302. Which is incorrect statement about results of hot working
A.Annealing operation is not necessary
B.Power requirements are low
C.Surface finish is good
D.Grain refinement is possible
303. Forging of plain carbon steel is carried out at
A.750°C
B.900°C
C.1100°C
D.1300°C
304. Which of the following materials can't be forged
A.Wrought iron
B.Cast iron
C.Mild steel
D.High carbon steel
305. Swaging
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 the heated tube or shell
D.Is a forging method for reducing the diameter of a bar and in the process making it longer
306. Metals like lead and in are hot worked at temperatures around
A.500-600°C
B.200-300°C
C.100°C
D.Room temperature
307. Mechanical properties of the metal improve in hot working due to
A.Recovery of grains
B.Recrystallisation
C.Grain growth
D.Refinement of grain size
308. The following type of deformation of metals takes place in cold working and hot working
A.Elastic deformation
B.Plastic deformation
C.Viscous deformation
D.Isotropic deformation
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