表面技术2023，Vol.52Issue(12)：315-334,20.DOI:10.16490/j.cnki.issn.1001-3660.2023.12.026
医用镁合金微弧氧化/有机复合涂层的研究现状及演进方向
Research Status and Evolution Direction of Micro-arc Oxidation/Organic Composite Coating on Medical Magnesium Alloy Surface
摘要
Abstract
Good biosafety,biocompatibility and valuable self-degradation properties endow medical magnesium and magnesium alloys with great potential to replace inert implant materials in the field of traditional clinical applications.The excessive degradation rate of magnesium alloy,however,leads to its premature loss of structural integrity and mechanical support,being unable to complete the effective service time necessary for tissue healing of the implant site.At the same time,it is also its excessive degradation rate that leads to the intensification of hydrogen evolution reaction of magnesium alloy.Because it cannot be absorbed by the human body in a short time,the excessive H2 will easily gather around the implant or form a subcutaneous airbag,which will not only cause the inflammation of the implant site,but also hinder the adhesion and growth of cells in the implant,limiting its clinical application prospects.Surface modification technology can effectively delay the degradation rate of medical magnesium and magnesium alloys,and reduce the rate of hydrogen evolution. Firstly,starting from the structure and performance characteristics of organic materials(phytic acid(PA),chitosan(CS),stearic acid(SA),dopamine(DA),polylactic acid glycolic acid copolymer(PLGA),polylactic acid(PLA),and polycaprolactone(PCL)),the mechanism of improving the corrosion resistance of magnesium and magnesium alloys by a single organic coating was analyzed,and the performance weaknesses of a single coating were also pointed out:①Micro arc oxidation(MAO)is an anodic oxidation process that generates a highly adhesive ceramic oxide coating on the surface of an alloy immersed in an electrolyte through high voltage(up to 300 V)spark discharge.The continuous high voltage discharge and the bubbles generated by the reaction bring about the inevitable occurrence of a large number of volcanic micropores and cracks in the coating.The diversity of discharge modes also gives rise to the unpredictable morphology of micropores and cracks.Therefore,the preparation of a single MAO coating on different alloy surfaces does not only require proper adjustment of MAO electrical parameters(current density,voltage,duty cycle,frequency,oxidation time)and the coupling effect of its electrolyte system to decrease(small)the pores and cracks on the MAO coating surface,but also increases the sealing process at the later stage.② A single organic coating has a low bonding strength with magnesium alloy,being easy to flake off.These performance weaknesses limit the protection effect of a single coating on magnesium alloy degradation. Secondly,from the perspectives of bonding strength,corrosion resistance,and versatility(biosafety,biocompatibility,induced regeneration,antibacterial and antibacterial properties,drug loading and sustained-release properties,and so on),the structural characteristics and advantages of each MAO/organic composite coating were elaborated in detail.It has revealed that MAO/organic composite coating has an enormous application potentiality in the field of surface modification of medical magnesium and magnesium alloys,thanks to its good corrosion inhibition and degradation performance.On this basis,it is clearly pointed out that,in order to achieve the biological activity and versatility of medical magnesium alloy implant materials,the best way is to adopt the MAO/PCL(MAO/CS)composite coating as the base coating and make the cross combination of PCL(CS)coating and other coatings.Finally,the evolution direction of magnesium alloy MAO/organic composite coating is scientifically predicted.关键词
镁合金/微弧氧化/有机材料/复合涂层/演进方向Key words
magnesium alloy/micro-arc oxidation/organic materials/composite coating/evolution direction分类
矿业与冶金引用本文复制引用
冀盛亚,常成,常帅兵,倪艳荣,李承斌..医用镁合金微弧氧化/有机复合涂层的研究现状及演进方向[J].表面技术,2023,52(12):315-334,20.基金项目
河南省科技攻关项目(222102310337,222102240104,232102241029) （222102310337,222102240104,232102241029）
博士科研资金(9001/KQ1846)Henan Province Science and Technology Research Project(222102310337,222102240104,232102241029) （9001/KQ1846）
Doctoral Research Funding(9001/KQ1846) （9001/KQ1846）
