surface hardened stainless steel with improved wear resistance and low static friction properties

摘要

The invention relates to the use of PVD technique for the application of a low static friction and wear resistant coating consisting essentially of titanium nitride or a diamond-like carbon-DLC, with or without an addition of tungsten carbide, on a stainless steel, in one and the same operation as the surface hardening of the stainless steel. In this way, in one single operation, a low static friction is obtained on a very hard and wear resistant surface. Moreover, the dimensions of the work-piece are maintained unaltered, which makes the invention very useful in the production of, e.g., cam followers, cylinder tubes and piston rods for shock absorbers. The used stainless steel has the following composition (in weight %): carbon max about 0.1; nitrogen max about 0.1; copper from about 0.5 to about 4; chromium from about 10 to about 14; molybdenum from about 0.5 to about 6; nickel from about 7 to about 11; cobalt 0 to about 9; tantalum max about 0.1; niobium max about 0.1; vanadium max 0.1; tungsten max about 0.1; aluminum from about 0.05 to about 0.6; titanium from about 0.4 to about 1.4; silicon max about 0.7; manganese max about 1.0; iron balance, and normally occurring usual steelmaking additions and impurities.