6.1 Flashcards
(78 cards)
1
Q
Toughness Definition
A
Resist breaking under impact load
2
Q
Ductility Definition
A
Plastic deformation under tensile strength without fracture
3
Q
Elasticity Definition
A
Return to original shape after deformation
4
Q
Plasticity Definition
A
Retain shape after deformation
5
Q
Malleability Definition
A
Plastic deformation under compressive loads
6
Q
Hardness Definition
A
Ability to withstand scratching or wear
7
Q
Brittleness Definition
A
Tendency to fracture when shock loaded
8
Q
Rigidity Definition
A
Withstand load without failure
9
Q
Hot Shortness Definition
A
Brittle when in High temp
10
Q
Cold Shortness Definition
A
Brittle in low Temp
11
Q
Magnetite %
A
74% iron
12
Q
Haematite %
A
70% iron
13
Q
Carbon content of Pig iron
A
3.5 to 4.5 % carbon
14
Q
To make cast Iron
A
Pig iron remelted with coke and scrap iron in cupola to 1200 °C
15
Q
Ferrite %
A
0.006% carbon
16
Q
Pearlite %
A
0.83% carbon
17
Q
Cementite
A
6.67% carbon
18
Q
SAE digit meanings
A
1st : Principal Alloy Element
2nd : % Principal Alloy Element
3rd and 4th : % carbon in 100ths
19
Q
SAE 1xxx
A
Carbon
20
Q
SAE 2xxx
A
Nickel
21
Q
SAE 3xxx
A
Nickel Chromium
22
Q
SAE 4xxx
A
Molybdenum
23
Q
SAE 5xxx
A
Chromium
24
Q
SAE 6xxx
A
Chromium-Vanadium
25
SAE 7xxx
Tungsten
26
SAE 9xxx
Silicon Manganese
27
Low Carbon Steel %
Below 0.3% carbon
28
Medium Carbon Steel %
0.3 to 0.8% carbon
29
High Carbon Steel %
0.8 to 1.4% carbon
30
Below .83% carbon is
Ferrite + Pearlite
31
At 0.83% carbon is
Pearlite
32
Above 0.83% carbon is
Cementite and Pearlite
33
What degrees approx is lower critical point
723 °C
34
What degrees approx is Upper critical point
850 °C
35
In Low Carbon Steel what happens at LCP and UCP
At 723 °C Austenite and Ferrite
At 850 °C Austenite
36
In High Carbon Steel what happens at LCP and UCP
At 723 °C Austenite and Cementite
At 850 °C Austenite
37
What happens at Eutectoid Point
All Pearlite becomes Austenite
UCP and LCP converge
38
What does Annealing do
Makes steel more malleable and softer
39
What does Normalising do
Removes internal stress
40
What °C does normalising take place
50 °C above UCP
41
What is cooled faster normalising or annealing
Normalising
42
What is Martensite
Hardest structure of plain Steel
Must be above 0.4% carbon
43
What does Tempering do
Reduces Brittleness caused from Hardening
44
Tempering below 200 °C
Removes stresses
45
Tempering above 220 °C
Less hardness higher toughness
Martensite back to pearlite
46
SURFACE HARDENING
Case Hardening
Outside layer carbon content to 0.83%
Happens at 900 to 950 °C
47
SURFACE HARDENING
Box Process / Pack Carburising
Sealed Box
Carbon Rich material
900 °C
Maintained until required
4hrs = 1mm
Cooled slowly to anneal new case
48
SURFACE HARDENING
Heat Treatment
Heated to 850 °C
Quenched
Surfaces not wanting to be hardened protected with copper
49
SURFACE HARDENING
Cyanide Hardening
Put in molten salts at 900 °C
Used for small hardened layers
50
SURFACE HARDENING
Gas Carburising
900 °C
In methane and propane atmosphere
51
SURFACE HARDENING
Flame Hardening
Localised Areas of MID and HIGH carbon steels
Torch heats area
Quenched
Jets on torch cool core
52
SURFACE HARDENING
Induction Hardening
Hardens selected areas of symmetrical components
Heated via Induction Coil
Cooled by water jets
At least 0.4% carbon
53
SURFACE HARDENING
Nitriding
Steels containing Aluminium and Chromium
Box 500 °C
Ammonia gas
Absorbs nitrogen
No quench
54
Formula for stress
Force ÷ CSA
55
Units of Stress
N/mm ² or PSI or MPA
56
Strain Definition
Force applied to a part which resists the force
57
Formula for Strain
Change in Length ÷ OG length
58
Tensile Strength Formula
Max Force Used ÷ OG CSA
59
What measures extension during tensile tests
Extensometers
60
Creep may occur when subjected to
Tensile stress and High temp
61
Fracture of Creep called
Rupture
62
Brinell Test
Steel ball
Diam of indentation using microscope
15seconds
BHN= Force ÷ Area of impression
63
Vickers Test
Diamond pyramid
Diagonal Length of impression
Microscope w/ slit
15 seconds
Vickers > Brinell
64
Rockwell
1/16” Diam of ball or 120°diamond cone
Hardness number on dial
65
Izod
163 J
1side
Drag pointer shows highest energy used to break
66
Charpy
150J or 300J
Both ends
Used at High temp And Low temp
67
Fatigue Definition
Component subjected to Repeated Cyclical loading will eventually fail below UTS
68
Shot Peening
Created Compressive Layer
Uses Steel glass or ceramic balls
Almen strip
69
Ratopeening
Shotpeening for inaccessible areas
Tungsten carbide balls
Flexible flap
Drill held constant
70
Adding Chromium to Steel does?
+ Hardness
+ UTS
+ Corrosion Resistance
~ Ductility
71
Adding Molybdenum to Steel does?
+ Toughness
+ UTS
+ Machine Ability
72
Adding Manganese to Steel does?
+ Toughness
+ UTS
73
Adding Vanadium to Steel does?
+ Hardness
+ Toughness
+ UTS
- Ductility
- Machine Ability
74
What does Tungsten do to Steel
+ Hardness
75
What does Nickel do to Steel
+ Hardness
+ Toughness
+ UTS
+ Ductility
+ Corrosion Resistance
- Machine Ability
76
What is A286
Super Alloy
77
What is A286 comprised of
57% Iron. 2% Titanium
25% Nickel. 0.3% Vanadium
14.5% Chromium. 0.04% Carbon
78
Qualities of A286
High strength
High Temp Resistance
High Corrosion Resistance
