半固态ZA27合金挤压成形的试验研究

Extrusion Forming for the Semi-solid ZA27 Alloys

分别对常规ZA2 7合金和经机械搅拌得到的半固态ZA2 7合金在不同的温度下进行二次重熔挤压成形试验 ;并对ZA2 7合金在二次重熔后的金相组织与挤压成形得到的金相组织进行了分析。结果表明 ,半固态ZA2 7合金在 3 90～ 415℃下二次重熔 ,组织中蔷薇状α Al分离球化 ,晶粒更加细化 ,近球形的α相长大 ,边缘更加光滑 ,此时进行挤压成形挤压应力较小 。

The extrusion forming at different temperature was conducted for conventional ZA27 alloy and semi solid ZA27 alloy made by mechanical stirring. The original and water quenched microstructure of both billet reheated at 420 ℃,holding time 10 min were compared and analyzed.The results showed that the rose like α Al phase for semi solid extrusion formed billet reheated at 390～415 ℃ by extrusion forming was sphered and refined.As a results,due to smaller extrusion forming,both structure and apperance of the extruded piece were quit well satisfied.