Affinity of Diamond for Metals

Summary The fundamental direction on the development of bonding matrixes for diamond grinding wheels and the basic interpretation of the affinity of diamond for various work materials in machining process are discussed on the bases of the wetting test of sn on the surfaces of diamond evaporated with pure metals and of the thermal erosion test of diamond specimen embedded in the powder of various pure metals. Lower affinities in term of Van der Waals forces are observed for all combinations of diamond and metals of low melting points. In the thermal erosion test, remarkable change in appearance is observed on the surface of diamond heated in respective powders of Ti, Ni, Cr and Co. In the wetting test up to 950 °C, metal evaporated surfaces of diamond are lightly eroded in the cases of Bi, Ag and Ti and are graphitized in the case of Mn. Drastic changes in Wa/Wc are observed in the cases of Ni, Cr, Fe and Co accompanied with heavy thermal erosion.