Processing of P/M T15 high speed steels by mould casting using thermosetting binders

In this work we present the application to a T15 high speed steel of a modified metal injection moulding process based on the use of a thermosetting resin. This method has been successfully applied to produce 316L stainless steels and M2 HSS. The main characteristic of this manufacturing method is that the slurry (polymer and metal powder) is introduced into the mould at room temperature and afterward is heated at 90°C in order to polymerise the resin. We have optimised the powder-binder formulation and the best thermal debinding cycle by means of thermogravimetric analysis. Since the microstructure and properties of the HSS is very sensitive to the sintering temperature, its effect on the density, hardness, transverse rupture strength and microstructure was investigated. The mechanical properties obtained are in good agreement with other HSS parts manufactured by conventional MIM. During the sintering process it has been identified vanadium carbide (MC) and tungsten carbide (M6C) that are homogeneously distributed on the steel matrix.