| 摘要 |
PURPOSE:To form a coating layer with superior wear resistance and high adhesive strength to a metallic substrate by applying paste contg. a powdered mixture of WC with an Ni-Cr alloy, B, Si, C and Fe to the surface of the substrate and pressing and sintering the paste. CONSTITUTION:A powdered mixture of WC with an Ni-Cr alloy, B, Si, C and Fe having 1-10mum average particle size is converted into paste with a binder such as CMC, and the paste is applied to the surface of the spacer pad of a fuel assembly for a fast breeder. The applied paste is pressed under >=100kg/cm<2> pressure in vacuum or an inert gas such as Ar and sintered by heating at 1,020- 1,080 deg.C to form a hard layer with superior wear resistance. A coating layer of an Ni-P alloy, an Ni-B alloy or Cu may be formed beforehand on the surface of the spacer pad by electroless plating or other method to remarkably enhance the adhesive strength of the wear resistant hard layer. |
