666. For fast metal removal rate on lathe, it is recommended to
A.Increase speed
B.Use roughing cut
C.Use carbide tool
D.Use abundant supply of coolant

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667. Segmented chips are formed when machining
A.Ductile metal
B.Brittle material
C.Heat treated material
D.With lot of pressure and heat against the tool

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668. Machinability
A.Tends to increase with increase in hardness
B.Tends to decrease with increase in hardness
C.Remains-unaffected with hardness
D.Option (B) is correct in general, but it can be drastically influenced by strain hardening and microstructure

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669. Machinability depends on
A.Microstructure, physical and mechanical properties and composition of workpiece material
B.Cutting forces
C.Type of chip
D.Tool life

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670. Machinability tends to decrease with
A.Increase in hardness and increase in tensile strength
B.Increase in strain hardening tendencies
C.Increase in carbon content, hard oxide and carbide
D.Decrease in grain-size

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671. Machinability can be calculated and predicted by following factor
A.Tensile strength
B.Brinell hardness
C.Shear angle
D.All of the above

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672. Shear angle varies with
A.Different materials and with tool geometry
B.Cutting speed
C.Feed
D.Machine used

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