Crater wear starts at some distance from the tool tip because
Option (A)
Cutting fluid cannot penetrate that region
Option (B)
Stress on rake face is maximum at the region
Tool strength s minimum at that region
Tool temperature is maximum at that region
Correct Option:
Question Solution:
Diffusion phenomena occur when the interface temperature is so much high which are conducive for alloying atoms from the harder material (tool) to softer matrix (w/p chip), thereby increasing hardness and abrasiveness of chip become harder. After some time at 2-3 mm away from tool point, the tool material is dislodged and carried away by chips which produces crater. Hence diffusion phenomena is responsible for crater formation which takes place at 2 – 3 mm away from tip.