hardness of the work and tool material at the operating temperature

amount and distribution of hard constituents in the work material

degree of strain hardening in the chip

all of these

carbon tool steels

tungsten carbide tools

high speed steel tools

ceramic tools

adhesion of metals

oxidation of metals

diffusion of metals

all of these

increase in cutting temperature

weakening of tool

friction and cutting forces

all of these

cracking at the cutting edge due to thermal stresses

chipping of the cutting edge

plastic deformation of the cutting edge

all of these