351. Toughness of a material means
A.Strength
B.Machinability
C.Stress relieving
D.Softening

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352. White cast iron is produced by the following operation on grey cast iron
A.Rapid cooling
B.Slow cooling
C.Rapid heating
D.Tempering

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353. The constituents of Hayness stellite, having superior performance than HSS are
A.Tungsten, chromium and vanadium
B.Tungsten, chromium and cobalt
C.Tungsten, molybdenum and cobalt
D.Cobalt, nickel and aluminium

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354. Line A1 on iron-carbon diagram indicates
A.The begining of transition from austenite to ferrite
B.Completion of austenite transition to ferrite and pearlite
C.Limit of carbon solubility in austenite
D.All or the above

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355. Troostite is the structure obtained by
A.Quenching austenite
B.Quenching austenite and then heating into the range of 200° to 375°C
C.Quenching austenite and then heating into the range of 375°-660°C
D.Quenching austenite and then heating into the range of 660°-700°C

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356. The process in which Steel is coated with a thin layer of phosphate is known as
A.Phosphorising
B.Sheradising
C.Anodising
D.Parkerising

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357. Eutectoid composition of carbon steel at room temperature is known as
A.Pearlite
B.Ferrite
C.Cementite
D.Martensite

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