| 摘要 |
1496106 Abrasive diamond compact DE BEERS INDUSTRIAL DIAMOND DIVISION Ltd 8 Oct 1976 [27 Oct 1975] 41950/76 Heading C4V A compact for use in cutting, drilling, grinding and lapping comprises abrasive diamond particles bonded into a hard conglomerate by a bonding matrix comprising a solvent metal for diamond, and boron, the abrasive particles constituting greater than 70% by volume of the compact and the boron being present in an amount not exceeding 1% by weight of the diamond particles. The solvent metal may be Co, Fe, Ni, Mn, Ta or an alloy of one or more thereof. The compact may be made by subjecting a mixture of diamond particles, powdered solvent metal and boron powder to suitable temperatures and pressures, usually 40-70 kilobars at 1200-1600‹ C., or by an infiltration process in which a layer of diamond particles and boron powder is placed on a cemented tungsten carbide backing and heated to above 1200‹ C. at above 50 kilobars pressure whereby the cementing metal from the backing infiltrates into the diamond layer to form the desired compact which is also bonded to the backing. In either process, the boron powder may be omitted and boron-doped diamond particles used as boron source. |
