骨折内固定用新型Mg-Zn-Ca/HA复合材料的成分、组织结构与性能  

Composition, Microstructure and Properties of the Fracture Fixation with New Mg-Zn-Ca/HA Composites

作　　者：曹耿华[1] 毕衍泽[1] 陈民芳[1,2] 刘德宝[1,3] 由臣[1,2] 

机构地区：[1]天津理工大学,天津300384 [2]天津市光电显示材料与器件重点实验室,天津300384 [3]显示材料与光电器件省部共建教育部重点实验室,天津300384

出　　处：《稀有金属材料与工程》2013年第8期1632-1637,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51071108);天津市自然科学基金(09JCZDC18500)

摘　　要：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。A series of Mg-xZn-Ca-yHA （x=1, 3, 5; y=0, 1, 3, 5） composites were smelted in steel crucibles under protective gas （99.6%NE＋0.4%SF6） with mechanical mixing. The microstructure of the as-cast composites was investigated by optical microscopy （OM） and scanning electron microscopy （SEM）, phase analyses were carried out with X-ray diffractometer （XRD） and corrosion properties were studied by means of electrochemical measurements and in vitro immersion test. The result demonstrate that the nano-HA particles can be added into Mg-Zn-Ca alloys and translated into fl-Ca3（PO4）2 at the smelting temperature, meanwhile the grain size of the as-cast composites significantly decreases with the increasing of HA content. The composites with 1 wt% HA addition show the best corrosion resistance. The corrosion potential, corrosion current density and average corrosion rate of Mg-3Zn-Ca-lHA are -1.582 V, 1.47 ktA/cm2 and 14.19 mm/a, respectively. They are superior to that of the Mg-3Zn-Ca alloy, whose corrosion potential, corrosion current density and average corrosion rate are -1.662 V, 2.22 μA/cm2 and 21.28 mm/a, respectively. When HA content is up to 3 wt%, the corrosion resistance of Mg-3Zn-Ca-3HA composites is decreased, due to the conglomeration of HA in the matrix but even better than that of pure alloy.

关 键 词：纳米HA颗粒 Mg—Zn—Ca HA复合材料 微观组织 体外降解 腐蚀性能 

分 类 号：TB33[一般工业技术—材料科学与工程]