MMET 207 Exam Questions With 100% Verified
Answers!!
Aluminum (Al)
<2 alloy percentage; Aids nitriding, restricts grain growth, removes oxygen in steel melting
Sulfur and phosphorous (S,P)
<0.5 alloy percentage ; Adds machinability, reduces weldability, ductility, and toughness
Chromium (Cr)
0.3-4 alloy percentage; Increases resistance to corrosion and oxidation, increases hardenability,
increases high temperature strength, can combine with carbon to form hard, wear resistant
microconstituents
Nickel (Ni)
0.3-5 alloy percentage; promotes austenitic structure, increases hardenability, increases
toughness
Copper (Cu)
0.2-0.5 alloy percentage; promotes tenacious oxide film to aid atmospheric corrosion resistance
Manganese (Mn)
0.3-2 alloy percentage; increases hardenability, lowers hardening temperature, promotes an
austenitic structure, combines with sulfur to reduce its adverse effects
Silicon (Si)
0.2-2.5 alloy percentage; removes oxygen in steelmaking, improves toughness, increases
hardenability
Molybdenum (Mo)
, 0.1-0.5 alloy percentage ; promotes grain refinement, increases hardenability, improves high
temperature strength
Vanadium (V)
0.1-0.3 alloy percentage; promotes grain refinement, increases hardenability, will combine with
carbon to form wear resistant microconstituents
Boron (B)
0.0005-0.003 alloy percentage; added in small amounts to increase hardenability
Lead (Pb)
<0.3 alloy percentage; added only to aid machinability
Nitrogen (N)
<0.1 alloy percentage; acts like carbon in strengthening
10xx
plain carbon steel
11xx
resulfurized carbon steel
41xx
Chromium, Molybdenum
43xx
nickel, chromium, molybdenum
52xxx
Chromium, usually 1% or higher, cheat tool steel
Safety in hardening
risk of damage from hardening (quench cracks)
Answers!!
Aluminum (Al)
<2 alloy percentage; Aids nitriding, restricts grain growth, removes oxygen in steel melting
Sulfur and phosphorous (S,P)
<0.5 alloy percentage ; Adds machinability, reduces weldability, ductility, and toughness
Chromium (Cr)
0.3-4 alloy percentage; Increases resistance to corrosion and oxidation, increases hardenability,
increases high temperature strength, can combine with carbon to form hard, wear resistant
microconstituents
Nickel (Ni)
0.3-5 alloy percentage; promotes austenitic structure, increases hardenability, increases
toughness
Copper (Cu)
0.2-0.5 alloy percentage; promotes tenacious oxide film to aid atmospheric corrosion resistance
Manganese (Mn)
0.3-2 alloy percentage; increases hardenability, lowers hardening temperature, promotes an
austenitic structure, combines with sulfur to reduce its adverse effects
Silicon (Si)
0.2-2.5 alloy percentage; removes oxygen in steelmaking, improves toughness, increases
hardenability
Molybdenum (Mo)
, 0.1-0.5 alloy percentage ; promotes grain refinement, increases hardenability, improves high
temperature strength
Vanadium (V)
0.1-0.3 alloy percentage; promotes grain refinement, increases hardenability, will combine with
carbon to form wear resistant microconstituents
Boron (B)
0.0005-0.003 alloy percentage; added in small amounts to increase hardenability
Lead (Pb)
<0.3 alloy percentage; added only to aid machinability
Nitrogen (N)
<0.1 alloy percentage; acts like carbon in strengthening
10xx
plain carbon steel
11xx
resulfurized carbon steel
41xx
Chromium, Molybdenum
43xx
nickel, chromium, molybdenum
52xxx
Chromium, usually 1% or higher, cheat tool steel
Safety in hardening
risk of damage from hardening (quench cracks)
