316. Beryllium is used chiefly as an alloy addition to copper to produce
A.Precipitation-hardenable alloy
B.Corrosion resistant alloy
C.High-strength alloy
D.Non-magnetic and non-sparking alloy

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317. Which of the following has maximum hardness
A.Austenite
B.Pearlite
C.Troostite
D.Martensite

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318. Which of the following is not the objective of normalising
A.Refine steel structure
B.Remove strains caused by cold working of metal
C.Remove internal stresses
D.Improve tensile strength

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319. The main purpose of heat treatment of steels is to change the
A.Chemical composition
B.Mechanical properties
C.Corrosion properties
D.Surface finish

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320. Low carbon steel can be hardened by
A.Hardening
B.Heating and quenching in oil
C.Heating and quenching in water
D.Carburising and cyaniding

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321. The hardening strains are reduced and the toughness of the part increased by the following process after hardening
A.Annealing
B.Carburizing
C.Tempering
D.Anodizing

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322. Hard alloy and tool steels are made easy machinable by following heat treatment
A.Case carburising
B.Tempering
C.Annealing
D.Normalising

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