Mg_(67)Zn_(28)Ca_(5)合金激光表面非晶化处理及其生物腐蚀性能研究  

Investigation on the Laser Amorphization of Mg_(67)Zn_(28)Ca_(5) Alloy and Its Bio-corrosion Resistance

作　　者：宋婕 丁浩 丁红燕 周广宏 Song Jie;Ding Hao;Ding Hongyan;Zhou Guanghong(Faculty of Mechanical&Material Engineering,Huaiyin Institute of Technology,Huaian 223003,China;School of Mechano-Electronic Engineering,Suqian University,Suqian 223800,China)

机构地区：[1]淮阴工学院机械与材料工程学院,江苏淮安223003 [2]宿迁学院机电工程学院,江苏宿迁223800

出　　处：《稀有金属材料与工程》2023年第10期3539-3546,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51875231,51775221)。

摘　　要：Mg-Zn-Ca合金因其较好的力学性能、良好的生物相容性和优异的可降解性,有望在人体骨组织植入材料得到推广应用,但由于耐生物腐蚀性能较差,限制了其临床的进一步应用。通过激光表面非晶化处理对共晶成分的Mg_(67)Zn_(28)Ca_(5)合金进行了表面改性,研究了激光扫描速度对Mg_(67)Zn_(28)Ca_(5)合金表面非晶复合涂层的显微组织和相组成的影响;测试了合金表面改性前后在人工模拟体液(SBF)中的生物腐蚀行为。研究结果表明,经激光表面非晶化处理后样品表面主要由大量的非晶和极少量的晶态物质组成。随着激光扫描速度的增大,合金表面形成的非晶相越多。晶相的形成主要是受到后续激光加工的热影响而产生热激活,部分非晶相发生了形核长大。与铸态镁合金相比,更大激光扫描速度下制备的非晶复合涂层在SBF中的腐蚀电位正向偏移了0.16 V,腐蚀电流密度是铸态镁合金的7.6%。合金表面少量晶相的存在,使之成为表面腐蚀的活性通道,对合金表面的腐蚀性能产生轻微的影响。通过激光表面非晶化处理,可有效改善Mg_(67)Zn_(28)Ca_(5)合金的耐生物腐蚀性能,在生物医用植入物方面展现出良好的应用前景。Mg-Zn-Ca alloys are expected to be widely used in human bone tissue implant materials due to their excellent mechanical properties,good biocompatibility and excellent degradability.However,the poor bio-corrosion resistance of magnesium alloys limits their further clinical application.The surface of Mg_(67)Zn_(28)Ca_(5) alloy with eutectic composition was modified by laser amorphization.The effect of laser scanning speed on the microstructure and phase composition of Mg_(67)Zn_(28)Ca_(5) alloys amorphous coating were studied.The bio-corrosion behavior of the alloy surface before and after laser amorphization in artificial body fluid(SBF)was tested.The results show that a large amount of amorphous materials and a small amount of crystal materials were formed on the surface of the specimens after laser amorphization.With the increase in laser scanning speed,more amorphous phase were formed on the alloy surface.The formation of crystal phases was mainly caused by thermal activation due to the thermal influence of subsequent laser processing,and some crystal phase nucleated and grew up.Compared with the as-cast magnesium alloy,the corrosion potential of the amorphous layer prepared under the higher laser scanning speed in SBF solution was positively shifted by 0.16 V,and the corrosion current density is 7.6% of the value of as-cast samples.The existence of a small amount of crystal phase on the alloy surface became an active channel to form surface corrosion,which had a slightly negative impact on the corrosion performance of the alloy surface.The biological corrosion resistance of Mg_(67)Zn_(28)Ca_(5) alloy can be effectively improved by laser amorphization treatment,which shows a good application prospect in biomedical implants.

关 键 词：Mg_(67)Zn_(28)Ca_(5)合金 激光非晶化 表面改性 生物腐蚀 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TG174.4[金属学及工艺—金属材料]