合金化对汽车轮毂用镁合金耐蚀性的影响分析

Analysis on Effects of Alloying on Magnesium Alloy Corrosion Resistance for Automobile Hub

在汽车轮毂用AZ31镁合金中添加了不同含量的合金化元素Cr、V和Sr,并进行了中性盐雾腐蚀、酸雨全浸腐蚀和电化学腐蚀试验。结果表明:合金化元素Cr、V和Sr的添加,可改善汽车轮毂用AZ31镁合金的耐蚀性,且Sr的改善效果最好,其次是Cr和V;与未添加合金化元素相比,分别添加合金化元素Cr、V和Sr,可使合金在240 h中性盐雾腐蚀后的质量损失率分别减少14.7%、12.9%和16.0%;在240 h酸雨全浸腐蚀后的质量损失率分别减少16.5%、13.6%和17.8%;腐蚀电位分别正移284、255和341 m V。

Adding different content of alloying elements Cr, V and Sr into AZ31 alloy for automotive wheel hub, and the neutral salt spray corrosion, acid rain immersion corrosion and electrochemical corrosion test for AZ31 alloy was carried out. The results show that adding alloying elements Cr, V and Sr can improve the corrosion resistance of AZ31 alloy automobile hubs, and the improvement effect of Sr is best, followed by Cr and V; compared with that without adding alloying elements, AZ31 alloy with adding alloying elements Cr, V and Sr, respectively can make alloy mass loss rate after 240 h neutral salt spray corrosion decrease by 14.7%, 12.9 % and 16.0%, respectively. The mass loss rate after 240 h acid rain immersion corrosion decreases by 16.5%, 13.6% and 17.8%. The corrosion potentials are positive shift for 284 mV, 255 mV and 341 mV, respectively.