1. Primary deformation zone in metal cutting operation is located at:
a) Around shear plane
b) Tool chip interface
c) Tool work piece interface
d) Tool face
Explanation: Primary deformation is the zone where maximum deformation occurs and occurs around the shear plane.
2. Secondary deformation zone in metal cutting operation is located at:
a) Shear plane
b) Tool chip interface
c) Tool work piece interface
d) Tool face
Explanation: Secondary deformation zone has medium level of deformation and generally occurs in tool chip interface.
3. Temperature rise in primary deformation zone is generally due to:
a) Plastic deformation of metal in shear zone
b) Friction between tool and chip
c) Rubbing action of tool piece with work piece
d) None of the mentioned
Explanation: Due to plastic deformation of metal during chip formation, there is a gradual rise in temperature.
4. Temperature rise in secondary deformation zone is generally due to:
a) Plastic deformation of metal in shear zone
b) Friction between tool and chip
c) Rubbing action of tool piece with work piece
d) None of the mentioned
Explanation: Temperature rises due to relative motion between chip and tool against some friction. Friction is responsible for the heat generation.
5. If heat transferred to the atmosphere is neglected, then the average amount of heat in % carried away by chips is nearly equal to:
a) 70
b) 15
c) 20
d) 96
Explanation: About 70% of the heat is carried away by chips, if heat transferred to surrounding is neglected.
6. If heat transferred to atmosphere is neglected, then the average amount of heat in % transferred to tool is nearly equal to:
a) 70
b) 15
c) 20
d) 96
Explanation: About 15% of the total heat is transferred to tool, if heat transferred to the surrounding is neglected
7. If heat transferred to atmosphere is neglected, then the average amount of heat in % transferred to work piece is nearly equal to:
a) 70
b) 15
c) 20
d) 96
Explanation: About 15% of the total heat is transferred to work piece if heat transferred to the surrounding is neglected.
8. By increasing cutting speed, amount of heat generated
a) Increases
b) Decreases
c) Remains constant
d) None of the mentioned
Explanation: With increase in cutting speed, friction increases and hence the amount of heat generated increases.
9. By increasing feed rate, amount of heat generated
a) Increases
b) Decreases
c) Remains constant
d) None of the mentioned
Explanation: With an increase in feed rate, friction time for generating heat decreases and hence the amount of heat generated increases.
10. Amount of heat generated in shear plane is:
a) Directly proportional to shear angle
b) Inversely proportional to shear angle
c) Does not depend on shear angle
d) None of the mentioned
Explanation: With an increase in shear angle amount of plastic deformation decreases and hence the amount of heat generated decreases.