挤压铸造ZA27合金的凝固特性及组织分析

The Solidification Characteristic and Structure Analysis of ZA27 Alloy Squeeze Casting

研究了ZA27合金挤压铸造的凝固特性和组织。差热分析表明挤压铸造可以使锌铝合金的凝固过程发生变化,压力在750MPa以上可抑制共晶反应的发生。压力下凝固,可大大减少ZA27合金的缩孔、缩松、气孔等缺陷,提高合金致密度,细化和改善组织,减轻枝晶偏析,使铸件整体的成分均匀。

The solidification characteristic and structure of squeeze casting ZA27 alloy were studied. Differential thermal analysis shows that squeeze casting can bring change to the solidifying process of ZA27 alloy. Pressure restrains the occurrence of eutectic reaction above the pressure of 750MPa.The shrinkage cavity, shrinkage porosity, pore and so on were remarkably reduced, the soundness increased, the structure refined and improved and the dendritic segregation reduced for ZA27 alloy with solidification under pressure so that the integral ingredient uniformed.