关键词: 铝锂合金, 酸性盐雾, 阳极氧化, 耐蚀性能, 抗拉强度

Abstract: Effect of anodizing process on the corrosion behavior and tensile strength of Al-Li alloy which exposed to acid salt spray environment was studied by means of surface morphology observation, corrosion rate analysis and room temperature tensile test. The results show that in acid salt spray environment, the unanodized Al-Li alloy occurs significant corrosion after 24 h with a corrosion area of 58.417%. After 144 h, the corrosion morphology is more uniform with a corrosion area of 88.350%. The corrosion mass gain rate decreases significantly with the extension of salt spray corrosion time. The tensile strength of the unanodized Al-Li alloy under different corrosion time is about 400 MPa. The corrosion of the sulfuric acid anodized and boron sulfuric acid anodized Al-Li alloy needs more time and the corrosion rate is slower. In acid salt spray environment, no obvious corrosion is found after 240 h, and the corrosion area is only about 7% after 360 h. The tensile strength of the Al-Li alloy under different corrosion time is about 500 MPa. After anodizing, an oxide film forms on the surface of the Al-Li alloy, which blocks the etching of Cl^- in corrosion solution, and significantly improves the corrosion resistance and the tensile strength of the Al-Li alloy in the acid salt spray environment.

Key words: Al-Li alloy, acid salt spray, anodizing, corrosion resistance, tensile strength