| 摘要 |
An abrasive compact comprising 40 to 90 volume percent of cubic boron nitride (CBN) crystals bonded by 60 to 10 volume percent of a bonding matrix comprised mainly of an intimate mixture of silicon nitride and metallic diboride MB2 where M represents metal atoms chosen from the group of titanium, zirconium and hafnium atoms. The compact may be produced by a method which comprises intimately mixing particulate CBN crystals with a bonding agent in the proportion 95 to 60 volume percent of CBN and 5 to 40 volume percent of bonding agent, the bonding agent containing the metal atoms in the atomic proportions Si30M70 to Si85 M15, subjecting the mixture of CBN crystals and bonding agent to temperatures in the range 900 degrees to 1800 degrees C. and pressures in the range 5 to 70 Kilobars, and maintaining the temperature and pressure conditions for a period of at least about 30 seconds, sufficient to cause most of bonding agent to form the bonding matrix.
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