SUMMARY
History of ion nitriding started in 30s but it was not until 70s of the last century when the significant progress in the electronics and computers allowed manufacturing of the proper power supplies for controlling plasma process and since then development of plasma nitriding and nitrocrburising was accelerated. In the United States ion nitriding and ion nitrocarburising are applied for hardening the surfaces of many parts and tools made of various grades of steel and also titanium and nickel alloys. Ion nitriding methods are applied for parts which can not be treated with gas nirtiding method. The best applications of these methods are for parts made of the sintered metal products of the low density, especially for those made of the stainless steels, parts and tools requiring extensive masking, parts made of the high alloy steels such as stainless steels, tools of the large size specifically those made of the gray cast iron, very long parts such as shafts, extruder feedscrews, etc.

Keywords
Ion (plasma) nitriding, ion (plasma) nitrocarburising, mechanical masking, sintered (powder) metal products, stainless steels, metal forming tools.

¹ Advanced Heat Treat Corp., Monroe, USA