Abstract An as-cast Mg–1Zn–1Ca alloy has been soundly characterized to be used as a biodegradable material in biomedical applications. Ca and Zn additions have a great influence in the microstructure, mechanical properties and corrosion behaviour of Mg alloys. SEM examinations revealed that most of the Ca and Zn atoms form Mg2Ca and Ca2Mg6Zn3 precipitates, which distribute preferentially along the grain boundaries forming a continuous network of secondary phases. The results of nanoindentation tests show differences in hardness and elastic modulus between the α-Mg matrix and the secondary phases. The results of three-point bending tests shows that cracks propagate following the network formed by the intermetallic compounds at the grain boundaries (GBs). The evolved hydrogen after immersion in Hank’s solution of the alloy has been also estimated, showing a change in the corrosion mechanism after 160 h. The intermetallic compounds act as a barrier against corrosion, so that it progresses through the α-Mg matrix phase.

中文翻译：

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用于生物医学应用的 Mg-1Zn-1Ca 合金。第二相对机械和腐蚀行为的影响

摘要 铸态 Mg-1Zn-1Ca 合金已被充分表征为可用作生物医学应用中的生物降解材料。Ca和Zn的添加对镁合金的显微组织、力学性能和腐蚀行为有很大影响。SEM 检查表明，大多数 Ca 和 Zn 原子形成 Mg2Ca 和 Ca2Mg6Zn3 沉淀物，它们优先沿晶界分布，形成连续的第二相网络。纳米压痕测试的结果表明 α-Mg 基体和第二相之间的硬度和弹性模量存在差异。三点弯曲试验的结果表明，裂纹沿着晶界（GBs）金属间化合物形成的网络传播。还估计了浸入合金的汉克溶液后析出的氢，显示 160 小时后腐蚀机制的变化。金属间化合物作为腐蚀屏障，使其通过 α-Mg 基体相。