309. Pick up wrong statement about results of hot working
A.Poor surface finish
B.Improvement in mechanical properties
C.Refinement of grain structure
D.Close tolerances obtained

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310. The important mechanical property for a material to be successfully rolled or forged is
A.Brittleness
B.Malleability
C.Elasticity
D.Machinability

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311. The important mechanical property of a material for extrusion purposes is
A.Continuity
B.Ductility
C.Elasticity
D.Plasticity

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312. The increase in hardness due to cold working is called
A.Cold hardening
B.Hot hardening
C.Work hardening
D.Age-hardening

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313. In which type of extrusion process, the movement of the extruded product is in the direction opposite to that of the deforming force
A.Direct
B.Forward
C.Backward
D.Die extrusion

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314. Hot working operation is carried at
A.Recrystallisation temperature
B.Near plastic stage temperature
C.Below recrystallisation temperature
D.Above recrystallisation temperature

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315. Roll forging
A.Causes a steadily applied pressure instead of impact force
B.Is used to force the end of a heated bar into a desired shape
C.Is a forging operation in which two halves of a rotating die open and close rapidly while impacting the end of heated tube or shell
D.Is forging method for reducing the diameter of a bar and in the process making it longer

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