DEVELOPMENT OF OPTIMAL PVD NANO-COMPOSITE COATINGS FOR ALUMINIUM ALLOY DIE CASTING APPLICATIONS

摘要

In aluminium die casting, tools are exposed to erosion, corrosion and soldering due to the frequent contact of the tool surface to casting alloy, to heat checking and gross cracking due to thermal fatigue and to oxidation due to high pouring temperatures. In the present paper a set of CrAlSiN coatings with increasing Al contents were deposited on a typical hot working tool steel to evaluate the influence of the coating composition on the hardness and the specific resistance to cyclic immersion in molten aluminium alloy. In such environment a three times lifetime was achieved if compared with uncoated steel.