【摘 要】
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The early corrosion control of biomedical magnesium alloy is an important measure to determine its good per-formance during implantation into human body.The dep
【机 构】
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School of Mechanics and Civil & Architecture Northwestern Polytechnical University,Xi’an,710129,Chin
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The early corrosion control of biomedical magnesium alloy is an important measure to determine its good per-formance during implantation into human body.The deposition of calcium phosphate biological coating is the most effective solution at present.In this paper,hydroxyapatite (HAP) coating was hydrothermal synthesized on the surface of AZ31B magnesium alloy,and the influence mechanism of hydrothermal synthesis temperature,time and solution concentration was investigated.The synthesis conditions and deposition mechanism of hydroxy-apatite coating without DCPA (CaHPO4) were proposed.The surface morphology of the coating was observed by field emission electron scanning microscope (FESEM).The types and contents of microelements in the material were analyzed by energy disperse spectroscopy (EDS).Fourier transform infrared spectroscopy (FTIR) was used to analyze the functional group information of the coating surface.The corrosion resistance of different experimental groups was studied by electrochemical test.The results showed that when the calcium phosphate solution con-centration was 0.1 mol/L and the calcium/phosphorus ratio was 1.67,the coating had better morphology structure and corrosion resistance,and the calcium/phosphorus ratio of HAP crystals reached 1.58,the epit of the prepared AZ31B-HAP coating by bare metal increased from-1.51 V to-1.18 V,the impedance value reached 1.0 × 105 Ωcm2,and the early corrosion of magnesium alloy substrate was effectively delayed.
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