7A09铝合金热压缩变形的流变行为及组织演变  

Flow Behavior and Microstructure Evolution of 7A09 Alloy During Hot Compression Deformation

作　　者：马冬威[1] 王敏[1] 胡志华[1] 

机构地区：[1]湖北汽车工业学院材料工程系,湖北十堰442002

出　　处：《热加工工艺》2013年第22期104-107,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(51205116);材料成形与模具技术国家重点实验室开放基金资助项目(2012-P12))

摘　　要：在Gleeble-1500型热模拟试验机上研究7A09铝合金在温度为633～733 K、应变速率为0.01～10.0 s-1、最大变形程度为85%条件下的高温流变行为和微观组织。结果表明7A09铝合金在热压缩变形中的流变应力随变形温度升高而减小,随应变速率增大而增大;该合金的热压缩变形流变应力行为可用双曲正弦形式的本构方程来描述,其变形激活能为123.72 kJ/mol;7A09铝合金中第二相粒子的数量和尺寸,随变形温度升高明显减少;合金动态再结晶程度随应变速率的增大而减小;合金在变形程度70%～85%存在一个临界变形度。指出TiO2纳米管膜晶化的核心工艺参数为晶化处理温度、升降温速率、热处理气氛等,并对今后的研究提出了展望。The flow behavior and deformation microstructure of isothermally compressed 7A09 aluminum alloy in the deformation temperature range from 633 to 733 K, the strain rate range from 0.01 to 10.0 s-1 and the maximum deformation of 85% were investigated on a Gleeble-1500 isothermal compressor. The results show that the flow stress decreases with increasing deforming temperature and increases with increasing strain rate. The flow stress of the alloy during hot compression deformation can be described by constitutive equation in hyperbolic sine function with a hot deformation activation energy of 123.72 kJ/mol. The volume and size of the second phases decrease obviously with increasing temperature. The extent of the recrystallization of the alloy decreases with increasing strain rate. 7A09 aluminum alloy has a threshold deformation in 70%- 85% deformation.

关 键 词：7A09铝合金 热压缩变形 流变应力 微观组织 

分 类 号：TG164.2[金属学及工艺—热处理]