Grinding cermets with diamond wheels

Abstract

1. It is shown that the chromium-carbide-base cermets cannot be machined by grinding with white corundum wheels or green silicon carbide wheels since this produces an unsatisfactory surface finish and reduces the bending strength of the material by 29%. 2. It has been found that this type of material can be satisfactorily ground with diamond wheels at the usual peripheral speeds with cooling and at increased speeds (to 35 m/sec) without cooling. The bending strength of ground specimens remained the same as the strength of specimens obtained by the powder metallurgy methods while the quality of surface finish reached the 8-th class (GOST 2789-59). 3. If no high efficiency of machining is required the chromium carbide parts can be satisfactorily machined by the electrospark method. In this case the strength of specimens can even slightly increase owing to the removal of the defects produced in the surface layer by compacting and sintering.