Structure and in vitro bioactivity of ceramic coatings on magnesium alloys by microarc oxidation
Structure and in vitro bioactivity of ceramic coatings on magnesium alloys by microarc oxidation
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DOI：
10.1016/j.apsusc.2016.03.028
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发表时间：
2016-12
影响因子：
6.7
通讯作者：
Huijun Yu;Q. Dong;J. Dou;Yaokun Pan;Chuanzhong Chen
中科院分区：
文献类型：
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作者：
Huijun Yu;Q. Dong;J. Dou;Yaokun Pan;Chuanzhong Chen
镁及其合金有可能作为轻质、可降解、生物兼容和生物活性的骨科植入物用于承重应用。然而，严重的局部腐蚀和较高的腐蚀率阻碍了它们的进一步临床应用。微弧氧化是一种在镁合金表面制备保护性陶瓷涂层的简单、可控、高效的电化学技术。采用含硅酸盐的电解液进行微弧氧化，在ZK61合金表面形成陶瓷生物活性涂层。用X射线衍射仪、透射电子显微镜、扫描电子显微镜和电子探针对涂层的结构特征和元素分布进行了研究。MAO样品分别在模拟体液(SBF)中浸泡7天和14天。用傅里叶变换红外光谱(FTIR)研究了浸渍涂层的表面特征。结果表明，这些微弧氧化涂层结晶度较低，主要由氧化镁、硅酸镁和硅酸镁组成。涂层表面是疏松的。在SBF浸泡过程中，MAO涂层表面发生了骨状磷灰石的形核和析出。微弧氧化涂层提高了基材的耐腐蚀性。
Magnesium and its alloys have the potential to serve as lightweight, degradable, biocompatible and bioactive orthopedic implants for load-bearing applications. However, severe local corrosion attack and high corrosion rate have prevented their further clinical use. Micro-arc oxidation (MAO) is proved to be a simple, controllable and efficient electrochemistry technique that can prepare protective ceramic coatings on magnesium alloys. In this paper, electrolyte containing silicate salts was used for microarc oxidation to form ceramic bioactive coatings on the ZK61 alloy substrate. The structure characteristics and element distributions of the coating were investigated by XRD, TEM, SEM and EPMA. The MAO samples were immersed in simulated body fluid (SBF) for 7 and 14 days, respectively. The surface characteristic of the immersed coatings was investigated by Fourier-transform infrared (FTIR) spectroscopy. The results show that these MAO coatings have low crystallinity and are mainly composed of MgO, Mg2SiO4and Mg2Si2O6. The coating surface is porous. During the SBF immersion period, the nucleation and precipitation of bone-like apatites occur on the MAO coating surface. The corrosion resistance of the substrate is improved by the MAO coatings.