Hard-material-coated bodies and method for their production

Abstract

The invention relates to hard-coated bodies with a single- or multi-layer system containing at least one TiAlN hard layer and a method for production thereof. The aim of the invention is to achieve a significantly improved wear resistance and oxidation resistance for such hard-coated bodies. Said hard-coated bodies are characterised in that the bodies are coated with at least one TiAlN hard layer, generated by CVD without plasma stimulation present as a single-phase layer with cubic NaCl structure with a stoichiometric coefficient x>0.75 to x=0.93 and a lattice constant abetween 0.412 nm and 0.405 nm, or as a multi-phase layer, the main phase being TiAlN with a cubic NaCl structure with a stoichiometric coefficient x>0.75 to x=0.93 and a lattice constant abetween 0.412 nm and 0.405 nm, with TiAlN with a wurtzite structure and/or as TiNwith NaCl structure as further phase. Another feature of said hard layer is that the chlorine content is in the range of only 0.05 to 0.9 atom %. The invention further relates to a method for production of the body, characterised in that the body is coated in a reactor at temperatures from 700° C. to 900° C. by means of CVD without plasma stimulation with titanium halides, aluminium halides and reactive nitrogen compounds as precursors, mixed at elevated temperatures. Said coating can be applied to tools made from steel, hard metals, cermets and ceramics, such as drills, millers and indexable inserts.