High-Efficiency Grinding of Cermet.

Abstract

TiC-TiN-cermet cutting tools are coming into wide use today in metalworking industries because of their excellent properties. Particularly, improved toughness of cermet with increasing content of nitrogen makes applications for milling or drilling cutters possible. However, it is quite difficult to grind cermet with high efficiency because of its high degree of hardness and toughness. This results in the rapid wear of the diamond grains, and the need for frequent dressing of the grinding wheel surface. In this study, three different kinds of cermet are ground with a surface grinding machine using a resinoid bonded diamond wheel. The measurements of grinding force, surface roughness and grinding ratio are carried out to obtain a guide for high-efficiency grinding of cermet. To achieve the stable cermet grinding, it is important to take full advantage of the self-sharpening phenomenon of the grinding wheel. With respect to the grinding wheel, the friable grinding wheel will be suitable to attain the stable grinding processes. However, the surface roughness obtained is large and, therefore, finish grinding with a finer grinding wheel should be carried out to meet the demand for the cutting inserts.