Epitaxial growth of a TiN layer by the implantation of Ti+ ions into Mo in a nitrogen atmosphere and the effect of post-implantation irradiation-induced heat treatment on the structure of the coating-substrate transition layer

The ion implantation of Ti + in a nitrogen atmosphere at P N =0.13 Pa produces a TiN layer of about 200 nm thick on the surface of a Mo substrate. The mechanism responsible for the growth of the coating was investigated in detail by electron microscopy, X-ray diffraction, and Auger electron spectroscopy. Owing to the epitaxial growth of an fcc TiN layer, with the grains having predominantly a (001) orientation parallel to the substrate plane, a diffuse transition zone with a metastable hcp phase, which provides a proper match between the matrix and coating lattices, is formed on the bcc molybdenum substrate. The surface fcc TiN layer has no texture. Post-implantation irradiation-induced heat treatment brings about phase recrystallization of the structure at the coating-substrate interface, predominantly due to a rearrangement of the textureless TiN layer and the disappearance of the hcp phase from the transition layer