(1. 内蒙古工业大学 材料科学与工程学院，呼和浩特市 010051；
2. 北京有色金属研究总院，北京 100088)
摘 要: 采用Gleeble1500D热力模拟机按设计的轧制工艺对7055合金进行压缩试验以模拟企业多道次热轧过程，获得多道次压缩的流变应力曲线。对经不同道次压缩水冷试样进行硬度测试、金相显微镜透射电镜和EBSD分析，研究其流变应力、硬度和显微组织特征。结果表明：热压缩时，每道次的峰值应力并未随Z值的增加而显著增加，总应变小于0.303时，峰值应力随应变增加而增大；应变从0.303到1.148，峰值应力基本保持不变，应变从1.148到1.609，峰值应力再次增加；经不同道次热压缩水冷试样的硬度随压缩道次的增加，硬度先增加后减小；由于热轧过程中的动态行为和静态行为的交互作用，形成大量再结晶晶粒。
关键字: Al-Zn-Mg-Cu-Zr合金；再结晶；流变应力；第二相
（1. School of Materials Science and Engineering, Innermongolia University of Technology, Huhhot 010051, China;
2. General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:The hot compression tests of 7055 aluminum alloy were carried out on Gleeble1500D thermal-mechanical simulator according to designed rolling processes to simulate the multi-pass hot rolling process. The flow stress curve was obtained. The features about flow stress, hardness and microstructure of the samples deformed to various strain accompanied with water quenching were investigated through hardness testing and OM, TEM and EBSD analysis. The results show that the peak stress doesn’t significantly increase with increasing the Z value. The peak stress increases when the strain is less than 0.303, while the peak stress keeps basically constant when the strain ranges in 0.303−1.148. The hardness firstly increases and then decreases with increasing the compression pass number. A lot of recrystallization grains are formed due to counterchanging roles of the dynamic behavior and static behavior.
Key words: Al-Zn-Mg-Cu-Zr alloy; recrystallization; flow stress; second phase
