| 摘要 |
1431693 Heat-treated coated diamonds DE BEERS INDUSTRIAL DIAMOND DIVISION Ltd 5 April 1974 [16 April 1973] 18268/73 Heading C7F A batch of individual, discrete uncoated diamond particles are coated with a metal capable of dissolving C but incapable of forming stable carbides under ambient temperature and pressure conditions, and the coated batch is heat-treated above 500 C but below the melting point of the metal and the graphitization temperature of diamond, the coating and heating steps being performed in a non-oxidizing atmosphere to produce a batch of individual, discrete, metal-coated diamond particles. The metal may be Fe, Co, or Ni, applied electrolytically, electrolessly or by vacuum deposition; in an example a first layer of Ni is vacuum vapour deposited, heat-treated in vacuo at 800‹C for 2 hours, and electroless Ni plated. The non-oxidizing atmosphere may be He, Ar, H 2 , N 2 or a vacuum of 10<SP>-2</SP>mm Hg or better. The product may be incorporated in resin-or metalbonded abrasive wheels, saws, compacts, crowns, or single-point tools. |
