| 摘要 |
PURPOSE:To obtain the above sintered product which is used as a cutting tool, because of its high abrasion resistance and high resistance to breaking-off, by combining cubic BN, AlN, AlB2, metal or alloy or Co and/or Ni as major components, Al2O3 at a specific volume ratio and a metal compound of high melting point and calcining the mixture. CONSTITUTION:Starting materials corresponding to 10-80vol.% of cubic BN of less than 15mu average particle size; 1-5vol.% of AlB2 and/or AlB12; 1-5vol.% of TiB2; 0.1-2vol.% of metal or its alloy containing mainly Co and/or Ni; 7.5-80vol.% of Al2O3 of less than 1.0mu average particle size in an amount corresponding to (0.5-0.956)/(0.5-0.044) volume ratio of Al2O3/the high melting metallic compound; and 3.75-40vol.% of high melting point metallic compound which is composed of at least one selected from carbides and nitrides of Ti, Zr, Hf, At, Nb or V, carbides of W and a solid solution containing the same, are mixed, crushed, formed then sintered at 1,300-1,600 deg.C under a pressure of 40-60kb at 5-15min. |
