1990 Volume 40 Issue 3 Pages 188-194
In Al-Si-Cu alloy castings, the eutectic melting heat treatment promoted spheroidization of eutectic Si and increased the impact strength. In this study, this treatment was applied to Al-Si-Cu alloy castings modified with Sr. The impact strength of high purity alloy castings increased by Sr-and Na-modification. The strength of modified alloy castings was slightly improved by this heat treatment. On the other hand, the strength of production purity alloy castings increased by only Sr-modification, and was significantly improved by eutectic melting heat treatment. The impact strength of production purity alloy castings was dependent on the shape and size of both eutectic Si phase and Fe bearing compounds which were changed by Sr-or Na-modification and solution heat treatment.
