A magnesium phytic acid/hydroxyapatite composite coating was rapidly prepared on AZ31 Mg alloy sub-strate by microwave assisted method.The surface morphology and composition,as well as the corrosion resistance, were characterized by FESEM,EDS,XRD and electrochemical tests.The influence of pH value of phytic acid solu-tion on the microstructure and corrosion resistance of the magnesium phytic acid/hydroxyapatite coatings was inves-tigated.The biodegradation and biomineralization behavior of Mg alloy and its coatings in simulated body fluid (SBF)were evaluated via immersion tests.The results show that when the pH value of phytic acid solution is 5.0, the magnesium phytic acid/hydroxyapatite composite coating is uniform and crack-free,with a good interface bond-ing to the substrate.The electrochemical measurements in SBF reveal that magnesium phytic acid/hydroxyapatite coating with pH=5.0 exhibits the best corrosion resistance compared with those with other pH values.The magne-sium phytic acid/hydroxyapatite composite coating can induce apatite deposition and effectively improve the corrosion resistance of Mg alloy in SBF.%采用微波辅助法在AZ31镁合金表面制备了植酸镁/羟基磷灰石(PA/HA)复合涂层.利用FESEM、EDS、XRD和电化学性能测试等方法表征涂层的表面形貌、物相组成以及耐蚀性能,探究了植酸溶液的pH值对PA/HA复合涂层形貌及耐蚀性能的影响,并通过浸泡实验研究了镁合金及PA/HA复合涂层在模拟体液(SBF)中的降解矿化行为.结果表明:在植酸预处理中,植酸溶液的pH=5.0时制备得到的PA/HA复合涂层表面均匀、无裂纹,与镁合金基底的界面结合良好;并且在此pH值下PA/HA复合涂层包覆镁合金样品的交流阻抗最大,自腐蚀电流密度最小,说明其耐蚀性最好.在SBF中,PA/HA复合涂层能够快速诱导磷灰石的生成,并显著提高镁合金基底的耐蚀性能.
展开▼
