Elements faced with superhard material

摘要

A preform cutting element, for use on a rotary drill bit, includes a facing table of polycrystalline diamond bonded to a tungsten carbide substrate, a cutting edge being formed by part of the peripheral surface of the facing table. The rear surface of the facing table is integrally formed with a plurality of spaced elongate ribs which project into the substrate, at least the majority of the ribs being located in the vicinity of the cutting edge. The ribs may intersect the cutting edge and extend only part way across the facing table from the cutting edge. The ribs may vary in width and/or depth.