Heat treating a cast part e.g. tension disk or braking drum, of braking system of vehicle i.e. car, comprises ion nitriding a cast part to form a surface layer of iron nitride on cast part with specific amount of thickness

摘要

The method comprises ion nitriding a cast part to form a surface layer of iron nitride on the cast part. The surface layer of iron nitride has a thickness of 10-20 mu m.