In one aspect of the invention, a high impact resistant tool includes a superhard material bonded to a cemented metal carbide substrate at a non-planar interface. The superhard material has a substantially pointed geometry with a sharp apex having a radius of curvature of 0.050 to 0.125 inches. The superhard...http://www.google.es/patents/US8109349?utm_source=gb-gplus-sharePatente US8109349 - Thick pointed superhard material
