高强铝合金加速腐蚀方法的研究

STUDY OF THE ACCELERATED CRROSION TESTS OF HIGH-STRENGTH ALUMINUM ALLOYS

以 p H=3 .0的 5%Na Cl+0 .5%( NH4) 2 SO4的溶液 (用醋酸调整 p H值 )为加速剂 ,对 LY1 2和 LC4两种高强铝合金进行了间歇盐雾和周期轮浸腐蚀试验。结果表明 :两种加速腐蚀方法之间有类似的腐蚀动力学规律 ,其中间歇盐雾试验相对于大气腐蚀有较好的模拟性和加速性。根据材料的腐蚀动力学规律提出了“参照腐蚀率”,的概念 ,并以其作为腐蚀程度的评估准则 ,定量评定了间歇盐雾相对于大气腐蚀的加速性。

With the solution of 5%NaCl+0.5%(NH 4) 2SO 4(pH=3.0), 2024 and 7075 aluminium alloys were tested in a salt spray cabinet(one hour wet, one hour dry) and a periodical immersion cabinet respectively. The results obtained from the two tests showed similar corrosion kinetic laws. The simulation and acceleration of the salt spray test were better than those of the periodical immersion test. Based on the corrosion kinetic law obtained, a concept of \!Reference Corrosion Rate\' was proposed, which can be used to evaluate the corrosion extent and to estimate the time equivalence between the salt spray test and the atmospheric corrosion.