The structure and property of squeeze cast ZA 27 alloy were studied. The porosity defect was remarkablly reduced

the soundness increased

the structure refined and improved and the dendritic segregation reduced for ZA 27 alloy with solidification under pressure so that the ductility increased obviously. The α

β phases decomposition suppression

especially the supersaturated β phase

is the main reason for strength improvement. In addition

α

β phases decomposition also effects on ductility and toughness of this alloy.