323. Case hardening is the only method suitable for hardening:
A.High alloy steel
B.High carbon steel
C.Low-carbon steel
D.High speed steel

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324. Which of the following element in steel directly affects the critical temperature of the steel to be heat-treated
A.Sulphur
B.Phosphorus
C.Carbon
D.Chromium

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325. High alloy steels have to be heated slowly and uniformly for hardening, to avoid
A.Scaling
B.Shrinkage
C.Warpage
D.Segregation

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326. Overheating high alloy steels when pack hardening must be avoided to prevent
A.Low hardness and shrinkage
B.Extreme hardness and brittleness
C.Distortion
D.Scale formation

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327. A small selected portion of the job can be hardened by
A.Flame and induction hardening
B.Pack hardening
C.Cyaniding
D.Nitriding

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328. Which of the following is not the objective of annealing
A.Remove internal stresses
B.Refine grain size
C.Refine structure
D.Improve machinability

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329. Which of the following is a case hardening process
A.Spherodising
B.Tempering
C.Sheradising
D.Cyaniding

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