Cutting elements and methods of manufacture thereof

摘要

A cutting element for a rotary drill bit includes at least one insert (20) of polycrystalline diamond of a kind incorporating a carbonate as a sintering binder-catalyst. The insert (20) is mounted by being at least partly surrounded by a support body (21) of conventional polycrystalline diamond of a kind incorporating a sintering binder-catalyst selected from cobalt and other iron group elements or alloys thereof. The insert (20) and support body (21) may be integrally bonded to a substrate during manufacture. Either the insert (20) or support body (21) may be pre-sintered or sintered during formation of the cutting element.