AZ91镁合金表面电化学沉积羟基磷灰石涂层的制备及其耐蚀性

摘要

采用电化学沉积方法在AZ91镁合金表面制备了羟基磷灰石(HA)涂层,研究了电沉积工艺参数对羟基磷灰石涂层形貌和相组成的影响,并通过腐蚀浸泡试验、极化曲线测试等方法对该涂层的耐蚀性进行了研究.结果表明:当溶液pH为4.5,温度为60℃时,涂层的致密性最好,呈放射状的结构,主要成分为HA相,涂层的厚度约为60～70μn,与基体结合较好;HA涂层对镁合金基体具有较好的保护作用,显著提高了基体合金在生理溶液中的耐蚀性.%Hydroxyapatite (HA) coatings were prepared on the sudace of AZ91 magnesium alloy by electrochemical deposition method.The effects of electrodeposition parameters on phase composition and morphology of the HA coatings were studied.And the corrosion resistance of the HA coatings was investigated by corrosion immersion testing and polarization curve testing.The results show that the HA coating prepared at pH value of 4.5 and temperature of 60 ℃ was the most compact,was composed of HA and presented radical structure with a thickness of about 60-70 pm.The HA coating had good protection for AZ91 magnesium alloy and significantly improved the alloy corrosion resistance of AZ91 magnesium alloy in physiological solution.