(1. 中南大学 材料科学与工程学院,长沙 410083;
2. 湖南泰嘉新材料科技股份有限公司,长沙 410200;
3. 空军航空大学 航空理论系,长春 130022)
摘 要: 通过正交试验获得2519A铝合金优化的二次时效工艺,并通过硬度测试、拉伸测试、极化曲线分析、晶间腐蚀试验和透射电镜观察等方法对比不同时效状态样品的力学性能和耐蚀性能。结果表明:与等温时效相比,二次时效能提高2519A铝合金的屈服强度,同时改善合金的耐蚀性能,这是因为二次时效后晶内形成了细小弥散的θ″相,同时晶内的普遍脱溶使晶内基体与晶界无沉淀析出带(PFZ)的电位差减小。
关键字: 2519A铝合金;二次时效;力学性能;耐蚀性能;无沉淀析出带
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Bichamp Cutting Technology (Hunan) Co., Ltd., Changsha 410200, China;
3. Department of Aviation Theories, Aviation University of Air Force, Changchun 130022, China)
Abstract:An optimized secondary aging process of 2519A aluminum alloy was obtained via orthogonal design. The mechanical properties and corrosion resistance of 2519A aluminum alloy after different aging processes were compared by hardness test, tensile test, polarization curve analysis, intergranular corrosion test and transmission electronic microscopy. The results show that the yield strength of 2519A aluminum alloy increases, and the corrosion resistance of the alloy is improved by secondary aging process, compared with isothermal aging. This is due to the fine and disperse θ″ phase in the grain and the decrease of potential difference between the grain and grain boundary precipitation free zone (PFZ) because of the universal desoluation in the grain after secondary aging.
Key words: 2519A aluminum alloy; secondary aging; mechanical properties; corrosion resistance; precipitation free zone