Test 2

Question 1

plain carbon steel

Answer 1

10xx

Question 2

resulfurized carbon steel

Answer 2

11xx

Question 3

chromium 0.5-0.95%

molybdenum 0.12-0.2%

Answer 3

41xx

Question 4

nickel 1.8%
chromium 0.5-0.8%
molybdenum 0.25%

Answer 4

43xx

Question 5

chromium 1.45%

Answer 5

52xx

Question 6

aids nitriding
restricts grain growth
removes oxygen in steel melting

Answer 6

Aluminum (Al) < 2%

Question 7

adds machinability

reduces weldability, ductility and toughness

Answer 7

Sulfur (S) and Phosphorus (P) <0.5%

Question 8

increases resistance to corrosion and oxidation
increases hardenability (significant effect)
increases high-temperature strength
can combine with carbon to form hard, wear-resistant microconstituents

Answer 8

Chromium (Cr) 0.3-0.4%

Question 9

promotes austentic structure
increases hardenability (mild effect)
increases toughness

Answer 9

Nickel (Ni) 0.3-5%

Question 10

promotes tenacious oxide film to aid atmospheric corrosion resistance

Answer 10

Copper (Cu) 0.2-0.5%

Question 11

increases hardenability, lowers hardening temperature
promotes an austentic structure
combines with sulfur to reduce its adverse affects

Answer 11

Manganese (Mn) 0.3-2%

Question 12

removes oxygen in steelmaking
improves toughness
increases hardenability
improves the fluidity of molten metal

Answer 12

Silicon (Si) 0.2-2.5%

Question 13

promotes grain refinement
increases hardenability
improves high-temperature strength

Answer 13

Molybdenum (Mo) 0.1-0.5%

Question 14

promotes grain refinement
increases hardenability
will combine with carbon to form wear-resistant microconstituents

Answer 14

Vanadium (V) 0.1-0.3%

Question 15

added in small amounts to increases hardenability

Answer 15

Boron (B) 0.0005-0.003%

Question 16

added only to aid machinability

Answer 16

Lead (Pb) <0.3%

Question 17

acts like carbon in strengthening

Answer 17

Nitrogen (N) <0.1%

Question 18

cold work water hardening

Answer 18

W

Question 19

cold work oil hardening

Answer 19

O

Question 20

cold work medium alloy air hardening

Answer 20

A

Question 21

cold work high C, high Cr

Answer 21

D

Question 22

shock resisting

Answer 22

S

Question 23

hot work

Answer 23

H

Question 24

high speed molybdenum

Answer 24

M

Question 25

high speed tungsten

Answer 25

T

Question 26

mold

Answer 26

P

Question 27

special purpose

Answer 27

L

Question 28

99% pure or higher
used in electrical and chemical fields
excellent corrosion resistance
high thermal and electrical conductivity
low mechanical properties and excellent workability
moderate increases in strength from strain hardening
iron and silicon major impurities

Answer 28

1000 series

non heat treatable

Question 29

copper – principal alloying element
may require artificial aging
do not have as food corrosion resistance as most other Al alloys
often clad with 6000 series or pure Al

Answer 29

2000 series (2024 best known alloy)
heat treatable - require solution heat treatment to obtain best properties 
in heat treated condition, mechanical properties close to or even exceed mild steel

Question 30

manganese – major alloying element
limited Mn addition - 1.5%
moderate strength
good workability

Answer 30

3000 series (3003 – general purpose alloy)
non heat treatable

Question 31

silicon – major allowing element
Si lowers melting point without causing brittleness
Used in welding wire and brazing alloys
When diluted with heat treatable alloys in welding become moderately heat treatable
Become dark gray when anodized

Answer 31

4000 series

Non heat treatable

Question 32

Magnesium – major alloying element
Mg most effective and widely used alloy for Al
Moderate to high strength
Mg more effective than Mn as hardener (0.8% Mg ≈ 1.5% Mn)
Mg has greater solubility in Al than does Mn
Good welding characteristics
Good resistance to marine atmospheric corrosion
May have problems with stress corrosion cracking at higher service temperatures, higher cold work higher Mg content

Answer 32

5000 series

Non heat treatable

Question 33

Silicon and Magnesium – major alloying elements 
Forms magnesium silicide 
Less strong than 2000 or 7000 series 
Good formability 
Good corrosion resistance 
Medium strength

Answer 33

6000 series (6061 – most widely used and versatile Al alloy)
heat treatable

Question 34

Zinc – major alloying element
High strength
Used for highly stressed parts and aircraft applications
Not arc welded well – resistance welded

Answer 34

7000 series

heat treatable