Nitreg~(~R) ONC~R Where Corrosion Resistance Wear Requirements Finally Meet

摘要

Nitreg~(~R)-ONC~R is a modern combination of the proven Nitreg~(~R) potential-controlled nitriding process and a post-treatment oxidation stage, with an optional impregnation of the surface with a liquid corrosion inhibitor. It has been successfully applied to enhance the service life of parts used in various applications such as automotive, hydraulics, sporting goods, appliances, industrial machinery and tooling. The treatment is applied most frequently to low-alloyed structural steels, exposed to particularly intense corrosion hazards, while requiring improved wear resistance. The ONC~R part of the treatment provides a substantial enhancement of the corrosion resistance of nitrided surfaces. In a recent development the application of the treatment was extended to some stainless steels. Nitrex has performed extensive corrosion resistance studies, using the salt spray test (ASTM B-117). Metallographical analysis of material samples was used to correlate the corrosion behavior with thickness and structure of the nitrided layer. Successful industrial applications of the method are reviewed.