摘要
采用盐水浸泡实验研究了铸态(F)、固溶(T4)和250℃下不同时效时间的Mg-10Gd-3Y-0.4Zr镁合金在5%NaCl溶液中的腐蚀行为。结果表明,时效时间为193小时之前,合金的腐蚀速率随时效时间增加而增加,之后有所降低;T4态合金的耐蚀性最好,F态最差.合金腐蚀速率随热处理状态的变化与其微观组织有关,F态合金中的富RE化合物能与基底α相构成电偶腐蚀而加剧合金腐蚀;峰值时效状态下合金中的β′和β1相不能作为腐蚀阻挡层,而过时效状态下连续分布的β相能在一定程度上起腐蚀阻挡层作用,降低合金腐蚀速率.
The corrosion behavior of Mg-10Gd-3Y-0. 4Zr alloy of as-cast （ F）, solution treated （T4） and aged at 250℃ for different time was investigated in 5% NaCl solution by immersion test. The results show that the corrosion rate of the aged alloy increases with aging time untill 193 h and thenceforwards decreases again. The T4 alloy shows the lowest corrosion rate, and the F alloy exhibits the highest corrosion rate. The dependence of the corrosion rate of the alloy on heat treatment can be related to the change of its microstructure. The RE-rich compound in F alloy can induce galvanic corrosion with the adjaeent matrix and thereby accelerate the corrosion process. The precipitation of β＇ and β1 in peak aged condition can not act as a barrier, while the precipitation of coarse β phase in over peak-aged condition can aet as a barrier to some extent and cause a decrease of the corrosion rate.
出处
《腐蚀科学与防护技术》
CAS
CSCD
北大核心
2009年第2期88-90,共3页
Corrosion Science and Protection Technology
