Synthesis of polycrystalline cubic boron nitride

摘要: A sintered polycrystalline compact of cubic boron nitride is made by forming a mixture about 45 to 65 percent weight (cBN), from 30 hexagonal (hBN), and 2 7 an aluminum containing material, preferably nitride, cobalt aluminide having melting temperature lower than the phase. The cBN crystals, hBN adjuvant materials compacted into preforms subjected heat treatment in non-oxidizing atmosphere. are placed onto cemented tungsten carbide substrate elevated pressure conditions at which thermodynamically stable. maintained for time sufficient permit infiltration phase matrix sinter compact. Typically, infiltrated with characterized substantial intercrystalline bonding, has superior abrasive wear resistance, chemical impact thermal conductivity stability. Further, technique produces that can be machined more efficiently EDM.