某些机械零件如内燃机气阀挺杆、摇臂以及转子发动机的刮片等,要求局部有抵抗不同条件摩擦的能力。通常采用局部冷激铸铁件。形成以渗碳体为基体的白口铸铁组织,可具有相当高的抗磨料磨损特性,能胜任摩擦应力大、润滑困难的工作状况。然而,铸铁件的局部冷激铸造控制因素很复杂,而且受零件的结构形状、铁水成分、以及其后机械加工等问题的限制。本文所要介绍的方法是在一般铸造零件表面用等离子弧处理,使所需部位形成白口组织的工艺方法。这种方法不但可以避免冷激铸造所遇到的许多困 Some mechanical parts such as internal combustion engine valve lifter, rocker and rotor motor blades, etc., require local resistance to friction under different conditions. Usually use local chilled cast iron parts. The formation of cementite body as the base of white cast iron, can have a very high abrasion resistance, able to handle frictional stress, lubrication difficult working conditions. However, the local chill cast control of castings is complicated and is limited by the structural shape of the part, the hot metal composition, and the consequent machining problems. This article describes the method is to cast the surface of the general use of plasma arc treatment, the required parts of the formation of white tissue processes. This method not only avoids many of the difficulties encountered in cold shock casting