| 摘要 |
PURPOSE:To thermal-spray SiC or Si3N4 by thermal-spraying the material obtained by depositing a low-m.p. oxide-based ceramic on the surfaces of the particles of ceramics such as SiC and Si3N4 at the time of forming the title thermal-spraying ceramic layer of the SiC, Si3N4, etc., having excellent hardness and resistance to heat and wear on the surface of a substrate. CONSTITUTION:The thermal-spraying ceramic layer of the carbide and nitride such as SiC and Si3N4 having excellent hardness and resistance to heat and wear is formed on the surface of the parts of an internal-combustion engine such as a piston to be slid at high temp. In this case, a substrate thermal- spraying layer 5 of an alloy such as Ni-Al and Ni-Cr having a thermal expansion coefficient intermediate to those of a base material 1 of an Al alloy, etc., and the above-mentioned ceramic is formed on the surface of the base material 1. The material obtained by depositing the fine powder of the oxide-based ceramic such as Al2O3 and spinel on the powder of SiC or Si3N4 having the higher m.p. than the ceramic is thermal-sprayed thereon. When the Al2O3 8, etc., are melted and resolidified, the powder 7 of SiC or Si3N4 having a high m.p. and easy to sublimate is bound, and the thermal-spraying layer 6 of SiC or Si3N4 can be formed on the substrate layer 5 with excellent adhesive strength. |
