Mechanical and tribological properties of TiN/Ti multilayer coating

A large area filtered arc deposition (LAFAD) technique was used to deposit TiN/Ti multilayer coatings with fixed TiN layer thickness and different Ti layer thickness. Nanoindention and pin-on-disk tribometer were used to characterize the hardness, elastic modulus, plasticity, friction coefficient, and wear rate of the multilayer coatings. The dependence of the mechanical and tribological properties of the coating on the Ti interlayer thickness was systematically studied. It was found that the increase in the Ti layer thickness resulted in a decrease in the effective hardness and elastic modulus, and an increase in the wear rate, plasticity, and toughness. The coatings with a Ti layer thicknesses of 0, 25 nm and 50 nm possess an excellent combination of high effective hardness (> 20 GPa), high plasticity (> 69%), low friction coefficient, and high wear resistance.