TiN has a Vickers hardness of 2400, a modulus of elasticity of 251 GPa, a thermal expansion coefficient of 9.35×10−6 K−1, and a superconducting transition temperature of 5.6 K.[1][2]
TiN will oxidize at 800 °C in a normal atmosphere. It is chemically stable at 20 °C, according to laboratory tests, but can be slowly attacked by concentrated acid solutions with rising temperatures.[1]
TiN has infrared (IR) reflectivity properties, reflecting in a spectrum similar to elemental gold (Au), which gives it a yellowish color. Depending on the substrate material and surface finish, TiN will have a coefficient of friction ranging from 0.4 to 0.9 against another TiN surface (non-lubricated). The typical TiN formation has a crystal structure of NaCl-type with a roughly 1:1 stoichiometry; TiNx compounds with x ranging from 0.6 to 1.2 are, however, thermodynamically stable.[3] A thin film of TiN was chilled to near absolute zero, converting it into the first known superinsulator, with resistance suddenly increasing by a factor of 100,000.[4]