Fast degradation rate and inhomogeneous corrosion are obstacles for magnesium alloy bio-corrosion properties. In this paper, a quaternary Mg-Zn-Ca-Mn alloy was designed by an orthogonal method and prepared by vacuum induction melting to investigate its bio-corrosion. Microstructure, corrosion morphology, and bio-corrosion properties of as-cast alloys 1 to 5 with good corrosion resistance were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction with immersion and electrochemical tests in simulated body fluid (SBF), respectively. Both the orthogonal method and in vitro degradation experiments demonstrated that alloy 3 exhibited the lowest degradation rate among the tested quaternary Mg-Zn-Ca-Mn alloys. Then, as-cast alloy 3 was treated by solid-solution and solid-solution aging. In vitro experimental results indicated that as-cast alloy 3 showed better corrosion resistance than heat-treated specimens and the average corrosion rate was approximately 0.15 mm/y. Heat-treated alloy 3 exhibited more uniform corrosion than as-cast alloy specimens. These results suggest that alloy 3 has the potential to become a biodegradable candidate material.

中文翻译：

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固溶时效处理对正交设计和真空熔炼Mg-Zn-Ca-Mn合金腐蚀行为的影响

快速降解速率和不均匀腐蚀是镁合金生物腐蚀性能的障碍。本文采用正交方法设计了一种四元Mg-Zn-Ca-Mn合金，并通过真空感应熔炼制备了其生物腐蚀。通过扫描电子显微镜、能量色散 X 射线光谱和 X 射线衍射与模拟体液中的浸泡和电化学测试，表征了具有良好耐腐蚀性的铸态合金 1 至 5 的显微组织、腐蚀形貌和生物腐蚀性能(SBF)，分别。正交方法和体外降解实验都表明，合金 3 在测试的四元 Mg-Zn-Ca-Mn 合金中表现出最低的降解率。然后，对铸态合金 3 进行固溶和固溶时效处理。体外实验结果表明，铸态合金 3 的耐腐蚀性能优于热处理试样，平均腐蚀速率约为 0.15 mm/y。热处理合金 3 表现出比铸态合金试样更均匀的腐蚀。这些结果表明合金 3 有可能成为可生物降解的候选材料。