ABSTRACT

The effect of rare earth elements Ce and Y addition on microstructure and corrosion behaviour of an extruded ZK60 magnesium alloy was investigated. Materials characterisation was performed using a scanning electron microscope and X-ray diffraction. Corrosion behaviour of ZK60 and ZK60-3x (x = Ce, Y) alloys were evaluated using electrochemical impedance spectroscopy and potentiodynamic polarisation test. At the end of evaluations, the best corrosion performance was observed for the ZK60 base alloy, due to its microstructure consisting of larger grains and lower volume fraction of second phase particles. On the other hand, the two other alloys suffered from galvanic corrosion rising from their RE-containing particles and the more fraction of high energy grain boundaries acting as possible areas for corrosion initiation.

摘要

研究了稀土元素 Ce 和 Y 添加对挤压 ZK60 镁合金显微组织和腐蚀行为的影响。使用扫描电子显微镜和 X 射线衍射进行材料表征。ZK60 和 ZK60-3 的腐蚀行为x ( x = Ce, Y) 合金使用电化学阻抗谱和动电位极化测试进行评估。在评估结束时，观察到 ZK60 基合金的最佳腐蚀性能，因为它的微观结构由较大的晶粒和较低的第二相颗粒体积分数组成。另一方面，另外两种合金由于其含稀土颗粒而遭受电偶腐蚀，并且更多部分的高能晶界作为可能的腐蚀起始区域。