PetroMat

Sintered components are gaining more and more applications, their success towards the most traditional technologies is due to the possibility of low cost manufacturing of parts having complicated shape coupled with restricted tolerances, to the very high yield of the utilisation (>95 %) of the raw material, as well as to the availability of a large choice of powders with a wide range of chemical composition.

In the present work reactive powders, mixed to stainless steel ones, have been used to increase the density of sintered parts, through the generation of a liquid phase. High density is connected to porosity decrease and also to transformation from open to close pores: this increases also the corrosion behaviour and the mechanical properties.

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.