Source:     Journal Materials Science, vol.25 (1990) pp.2527-2531
 

Abstract:  Different machining processes such as ultrasonic machining and grinding by a diamond wheel produce varying degrees of surface damage. The amount of surface damage appeared to be related to the type of machining process. However, the degree of surface damage could not be related to the surface roughness for different machining processes. The surface damage created by the machining process can be fully or partially recovered by heat treatment subsequent to machining. The degree of recovery by heat treatment seems to be dependent on the severity of the surface damage during the machining process. Observation of the surface microcracks and determination of the fracture toughness of the material after machining or heat treatment indicated recovery of some of the microcracks during the heat treatment.