attack along the grain boundaries, or immediately adjacent to grain boundaries
93
can be confirmed by
X-ray inspection
94
Stress corrosion is
corrosion due to fretting
95
Galvanic corrosion
is another name for electrolytic, electro‑chemical or dissimilar metal corrosion
96
Pitting corrosionis a form of extremely localized corrosion that leads to the creation of small holes in the metal may be caused by
localized damage to protective coating