Strengthening and toughening mechanism of ZA27 squeeze-cast alloy

摘要

The strengthening and toughening mechanisms of ZA27 squeeze-cast alloys were investigated in the present work. Results show that improvement of mechanical properties was not, as generally believed, resulted from grain refinement, but mainly fromsuppression of theα andβ phase's decomposition, especially from supersaturation hardening of theβ phase. Regarding the toughening of ZA alloys, it is pointed out that excellent elongation is a combined contribution of high soundness, fine grain sizeand little dendritic segregation in ZA27 squeeze-cast alloys.