CWB Module 22 CORRECT 100%
Complete the following:
a) Chromium stabilizes the _____ form of iron
b) Nickel stabilizes the _____ form of iron - ANSWERa) bcc
b) fcc
If a straight chromium steel of 18% Cr and < 0.1 % C is heated to 1000°C will it
transform to austenite or remain as ferrite? - ANSWERremain as ferrite
What is the predominant structure of an 18% Cr, 8% Ni steel at room temperature? -
ANSWERaustenite
The chromium content of a stainless steel is 20%. Is it likely this is a martensitic
grade? - ANSWERNo, Martensitic grade is 18% to 11.5% Cr
A 14% Cr martensitic steel heated to 1000°C and air cooled produces a) ferrite
b) aus1enite
c) martensite - ANSWERc) martensite
Does an austenitic stainless steel have a greater or lesser work hardening rate than
carbon steel? - ANSWERgreater
When a two layer overlay of stainless on carbon steel is made it is common practice
to use E308 for the second
layer and E _____for the first layer - ANSWER(E309) on top of the carbon and then
E308
Weld metal containing large amounts of ferrite and is exposed to high temperature
service may:
a) suffer embrittlement due to sigma formation
b) have improved ductility due to ferri1e growth
c) become air hardening - ANSWERa) suffer embrittlement due to sigma formation
A carbon steel component operates satisfactorily at 500°C under a stress of 50MPa.
If 304 stainless were substituted, up to what level could the temperature be raised? -
ANSWER600°C, 20% more then carbon
The loss of corrosion resistance due to carbide formation and chromium depletion is
known as:
a) sigma formation
b) sensitization
c) stabilization - ANSWERb) sensitization
What maximum carbon level is usually specified to ensure freedom from
sensitization during welding?
a) 0.03%
Complete the following:
a) Chromium stabilizes the _____ form of iron
b) Nickel stabilizes the _____ form of iron - ANSWERa) bcc
b) fcc
If a straight chromium steel of 18% Cr and < 0.1 % C is heated to 1000°C will it
transform to austenite or remain as ferrite? - ANSWERremain as ferrite
What is the predominant structure of an 18% Cr, 8% Ni steel at room temperature? -
ANSWERaustenite
The chromium content of a stainless steel is 20%. Is it likely this is a martensitic
grade? - ANSWERNo, Martensitic grade is 18% to 11.5% Cr
A 14% Cr martensitic steel heated to 1000°C and air cooled produces a) ferrite
b) aus1enite
c) martensite - ANSWERc) martensite
Does an austenitic stainless steel have a greater or lesser work hardening rate than
carbon steel? - ANSWERgreater
When a two layer overlay of stainless on carbon steel is made it is common practice
to use E308 for the second
layer and E _____for the first layer - ANSWER(E309) on top of the carbon and then
E308
Weld metal containing large amounts of ferrite and is exposed to high temperature
service may:
a) suffer embrittlement due to sigma formation
b) have improved ductility due to ferri1e growth
c) become air hardening - ANSWERa) suffer embrittlement due to sigma formation
A carbon steel component operates satisfactorily at 500°C under a stress of 50MPa.
If 304 stainless were substituted, up to what level could the temperature be raised? -
ANSWER600°C, 20% more then carbon
The loss of corrosion resistance due to carbide formation and chromium depletion is
known as:
a) sigma formation
b) sensitization
c) stabilization - ANSWERb) sensitization
What maximum carbon level is usually specified to ensure freedom from
sensitization during welding?
a) 0.03%
