Partial heat treatment method in salt bath at low temperature

摘要

This invention relates to a surface heat treatment method in a salt bath at low temperature, suitable for partially hardening the surface of a workpiece through heat treatment, including plating the surface of a workpiece with a first metal layer; partially peeling the first metal layer; heat treating the workpiece at a temperature of 400 to 500° C. for a predetermined period of time; and totally peeling the first metal layer. Thereby, low-temperature heat treatment is effective at heat treating the workpiece while minimizing deterioration of corrosion resistance.