Effect of tin addition on inhibition of cast cracking in Mg-Al-Ca alloys

Abstract

In a previous study, we reported that adding tin to Mg-Al-Ca alloys inhibits cast cracking while maintaining excellent heat resistance. In this study, to clarify the mechanism resulting in the improved castability, Mg-Al-Ca alloys with different compositions were cast by high-pressure die casting into an I-shaped die with strain gauge instrumentation. The solidification shrinkage and thermal contraction of the alloys during the solidification and cooling process were investigated. The addition of tin decreased the solidification shrinkage of the alloys, and the tensile stress in the alloys was relaxed. On the basis of these results, the addition of tin is considered to improve the castability.