ABSTRACT: In this paper am observed the discharging and welding phenomena which exist between diamond’S coating films OY between coating film and metal grit during the spark sintering process of the Ti-coating diamond or Ti/Ni coating diamond and the film’s effects on products’bending strength and sit exposing height have been studied. The results showed that Ti Or Ti/Ni-coating diamond can participate in the pulse sintering during the powder metallurgy process because of the metallic properties of the coating film. For this reason, the holding capability of diamond grit in metal matrix can be increased. And the products’bending strength and grit exposing height are improved. Accordingly, the life and sharpness of the diamond toolsAre increased greatly.

KEYWORDS spark sintering, metal coating, bending, strength, grit exposing height