OBSERVATIONS ON THE STRUCTURE, HARDNESS AND ADHESION PROPERTIES OF A SELECTION OF MULTICOMPONENT REFRACTORY ELEMENT NITRIDE COATINGS

In recent years, the introduction of titanium-based nitride and carbid e coatings has led to a marked improvement in the tribological behavio ur and service life of many engineering components such as cutting too ls and metal forming dies. Although TiN performs satisfactorily, incre asing demands from manufacturing industries have driven the developmen t of thin coatings to optimised performance. Coatings are being sought with, inter alia, improved hardness and wear resistance. In this cont ext, attention has been focussed on a number of advanced multi-compone nt nitride coating systems based on, or incorporating, refractory elem ent additions. Thus the use and incorporation of refractory and semi-r efractory elements such as Al, Zr, Cr or V promises to provide coating s with higher hardness and improved wear resistance due to the formati on of novel complex structures. In the present investigation, a wide s election of single and multi-component coatings (TiN, CrN, ZrN, TiAlN, TiAlVN, TiCrN, TiZrN and TiCN) have been deposited onto high speed st eel substrates, using the technique of unbalanced magnetron sputtering . This paper presents data on the structure, hardness and adhesion pro perties of these coatings. The implication of these results is then di scussed.