Enhancing ambient and elevated temperature performance of hypoeutectic Al–Ce cast alloys by Al3(Sc,Zr) precipitate

This study explored the consequences of incorporating Sc and Zr into hypoeutectic Al-9Ce cast alloys, specifically investigating their influence on microstructure and mechanical properties. The findings demonstrate the significant reduction in the grain size of the Al-9Ce alloy while successfully maintaining the distinctive shape of the eutectic Al₁₁Ce₃ phase through the incorporation of Sc and Zr additions. During aging treatments, Al₃(Sc,Zr) coherent precipitates formed both at the interface between the α-Al and Al₁₁Ce₃ phases and within the α-Al matrix. Remarkably, this leads to optimal hardness achieved within a short duration of 3 hours at 350 °C. Peak-aged quaternary Al-9Ce-xSc-yZr alloys show significantly better tensile strength than the binary Al-Ce alloy in both ambient and elevated temperatures. Overall, the study underscores promising prospects of Al-Ce-Sc-Zr alloys for use in high-temperature applications, as they exhibit enhanced mechanical properties.