1999 年 48 巻 6 号 p. 541-545
Symmetrically graded materials of the Al2O3-BN/TiC/Ni were fabricated by SHS/HIP. High residual compressive stresses were produced in the outer layer due to the thermal expansion mismatch between the outer Al2O3-BN ceramic and the inner TiC/Ni cermet layer. The dispersion of BN in the Al2O3 layer increased the residual stress to higher levels than that induced in the Al2O3/TiC/Ni system. The BN has the layer structure with cleavage faces. The tribological properties of the outer Al2O3-BN layer were investigated at room temperature and 500°C in air. The friction coefficient of the outer layer was lower than that of monolithic Al2O3, especially at 500°C. The residual compressive stress was found to improve wear resistance of the surface layer.