【作者】 张大辉； 李志强； 钟雪友；

【Author】 Zhang Dahui Li Zhiqiang Zhong Xueyou (BAMTRI, 100024 University of Science and Technology Beijing, 100083)

【机构】 北京航空制造工程研究所； 北京科技大学；

【摘要】 采用Gleeble1500热模拟机、光学显微镜以及图象分析仪等设备,通过量化对比触变压缩前后的显微组织特征,系统研究了平行板压缩条件下,半固态Alsi7Mg合金在触变压缩过程中的变形机制。试验结果表明,触变压缩过程中,合金的变形机制包括液相流动、液相阻尼流动、颗粒滑动以及颗粒塑性变形等四种变形机制.固相分数和变形速率是影响变形机制变化的两大要素。在液固两相区间,随着固相分数和变形速率的提高,触变压缩过程中合金主导变形机制将由液相阻尼流动和液相流动逐渐转变为颗粒塑性变形和颗粒滑动。更多还原

【Abstract】 The deformation mechanisms of semi-solid AlSi7Mg alloys had been investigated systematically, using Gleeble-1500 thermal simulator,optical microscopy, image analysis instrument and other related equipments. Results indicate that the semi-solid deformation behaviors can be described by four mechanisms: Liquid Flow(LF),Flow of Liquid incorporating Solid Particles(FLS),Sliding between Solid Particles(SS),and Plastic Deformation of Solid Particles(PDS) mechanisms. During semi-solid deformation, the solid fraction and the deformation rate are two key factors to affect the transformation of the deformation mechanism. As they increase, the deformation mechanism changes from LF and FLS to SS and PDS.更多还原