铝合金偶接后的大气腐蚀行为
(1. 北京科技大学 材料学院， 北京 100083;
2. 中国科学院 金属研究所 金属腐蚀与防护国家重点实验室，
沈阳 110016;
3. 中国腐蚀与防护学会， 北京 100083)
摘 要: 研究了AM60铸造镁合金与H62铜合金、 LY12铝合金组成的电偶对在北京地区室外曝晒3个月和6个月后的大气电偶腐蚀行为及规律。 结果表明： 镁合金始终是电偶对中的阳极， 当其与H62铜合金和LY12铝合金偶接时， 其腐蚀速率增加1~7倍； 镁合金与H62铜合金偶合后， 其大气电偶腐蚀效应大于其与LY12铝合金组成的电偶对的大气电偶腐蚀效应；在6个月的实验周期内， 随着曝晒时间的延长， 镁合金在北京地区大气环境中的电偶腐蚀效应呈上升趋势； 试样表面润湿时间短是造成AM60镁合金在北京曝晒第一个实验周期(2003.12~2004.2)的电偶腐蚀低于第二个由实验周期(2004.3~2004.5)的主要原因； 北京地区高自然降尘量对镁合金电偶腐蚀将起到加速的作用。
关键字: 镁合金; 铜合金； 铝合金； 电偶腐蚀; 大气腐蚀
magnesium alloy coupled with Cu alloy and
Al alloy
（ 1. College of Materials Science and Engineering,
University of Science and Technology Beijing, Beijing 100083, China;
2. State Key Laboratory for Corrosion and Protection,
Institute of Metal Research, Chinese Academy of Science,
Shenyang 110016, China;
3. Chinese Society of Corrosion and Protection, Beijing 100083, China）
Abstract: The galvanic corrosion behavior laws of AM60 magnesium alloy coupled with H62 brass and LY12 aluminium alloy in Beijing atmospheric environment by exposure for three and six months were investigated respectively. The results show that the magnesium alloys act as anode and their corrosion rates increase by one to seven times when they are coupled with H62 brass and LY12 aluminium alloy. The atmospheric galvanic effect of magnesium alloys coupled with H62 brass is larger than that of the magnesium alloy AM60/ LY12 aluminium alloy. The atmospheric galvanic effect becomes stronger in Beijing with increasing exposure time for the same galvanic couple. For the dry and cold weather of the first test term (Dec, 2003-Feb, 2004), the galvanic corrosion is less than that of the second test term which is of wetness and warmth (March, 2004-May, 2004). The galvanic corrosion of AM60 magnesium alloy is accelerated for the high dust precipitation in Beijing.
Key words: magnesium alloys; Cu alloy; Al alloy; galvanic corrosion; atmospheric corrosion
