Abstract Microstructural characteristics and corrosion behavior of extruded Mg-1Bi-1Al-xCa (x = 0, 0.6 and 1.2 wt%) alloys were investigated. It was found that the average grain size, texture intensity and corrosion resistance of the present low-alloyed alloy system initially increased and then decreased with increasing Ca content. Intergranular corrosion was observed in the present alloy system, which was related to the higher energy of the grain boundaries. Furthermore, the corrosion mode changed from pitting corrosion in the Ca-free alloy to the mixed pitting and filiform corrosion in the Ca-containing alloys in the initial stage of immersion based on the analysis in terms of micro-galvanic corrosion and the formation of protective film. As the immersion time increased, the filiform corrosion dominated in the Mg-1Bi-1Al-0.6Ca alloy. However, the corrosion product film of the Mg-1Bi-1Al-1.2Ca alloy was quickly destroyed due to the shedding of the coarse Mg2Bi2Ca2 phase, which resulted in severe corrosion.

中文翻译：

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合金化钙对挤压镁-铋-铝基合金组织和腐蚀行为的影响

摘要 研究了挤压成型的 Mg-1Bi-1Al-xCa (x = 0, 0.6 和 1.2 wt%) 合金的显微组织特征和腐蚀行为。发现本低合金合金体系的平均晶粒尺寸、织构强度和耐腐蚀性能随着Ca含量的增加先增大后减小。在本合金体系中观察到晶间腐蚀，这与较高的晶界能量有关。此外，基于微电偶腐蚀和保护层形成的分析，腐蚀模式从无钙合金的点蚀转变为含钙合金在浸泡初期的混合点蚀和丝状腐蚀。电影。随着浸泡时间的增加，丝状腐蚀在 Mg-1Bi-1Al-0.6Ca 合金中占主导地位。然而，