| 摘要 |
PURPOSE:To produce the high-hardness microcrystal sintered compact capable of attaining an excellent finished-surface roughness when used for the edge of a cutting tool, a drawing die, etc., and excellent in wear resistance. CONSTITUTION:This sintered compact contains 60-94vol.% of diamond having <=3mum grain diameter, 1-40vol.% of high-pressure phase-type boron nitride having <=3mum grain diameter and the balance diamond synthesizing metallic catalyst (contg. >=5wt.% of iron-family metal), and a solid soln. is formed at the grain boundary between the diamond and boron nitride as the structure. Meanwhile, such a sintered compact is also obtained by bringing a metal or alloy contg. >=5wt.% iron-group metal into contact with the amorphous carbon formed from the resin contg. the diamond powder having <=3mum grain diameter and the high-pressure phase-type boron nitride powder having <=3mum grain diameter and pressure-sintering the mixture at >=1350 deg.C and at a pressure in the thermodynamic diamond stabilizing region. |
