Characteristics of a multi-component MgO-based bioceramic coating synthesized in-situ by plasma electrolytic oxidation

作     者：Nasrinsadat Azarian Seyed Mohammad Mousavi Khoei 

作者机构：Department of Mining and Metallurgical EngineeringAmirkabir University of Technology(Tehran Polytechnic)P.O.Box 15875-4413TehranIran 

出 版 物：《Journal of Magnesium and Alloys》 (镁合金学报（英文）)

年 卷 期：2021年第9卷第5期

页      面：1611-1625页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0801[工学-力学（可授工学、理学学位）] 

主　　题：Az31 magnesium alloy Plasma electrolytic oxidation Bioceramic Coating MgO-based ceramic 

摘      要：Plasma electrolytic oxidation(PEO)has held great potential for the advancement of biodegradable implants,as it helps in developing porous bioceramic coatings on the surface of magnesium alloys.In this research work,MgO-based bioceramic coatings containing the Si,P,Ca,Na,and F elements have been successfully fabricated on an AZ31 magnesium alloy plate utilizing the PEO method.The characteristic current-voltage behavior of the samples during the process was surveyed in an electrolyte containing Ca(H_(2)PO_(4))_(2),Na_(2)SiO_(3)·9H_(2)O,Na_(3)PO_(4)·12H_(2)O,NaF,and KOH with a pH of 12.5 and electrical conductivity of 20 mS/cm^(-1).The results revealed that applying a voltage of 350-400 V(that is 50-100 V higher than the breakdown limit)could greatly facilitate the synthesis of a PEO ceramic coating with fewer defects and more uniform morphology.The resulting coating was a compositionally graded bioceramic layer with a thickness in the range of 3.5±0.4 to 6.0±0.7µm,comprising the above-mentioned elements as promising bioactive agents.The synthesized ceramic features were investigated in terms of the elemental distribution of components through the thickness,which indicated a gradual rise in the Si and P contents and,conversely,a decline in the F content towards the outer surface.The growth mechanism of the PEO coating has been discussed accordingly.