Nitrides

Abstract

Nitrides may be classified as being ionic or salt‐like, metallic, nonmetallic or diamond‐like, or volatile. Additionally, sulfur and phosphorus form polymeric nitride species. Whereas many nitrides exist, only a few are produced commercially. Transition‐metal binary nitrides, made on a small scale, are used for high strength and hardness primarily as refractory coatings. Boron, aluminum, and silicon nitrides are produced on much larger scales and find use as refractories, ablative materials, abrasives, and coatings. Lithium nitride finds application in batteries and catalysts. Gallium and indium nitrides are used in such optoelectronic devices as light‐emitting diodes. The properties of transition‐metal metallic nitrides and the diamond‐like nonmetallic nitrides are described. The manufacture and processing of nitride coatings by case hardening is presented as well as the processing of the structurally important silicon nitride.