铝合金设备深海应力腐蚀有限元模拟研究

Finite Element Simulation Study on Deep-sea Stress Corrosion of Aluminum Alloy Equipment

摘要:

深海开发具有极高的经济战略意义，而深海高压、高盐度的极端环境中极易引起金属设备的应力腐蚀问题。以揭示 2 种铝合金材料设备在深海环境中的力学载荷与腐蚀之间的关系以及具体的腐蚀机理为目标，使用实验测试配合有限元计算的方法对设备模型中不同材质的各个部位分别进行了固体力学及电化学腐蚀耦合的数值模拟仿真分析。计算结果表明在0.5 km深度海域中，7049铝合金材质设备表面最大腐蚀速率仅为0.013 mm/a，这一数值略低于6A02铝合金材质设备表面0.016 mm/a的最大腐蚀速率，证明7049铝合金材料更适应深海服役环境。

Abstract:

Deep-sea development holds significant economic and strategic value. However，the extreme conditions of high pressure and high salinity in deep-sea environments often lead to stress corrosion issues in metal equipment. This project aims to elucidate the relationship between mechanical loads and corrosion in two types of aluminum alloy materials used in deep-sea equipment，as well as the specific mechanisms of corrosion. Numerical simulation analysis of solid mechanics and electrochemical corrosion coupling for various parts of the equipment model made from different materials is carried out through experimental test and finite element analysis（FEA）. The calculation results indicate that，at a depth of 0.5 km，the maximum corrosion rate on the surface of equipment made from 7049 aluminum alloy is only 0.013 mm per year，which is slightly lower than the maximum corrosion rate of 0.016 mm per year observed on the surface of equipment made from 6A02 aluminum alloy. This demonstrates that 7049 aluminum alloy is more suitable for service in deep-sea environments.