Effect of Casting Microstructure on the Mechanical Performance of Recycled EN AC-43200 Al-Si Alloy

This work investigates the influence of casting microstructure on the mechanical performance of ad hoc samples of recycled EN AC-43200 Al-Si alloy. Three batches are produced by modifying the casting process parameters (i.e., molten alloy temperature and in-mold cooling conditions) to obtain different casting microstructures. Room temperature tensile and high-cycle fatigue tests, coupled with metallography, X-ray tomography, and fatigue fracture surface analysis, are performed to elucidate the relationship between microstructural characteristics and mechanical properties of the investigated alloy. The findings indicate that casting pores and intermetallic precipitates play a pivotal role in influencing the mechanical behavior and performance of cast, recycled EN AC-43200 Al-Si alloy. Additionally, an inverse correlation between secondary dendrite arm spacing (SDAS) and both tensile properties and fatigue life is established.