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 adjacent 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 act as a barrier to some extent and cause a decrease of the corrosion rate.
