(1. 重庆大学 材料科学与工程学院，重庆 400044；
2. 重庆西彭产业工业园区，重庆 401326)
摘 要: 通过Gleeble-3500热模拟机在350~500？℃温度范围对2195铝锂合金进行平面应变压缩实验，应变速率为0.01~1？s-1，变形量60%。研究合金在高温下的流变行为并通过背散射电子衍射(EBSD)和X射线衍射(XRD)揭示了微观组织的演变规律。结果表明：流变应力随应变速率的增加而升高，而随着温度的升高流变应力降低，并且达到峰值应力和稳态流变时所需的应变也减少，建立含有双曲正弦关系的本构方程并得到合金的变形激活能Q为278.208？kJ/mol；随着Zener-Hollomon参数值的增加，合金的流变集中增加，合金的软化机制主要是动态回复，此外还有动态再结晶形成，动态再结晶主要为不连续动态再结晶，而连续动态再结晶和几何动态再结晶均容易在较低Z值和较高Z值下形成；变形组织中含有大量的轧制织构，变形晶粒主要为S{123} 、Brass{011} 、Copper{112} 和Goss{011} 这4种取向。
关键字: 2195铝锂合金；平面应变压缩；流变行为；微观组织
（1. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China;
2. Chongqing Xipeng Industrial Park, Chongqing 401326, China）
Abstract:Plane strain compression tests of AA2195 aluminum alloy were conducted on Gleeble-3500 system in the temperature range from 350 ℃ to 500 ℃ and at strain rate range from 0.01？s-1 to 1？s-1 with 60% thickness reduction. The flow behavior was studied in present work and the microstructure was revealed by electron backscatter diffractometry(EBSD) and X-ray diffractometry(XRD). The results show that the stress increases with the increase of strain rate whereas decreases with the increase of temperature, the peak strain and the critical strain for attaining steady state decreases with increasing temperature. A constitutive equation based on the hyperbolic sine equation is established with the deformation activation energy is calculated to be 278.208 kJ/mol. Flow localization increases with the increase of the value of Zener-Hollomon parameter, the basic softening mechanism is dynamic recovery(DRV), besides, dynamic recrystallization(DRX) occurs and is mainly discontinuous recrystallization(DDRX), continuous recrystallization(CDRX) and geometric recrystallization(GDRX) occurs more easily in lower Z value and higher Z value, respectively. Significant amounts of the major rolling texture components, namely, S{123} , Brass{011} , Copper{112} and Goss{011} are observed at deformed samples.
Key words: 2195 Al-Li alloy; plane strain compression; flow behavior; microstructure
