Nitrogen-Based Protective Gas Atmosphere.

Nitrogen-based protective gas atmospheres can be adapted to the various heat treatment procedures. A report is given concerning neutral atmospheres which were developed on a nitrogen base with the addition of hydrogen and/or carbon, and also concerning nitrogen-based atmospheres with the addition of methanol for carburization and carbonitriding. Examples of applications of these types of atmospheres are cited, and the advantages of their use are indicated, including an improvement in boundary oxidation and decarburization, uniformity of carburization, simple and reliable monitoring of the carbon level, economy and safety.