Cu/Mg含量对2024铝合金耐蚀性能的影响  

Effect of Cu/Mg content on corrosion resistance of 2024 aluminum alloy

作　　者：吴学昆 罗兵辉[1] 柏振海[1] 邓攀 莫文锋 WU Xuekun;LUO Binghui;BAI Zhenhai;DENG Pan;MO Wenfeng(School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《有色金属材料与工程》2022年第6期1-7,共7页Nonferrous Metal Materials and Engineering

基　　金：军工配套项目(412100008)。

摘　　要：Cu元素和Mg元素是2024铝合金中的主要添加元素,这两种元素的含量对合金的性能有至关重要的影响。针对Cu/Mg的质量比分别为3.49,2.38和2.19的三种合金,利用极化曲线、电化学阻抗谱、晶间腐蚀、表面粗糙度测试以及光学显微镜、扫描电子显微镜观察等手段研究Cu/Mg的质量比对2024铝合金耐腐蚀性和化学铣切表面粗糙度的影响。研究结果表明:腐蚀电流对2024铝合金的耐蚀性影响要大于腐蚀电势;随着Cu/Mg的质量比的增加,合金氧化膜厚度增加;当Cu/Mg为2.38时,合金的电化学腐蚀速率为24.3μm/a,电荷转移电阻为23662Ω/cm^(2),晶间腐蚀深度为134.3μm,化学铣切表面粗糙度为0.753μm,此时综合性能最好。Cu and Mg are the main added elements in 2024 aluminum alloy,and the content of these two elements has a crucial influence on the properties of the alloy.In this work,three alloys with Cu/Mg of 3.49,2.38 and 2.19 were fabricated.For the three alloys with Cu/Mg mass ratios of 3.49,2.38 and 2.19,respectively,the effects of Cu/Mg mass ratios on the corrosion resistance and surface roughness of 2024 aluminum alloy were studied by means of polarization curve,electrochemical impedance spectroscopy,intergranular corrosion,surface roughness test,optical microscope and scanning electron microscope observation.The results show that the effect of corrosion current on the corrosion resistance of 2024 aluminum alloy is greater than that of corrosion potential.With the increase of Cu/Mg,the oxide film thickness of the alloy is increased.When Cu/Mg mass ratios is 2.38,the electrochemical corrosion rate of the alloy is 24.3μm/a,charge transfer resistance is 23662Ω/cm^(2),intergranular corrosion depth is 134.3μm,the surface roughness of chemical milling is 0.753μm,and the overall performance is the best at this time.

关 键 词：2024铝合金 电化学阻抗谱 腐蚀性能 化学铣切 表面粗糙度 

分 类 号：TG146.21[一般工业技术—材料科学与工程]