Polycrystalline diamond material with thermally-stable catalyst-free region

文件类型：PDF文档
文件大小：1541K
A method for forming a sintered polycrystalline diamond material comprising the steps of combining diamond grains with a catalyst material, such as a Group VIII element, the diamond grains having an average particle size of 0.03 mm or more, pressurising the mixture under elevated temperature to form a polycrystalline diamond material having a diamond content of at least 93% by volume and a working surface, treating a first region 28 to render it free of the catalyst material while allowing catalyst material to remain in a second region 34 where the first region extends a depth from the working surface of from 0.01 to 0.1 mm. Also disclosed are earth boring bits utilising the polycrystalline diamond material in cutting elements.