| 摘要 |
It is known that a hardened chilled layer with a fine metallic composition having excellent abrasion resistance can be obtained if a sliding surface layer of an Fe- containing alloy component, such as a cam shaft used in a valve mechanism of an internal combustion engine, is rapidly melted by irradiating the surface layer with high- concentration energy such as a plasma jet, laser beam, etc. and is thereafter hardened by self-cooling. The abrasion resistance may be greatly enhanced if this remelting and hardening treatment is applied to a hardened chilled layer formed during casting the component. Furthermore, if a carbide-stabilizing agent such as Cr or Mo is added to the molten pool produced on the surface during the remelting and hardening treatment, a double carbide is produced in the hardened chilled layer and a high hardness can be obtained. For the sliding surface of a shaft member which is not used in as severe conditions as a cam of a cam shaft, even if the remelting and hardening treatment is performed in a spiral shape, the required abrasion resistance can be obtained, resulting in high productivity and good economy. <IMAGE> |
