What is "titanium nitride"

n. (context chemistry English) A very hard, golden-coloured ceramic material, TiN; used in refractory, alloys, cermets, and semiconductors

Titanium nitride (sometimes known as tinite) is an extremely hard ceramic material, often used as a coating on titanium alloys, steel, carbide, and aluminium components to improve the substrate's surface properties.

Applied as a thin coating, TiN is used to harden and protect cutting and sliding surfaces, for decorative purposes (due to its gold appearance), and as a non-toxic exterior for medical implants. In most applications a coating of less than is applied.