(1. 中南大学 材料科学与工程学院，长沙 410083；
2. 中南大学 有色金属材料科学与工程教育部重点实验室，长沙 410012)
摘 要: 采用透射电镜、拉伸试验、剥落腐蚀试验等手段，研究7055铝合金在回归时效阶段的晶界η相形貌、尺寸、间距及其粗化动力学行为，以及对最终材料性能的影响。结果表明：随着回归温度的升高或回归时间的延长，晶界η相不断粗化，间距也不断增大；且回归温度越高，晶界η相粗化速率越快。在本实验条件下，该合金晶界η相的粗化激活能Q=1.13 eV，据此建立晶界相粗化动力学模型。
关键字: 7055铝合金；回归时效；晶界析出相；粗化动力学
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410012, China）
Abstract:The morphology and coarsening kinetics of grain boundary precipitates (η) in the regression aging stage of 7055 aluminium alloys were studied by transmission electron microscopy (TEM), and the corresponding effects on the mechanical property and corrosion resistance were measured by tensile tests and exfoliation corrosion tests. The results show that the grain boundary precipitates (η) are coarsened and the inter-space increases with the retrogression temperature or retrogression time increasing. The coarsening rate of η precipitates increases with retrogression temperature increasing. The coarsening activation energy is 1.13 eV, and a modified coarsening kinetics model of grain boundary precipitates was proposed.
Key words: 7055 aluminium alloy; regression aging; grain boundary precipitates; coarsening kinetics
