| 摘要 |
PURPOSE:To produce the title BN sintered compact having excellent in resistance to heat, thermal shock, and corrosion, lubricity, electric insulating property, and thermal conductivity by mixing specified hexagonal BN powder and BC powder, compacting the mixture, and sintering the compact in an N2-contg. atmosphere. CONSTITUTION:From 60 to 99.9wt.% of the mixed powder of hexagonal BN, obtained by mixing 50-90pts. powder having 1-30m<2>/g specific surface by the BET method and 50-10pts. powder having >=100m<2>/g specific surface by the BET method, and 40-0.01wt.% BC powder having <=30mu particle diameter are wet-mixed, and dried to obtain granules. The granules are compacted at >=1,000kg/cm<2> pressure to obtain a compact, and the compact is heated to >=1,600 deg.C at the temp. increasing rate of >=20-100 deg.C/min in N2 or in a nonoxidizing atmosphere contg. N2, and then sintered for 2-10hr. Alternatively, the granules are packed in a graphite die, and hot-pressed at 200-400kg/cm<2> pressure and at >=1,800 deg.C. |
