Effects of Sb Addition on Microstructure and Mechanical Properties of Heat-Treated Recycled Al-Si-Mg Alloy

The uses of cast aluminum alloys in automotive and aerospace applications are growing rapidly because of the need to reduce weight and improve the efficiency of the engine as whole. The service life of aluminum cast component is determined by the size, form and distribution of microstructural features throughout the casting, especially in those regions that are critically stressed. The effects of antimony (Sb) additions on the microstructure and mechanical properties of recycled heat-treated Al−10.55Si-4.95Mg alloy were investigated. The results show that Sb can effectively modify the eutectic silicon platelets depending on its geometry. However, modification in the eutectic Si platelets were observed with increase addition of Sb. Improved mechanical properties in the as-cast Al-alloy on tensile strength (121 N/mm2) and yield strength (91.25 N/mm2) were obtained at 7.50 wt. % Sb addition.