Methods of treating preform elements including polycrystalline diamond bonded to a substrate

Abstract

A method of thermally treating a preform element, of the kind having a facing table of polycrystalline diamond bonded to a substrate of cemented tungsten carbide, is disclosed. The steps of the method are: (a) heating the element to a soaking temperature of about 600.degree. C., (b) maintaining the temperature of the element at that temperature for two to three hours, and (c) cooling the element to ambient temperature. These steps are preferably then followed by a flash heating cycle. These steps are: (d) heating the element to a temperature in the range of 750-850.degree. C., (e) maintaining the temperature of the element at that temperature for about four seconds, and (f) cooling the element to ambient temperature. This thermal treatment relieves residual stresses in the element in order to reduce the risk of cracking or delamination of the element in use.

Dependencies are inferred from the claim text.