摘要 |
60-SD-134 IMPROVED HIGH PRESSURE PROCESS FOR PREPARING DIAMOND WIRE DIE COMPACTS A process improvement is disclosed for making diamond wire die compacts of the type which are generally described as an inner polycrystalline diamond mass surrounded by and bonded to a mass of metal bonded carbide, such as cobalt cemented tungsten carbide. It is known to make these dies by high pressure-high temperature processes, typical conditions being 50 kbar and temperatures in excess of 1300.degree.C. The improvement comprises disposing within the reaction sub-assembly (e.g. metal carbide and diamond within a zirconium cup) a set of discs of specific materials of a specific thickness range and in specified arrangements. On one side of the mass of metal carbide and diamond is disposed one disc of a diamond catalyst/solvent and one disc of a refractory metal such as molybdenum, and on the other side are disposed at least two discs of one or more transition metals such as zirconium. These discs are generally placed inside the sub-assembly cup and have a thickness range of 25-102 microns. By means of this process modification, process yields have been significantly improved through decreasing the occurrence of defects in the dies and by decreasing the reaction time. |