The effect of salt fluxing during liquid treatment on the dispersion of the tensile properties of an AlSi9Cu3(Fe) alloy

This study evaluates the impact of melt-cleaning fluxes on the tensile properties of an AlSi9Cu3(Fe) alloy. The melt was stirred using two different salt fluxes and temperatures. Tensile specimens were obtained and tested. Microstructural features and fracture surfaces were analysed. The scattering of the mechanical properties and failure probability were investigated using Weibull statistics. The elongation to fracture was affected by the casting temperature and the flux treatment. The Weibull distributions highlighted the advantages of fluxing on the alloy's ductility. The microstructural investigations support the statistical results. This study confirmed the importance of fluxing and temperature control to improve the melt cleanliness and the reliability of the mechanical properties.