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采用气氛保护加机械搅拌方法熔炼Mg-xZn-Ca-yHA(x=1,3,5;y=0,1,3,5)系列合金及其复合材料。通过金相显微镜(OM)和场发射扫描电子显微镜(FESEM)观察其铸态微观组织;X-射线衍射仪(XRD)分析物相组成;电化学和体外浸泡实验测试挤压态复合材料的耐腐蚀性能。结果表明,纳米羟基磷灰石(HA)颗粒可添加至Mg-Zn-Ca合金中,并在冶炼温度下脱水,转变成为了β-Ca3(PO4)2,同时显著细化基体合金的晶粒。其中,添加质量分数1%HA的复合材料具有最好的耐腐蚀性能。Mg-3Zn-Ca/1HA复合材料的腐蚀电位、腐蚀电流密度和腐蚀速率分别为–1.582 V,1.47μA/cm和14.19 mm/a,明显优于Mg-3Zn-Ca合金的–1.662 V,2.22μA/cm和21.28 mm/a。而添加3%HA的Mg-3Zn-Ca-3HA复合材料由于HA在基体中的部分团聚导致其耐腐蚀性能较Mg-3Zn-Ca合金有所下降。
Mg-xZn-Ca-yHA (x = 1,3,5; y = 0,1,3,5) series alloys and their composites were melted by atmosphere protection and mechanical stirring. The as-cast microstructure was observed by optical microscope (OM) and field emission scanning electron microscopy (FESEM). The phase composition was analyzed by X-ray diffraction (XRD). The electrochemical and in vitro soak test Corrosion performance. The results show that the nano-hydroxyapatite (HA) particles can be added to the Mg-Zn-Ca alloy and dehydrated at the smelting temperature to transform into β-Ca3 (PO4) 2 while significantly refining the grain size of the matrix alloy . Among them, the composite material with the mass fraction of 1% HA has the best corrosion resistance. The corrosion potential, corrosion current density and corrosion rate of Mg-3Zn-Ca / 1HA composites were -1.582 V, 1.47 μA / cm and 14.19 mm / a, respectively, which were significantly better than those of Mg-3Zn-Ca alloy μA / cm and 21.28 mm / a. Compared with Mg-3Zn-Ca alloy, the corrosion resistance of Mg-3Zn-Ca-3HA composites with 3% HA addition decreased due to the partial agglomeration of HA in the matrix.