| 摘要 |
PURPOSE:To obtain a boron nitride-base material sintered under superhigh pressure for a cutting tool and a wear-resistant tool with superior hardness, toughness, wear resistance and heat resistance by sintering powder of cubic system boron nitride (CBN) with Al and Al2O3 or AlN as reinforcing binders at high temp. under high pressure. CONSTITUTION:A mixture of 40-90vol% CBN powder with 2-20wt% Al powder and 5-40wt% Al2O3 and/or AlN as reinforcing binders is charged into a vessel made of mild steel, vaccum-degassed, tightly sealed, and press-sintered in a superhigh pressure and high temp. generator. Wurtzite type boron nitride (WBN) may be substituted for part of the CBN in 0.05-1 volume ratio of WBN/CBN, and to the binding metal may be added 0.5-10wt% one or more among Ni, Al, Co, Si and Cr. A high hardness BN-base sinteed material having a tough structure contg. CBN particles enveloped in the reinforcing and binding metal in 0.1-1mum thickness is obtd. |
