APPLICATION OF DUPLEX COATINGS FOR METAL INJECTION-MOLDING

Over the past few years the use of titanium nitride and chromium nitride coatings in the field of metal die casting has increased steadily. However, the wear mechanisms of metal die casting, namely heat checking, abrasion and fatigue, cannot be suppressed completely in many applications with a simple hard coating. In this paper we present results obtained with duplex coatings consisting of an in-situ plasma nitriding with high current density plasma beam activation followed by ion plating with titanium or chromium nitride. We show the performance gains that can be achieved over simple coatings in the field of aluminium injection moulding.