模拟舰载环境对2124铝合金耐蚀及疲劳性能的影响

 采用酸性盐雾试验模拟舰载环境，研究了舰载环境对典型航空铝合金2124铬酸阳极氧化、硼硫酸阳极氧化和苹果酸硫酸阳极氧化耐蚀和疲劳性能的影响，采用电化学阻抗谱（EIS）分析了膜层结构的变化规律，采用轴向疲劳检测不同腐蚀时间后的疲劳寿命，并对疲劳断口进行分析。结果显示，阳极氧化处理能够有效提高其耐蚀性能，铬酸阳极氧化试样经过4个循环酸性盐雾后出现腐蚀，硼硫酸阳极氧化和苹果酸硫酸阳极氧化从第6周期开始出现腐蚀；阳极氧化试样的疲劳寿命随酸性盐雾循环次数而衰减，衰减趋势与出现腐蚀的规律相吻合；苹果酸硫酸阳极氧化试样的疲劳寿命衰减最为缓慢。

Effect of shipborne environment on corrosion resistance and fatigue property of 2124 aluminum alloy

Shipborne environment is the main service circumstance of aircraft equipment in the future, which combines features of high temperature, high relative humidity, high salinity from marine environment and acidic gas from shipborne equipment. Aluminum alloys suffer severe corrosion in such an environment. In this study acidic salt spray test is used to simulate the shipborne environment and applied to 2124 aluminum alloys with three different anodic oxidations, i.e., chromic acid anodization (CAA), boric-sulfuric acid anodization (BSAA) and malic-sulfuric acid anodization (MSAA). The corrosion resistance and fatigue property of anodized 2124 alloys are evaluated at different cycles of the test. The structure evolution of anode oxide films is characterized by electrochemical impedance spectroscopy(EIS). The axial fatigue life of anodized samples is measured after different cycles of the test. The fracture morphology is also studied. The results suggests that anodic oxidation can significantly enhance the corrosion resistance of 2124 alloy. BSAA and MSAA samples exhibit better corrosion resistance than CAA samples. Corrosion signs of the substrate of CAA appear after 4 cycles of the test, while after 6 cycles for BSAA and MSAA. The fatigue life generally declines with salt spray test cycles, which is consistent with the corrosion resistance performance. However, MSAA has the highest residual fatigue life.