【摘要】 利用电化学阻抗谱和极化曲线方法 ,研究了模拟酸雨溶液 pH值对LY12铝合金腐蚀行为的影响 .结果表明 ,当模拟酸雨溶液 pH小于 3 1时 ,LY12铝合金的腐蚀电位随pH值的升高而变负 ;当溶液 pH大于 3 4时 ,LY12铝合金的腐蚀电位随 pH值升高而变正 .在 pH小于 3 4的模拟酸雨溶液中 ,LY12铝合金的表面膜发生溶解 ,随着浸泡时间延长 ,膜厚度降低 ,膜阻抗降低 ,LY12铝合金的腐蚀速率升高 .而在 pH大于 3 8溶液中 ,LY12铝合金的表面膜厚度基本不随浸泡时间发生明显变化 ,随浸泡时间增加 ,膜阻抗增大 ,LY12铝合金的腐蚀速率降低 .从铝合金表面膜特性和离子吸附及腐蚀产物等方面 ,对实验结果进行了讨论更多还原

【Abstract】 The effects that pH of simulated acid rain on corrosion behavior of LY12 aluminum alloy was investigated by electrochemical impedance spectrum and polarization curves.It was found that corrosion potential shifts to less noble value with increasing pH at the lower 3.1 and shifts to more noble value at the higher 3.4.In the solutions with pH≤3.4,the surface film of LY12 aluminum alloy was dissolved and the thickness of surface film and film resistance decreased with immersion time,thus corrosion rate of LY12 aluminum alloy increased.In the solutions with pH≥3.8,the film thickness of LY12 aluminum alloy had no apparent change with immersion time,the film resistance increased with immersion time,and thus corrosion rate decreased.The results was discussed from surface film of LY12 aluminum alloy,adsorption of anions and corrosion products.更多还原