(1. 中南大学 粉末冶金国家重点实验室，长沙 410083；
2. 中南大学 湘雅医院，长沙 410008；
3. 中南大学 湘雅医学院，长沙 410013)
摘 要: 以Zn与Ca为合金组元，采用熔融浇注法制备3种Ca含量分别为1%、2%和3%的Mg-Zn-Ca三元镁合金生物可降解材料，并对3种镁合金在Hank模拟体液中的质量损失腐蚀及电化学腐蚀行为进行研究。对不同腐蚀时间的合金表面形貌以及合金组织和相成分进行分析。结果表明：镁合金的腐蚀是从镁基相的点蚀开始的，含Ca量为1%的镁合金表现出良好的抗腐蚀性能；合金中Mg2Ca相的分布显著影响合金的耐腐蚀性能，合金体中Mg2Ca相的含量随着合金中Ca含量的增加而增加，导致合金的抗腐蚀性能变差。
关键字: Mg-Zn-Ca合金；Hank溶液；电化学腐蚀；Mg2Ca相；生物降解
（1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Xiangya Hospital, Central South University, Changsha 410008, China;
3. Xiangya School of Medicine, Central South University, Changsha 410013, China）
Abstract:With elements of Zn and Ca as alloy components, three kinds of degradable ternary Mg-Zn-Ca alloys with Ca contents of 1%, 2% and 3%(mass fraction), respectively, were fabricated by melting and casting. The mass loss measurement and electrochemical corrosion technique were employed to study their corrosion behaviours in Hank’s simulated body fluid. The results based on the SEM morphology observation and analyses of structures and phases show that the corrosion of Mg alloy begins from pitting corrosion at Mg matrix. The ternary alloy with 1% Ca shows an enhanced corrosion resistance, and the existence and distribution of Mg2Ca phase in alloy significantly affect its corrosion-resisting performance. The content of Mg2Ca phase in alloy increases with the increase of Ca content, leading to a poor corrosion resistance for alloy.
Key words: Mg-Zn-Ca alloy; Hank solution; electrochemical corrosion; Mg2Ca phase; biodegradation
