Influence of injection temperature and pressure on the microstructure, mechanical and corrosion properties of a AlSiCu alloy processed by HPDC

Highlights: • Injection temperature and pressure influence the microstructure and porosity in cast parts. • Mechanical properties showed a complex dependence with porosity and microstructure. • Corrosion performance scaled up with casting porosity. - Abstract: Processing parameters affect the overall performance of parts obtained by high pressure die casting (HPDC). The aim of the present work was to investigate the effect of injection temperature and pressure on the microstructure, tensile properties and corrosion behavior of the hypoeutectic AlSi₉Cu₃(Fe) alloy (EN AC 46000). The porosity level of the castings was also evaluated. The microstructure of the as-cast samples consisted of α-Al grains, interdendritic Al–Si phase and complex intermetallics. The microstructural features were slightly affected by different combinations of temperature and pressure. The porosity fraction increased with temperature at 70 MPa. Tensile properties were improved for the samples obtained at 709 °C and 70 MPa. The corrosion resistance scaled up with the porosity level of the samples but no obvious relationship could be established between microstructure and this property.