WEAR MECHANISMS OF (TI1-XALX)N COATINGS IN DRY DRILLING

Increasing environmental pollution and problems concerning waste dispo sal demand the development of ecological manufacturing technologies. T oday's research activities are concentrated on improving the propertie s of cutting tools for dry machining by optimizing manufacturing techn ologies and tool geometries, by alloying of special cutting materials and by coating of tools. In dry drilling of tempered steel, the wear m echanisms of different PVD-coated WC-cemented carbide tools were inves tigated. Considered topics are the influence of the used sputter techn ology (magnetron sputter ionplating-high ion sputtering) and of the Al /Ti-ratio on structure, adhesion strength and microhardness of (Ti,Al) N coatings and the effects on wear behaviour. Due to increased interfa ce strength of microblasted tools with (Ti,Al)N-layers of high alumini um content, a superior wear behaviour in dry machining was found. (C) 1997 Elsevier Science S.A.