仿生涂层控制MgZnSrLa合金降解速率的研究∗

摘要

镁及其合金具有优良的生物相容性能、可降解性，避免二次手术，可以代替不锈钢、钛合金等传统的医用金属材料，具有广阔的发展前景。然而，目前镁合金作为生物材料面临最大的问题就是降解速率过快、力学性能低，这严重限制其在临床中的应用。利用仿生法在 MgZnSrLa 合金上制备羟基磷灰石(HA)涂层，利用 X 射线、扫描电子显微镜以及能谱分析仪对涂层进行表征。通过在人体模拟液中的电化学腐蚀、浸泡腐蚀实验，对比有无涂层合金试样的耐蚀性，结果表明有涂层的MgZnSrLa合金在人体模拟液(SBF)中有较好的耐腐蚀性能。%Magnesium and Magnesium alloys are considered to have wide developmental foreground due to their good biocompatibility and degradability,they would partially replace stainless steel,titanium alloys and other traditional medical metal materials,and the secondary surgery can be effectively avoided.However,the biggest problem of magnesium alloys as biomaterial is high corrosion rate and low mechanical properties,which badly confines their application in clinic.Hydroxyapatite (HA)was coated on surfaces of MgZnSrLa alloys by biomi-metic technique,and the coatings were studied by X-ray diffraction,scanning electron microscopy and energy dispersive spectroscopy.The corrosion properties of MgZnSrLa alloys with and without coating were researched by immersion corrosion and electrochemical corrosion tests in simulated body fluid (SBF).The results show that the MgZnSrLa alloy with coating exhibits better corrosion properties than without coating in SBF.