1. Crater wear occurs mainly on the
a) nose part, front relief face and side relief face of the cutting tool
b) face of the cutting tool at a short distance from the cutting edge only
c) cutting edge only
d) front face only
Explanation: Crater wear occurs on the rake face of the tool, while flank wear occurs on the relief (flank) face of the tool.
2. Flank wear depends upon the
a) hardness of the work and tool material at the operating temperature
b) amount and distribution of hard constituents in the work material
c) degree of strain hardening in the chip
d) none of the mentioned
Explanation: Flank wear occurs as a result of friction between the progressively increasing contact area on the tool flank.
3. Crater wear is predominant in
a) carbon steels
b) tungsten carbide tools
c) high speed steel tools
d) ceramic tools
Explanation: Crater wear is usually found while machining brittle materials and tungsten carbide tools favour this phenomenon.
4. Flank wear is due to the abrasive action of hard mis-constituents.
a) True
b) False
Explanation: Flank wear is due to the abrasive action of hard mis-constituents including debris from built up edge as the work material rubs the work surface.
5. Crater wear is mainly due to the phenomenon is known as
a) adhesion of metals
b) oxidation of metals
c) diffusion of metals
d) none of the mentioned
Explanation: Flank wear is due to the abrasive action and crater wear is due to diffusion of metals.
6. Crater wear leads to
a) increase in cutting temperature
b) weakening of tool
c) friction and cutting forces
d) all of the mentioned
Explanation: all of the mentioned
7. Crater wear is usually found while machining ductile materials.
a) True
b) False
Explanation: Crater wear is usually found while machining brittle materials.
8. The tool may fail due to
a) cracking at the cutting edge due to thermal stresses
b) chipping of the cutting edge
c) plastic deformation of the cutting edge
d) all of the mentioned
Explanation: all of the mentioned
9. Flank wear occurs mainly on the
a) nose part, front relief face and side relief face of the cutting tool
b) face of the cutting tool at a short distance from the cutting edge only
c) cutting edge only
d) front face only
Explanation: Crater wear occurs on the rake face of the tool, while flank wear occurs on the relief (flank) face of the tool.
10. Tool life is measured by the
a) number of pieces machined between tool sharpenings
b) time the tool is in contact with the job
c) volume of material removed between tool sharpenings
d) all of the mentioned
Explanation: all of the mentioned