Corrosion resistance in molten aluminium environment of tool steels for pressure die casting

The corrosion resistance of tool steels used for pressure die casting in molten aluminum environment was investigated. Steel AISI H13, steel for combustion valves and raging steel without coating, with TiAlN coating applied by PVD process and with a semi permanent coating named Protalcar were used for the study. The experiment was conducted under conditions of continuous contact between the die and molten alloy to simulate the corrosion behaviour. Corrosion resistance in static immersion was evaluated as a reduction of the external surface plunged in molten aluminum. Results depicted that the H13 steel showed a better compromise between hardness at high temperature and corrosion resistance in molten aluminum.