(中国有色金属工业总公司科技部， 北京 100814)
摘 要: 研究了εta=0.8512%总应变幅下7075-RRA铝合金的低周疲劳行为。讨论了应变疲劳位错结构与累积形变之间的关系，进而初步分析了疲劳裂纹的萌生机理，并用循环显微软化/硬化的竞争机制解释了7075-RRA铝合金的宏观循环稳定化行为。
关键字: 铝合金 应变疲劳 位错 裂纹
（Department of Science and Technology Development,
China National Nonferrous Metals Industry Corporation, Beijing 100814）
Abstract:The low-cycle fatigue behavior of 7075-RRA alloy with a total strain amplitude of εta=0.8512% was studied, the relationship between the dislocation substructure of strain fatigue and the accumulated deformation was discussed, consequently the initiation mechanism of fatigue cracks was preliminarily analysed. In addition, the macro cyclic stabilization behavior of 7075-RRA alloy was explained using the cyclic micro softening/hardening competitive mechanism.
Key words: 7075-RRA aluminium alloy strain fatigue dislocation substructure
