| 摘要 |
PROBLEM TO BE SOLVED: To impart high heat conductivity as well as high strength characteristics by molding a mixture of Si powder having a specified oxygen content and oxide of Y, Yb or Sm, nitriding the resultant molding and firing it at a specified temp. SOLUTION: A mixture of 80-99 wt.% high purity Si powder having <=1 wt.% oxygen content and 1-20 wt.% powder of an oxide represented by the formula Ln2 O3 (Ln is at least one selected from Y, Yb and Sm) is molded. The resultant molding is nitrided at <=1,400 deg.C in an nitrogen-contg. atmosphere and then fired at 1,700-1,950 deg.C in a nitrogen-contg. atmosphere to obtain the objective dense sintered compact having 85-99.9% relative density, >=70 W/mK heat conductivity and >=600 MPa three-point bending strength. When the powdery starting material is mixed with a reducing coating agent and heat-treated under reduction, the heat conductivity of the sintered compact can further be enhanced. |
