半固态A356合金的压缩变形行为  

Deformation Behavior of Semi-solid A356 Alloy

作　　者：王平[1] 董维国[2] 路贵民[1] 崔建忠[1] 

机构地区：[1]东北大学材料电磁过程研究教育部重点实验室,辽宁沈阳110004 [2]中华人民共和国教育部科技司,北京100816

出　　处：《东北大学学报（自然科学版）》2003年第6期586-588,共3页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(59974009);国家高技术研究发展计划项目(2002AA337010);第29批中国博士后科学基金资助项目

摘　　要：采用Gleeble 1500热模拟试验机,对半固态铸造铝合金A356进行了半固态压缩和固态压缩实验,分析了它们的应力 应变关系·结果表明:在变形速率小于5s-1的中、低变形速率下压缩,随着变形速率的升高,流动应力增加;在变形速率大于5s-1的高变形速率下压缩,流动应力下降:随变形程度的增加,半固态压缩发生应变 软化现象;分析了半固态压缩变形过程中的几种变形机制,讨论了半固态触变过程中的金属流动特点,为半固态成形的模具设计提供理论依据·Unilateral compression tests on A356 alloy of semi-solid and solid were carried out using the Gleeble-1500 dynamic material testing machine. The relationship between the stress and strain for the semi-solid A356 alloy was established in different deformation conditions. The results show that the flow stress increase s with increasing strain rate when  is lower than 5?s-1. How ever, the stress decreases with increasing strain rate when  is hig her than 5?s-1. It decreases also with increasing the strain, that is to say, the strain softening occurs during semi-solid deformation. At last, by ana lyzing several deformation mechanisms and by discussing metal flowing characteri stic during thixoforming of semi-solid, several rules are suggested for the die design in semi-solid forming.

关 键 词：A356合金 半固态 压缩变形 变形速率 机理 金属流动 模具设计 

分 类 号：TG146.3[一般工业技术—材料科学与工程]