(中南大学 机电工程学院 高性能复杂制造国家重点实验室，长沙 410083)
摘 要: 采用拉伸测试、维氏硬度测试和透射电镜分析等方法研究实验应力和时效时间对2524铝合金蠕变时效行为的影响。结果表明：时效时间和试验应力对材料的成形与微观组织均有较大的影响，应力越大、时间越长，蠕变行为越明显；在190 ℃温度下，试验应力为180 MPa，时效时间约为12 h时，材料的硬度和强度趋近于峰值；TEM分析表明，合金板材强度和伸长率的差别主要由时效后强化相S′相和S″相的尺寸和分布密度决定；采用线性回归方法获得合金在190 ℃下稳态蠕变速率与实验应力的本构关系。
关键字: 2524铝合金；蠕变时效成形；力学性能；微观组织；本构关系
（State Key Laboratory of High Performance and Complex Manufacturing,
School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China）
Abstract:The creep age forming effects of 2524 aluminum alloy at different stresses and aging times were investigated through tensile performance, Vickers hardness and TEM. The results show that the aging time and stress have great effect on not only creep behavior but also microstructure of 2524 aluminum alloy. And the creep behavior will become stronger with heavier stress and longer time. The hardness and strength of material will tend to be peak at 190 ℃ when the test-stress reaches 180 MPa and ageing time is 12 h. It can be concluded that the differences of strength and elongation of the alloy plate are determined by the size and distribution of S″ and S′ phase. Finally, the constitutive relationship between the steady creep rate and stress of 2524 aluminum alloy at 190 ℃ is obtained by linear regression.
Key words: 2524 aluminum alloy; creep age-forming; mechanical properties; microstructure; constitutive relationship
