机构地区: 大连理工大学材料科学与工程学院
出 处: 《功能材料》 2009年第11期1884-1887,共4页
摘 要: 研究了AZ31镁合金在Hank’s模拟体液中的腐蚀行为,包括腐蚀形貌、腐蚀速度和腐蚀电化学特征参数。通过扫描电子显微镜(SEM)比较了不同腐蚀环境中镁合金样品的腐蚀形貌特征。利用失重法测量了镁合金的腐蚀速度,并依此分析了Hank’s模拟体液中各成分对镁合金腐蚀速度的影响。测量并分析了不同pH值下的动电位动态极化曲线。结果表明,镁合金在Hank’s模拟体液中的腐蚀主要为氯离子引起的点蚀;H2PO4-和HPO42-具有缓蚀作用;pH值的升高可以提高镁合金腐蚀反应的自腐蚀电位,降低腐蚀反应的热力学倾向,稳定腐蚀过程中形成的钝化膜,从而降低了腐蚀速度。 Corrosion behavior of AZ31 magnesium alloy in Hank's simulated body fluid was investigated. It is found that the form of corrosion is dominated by pitting,which is caused by Cl^-. The individual influence of ingredients of Hank's simulated body fluid was studied by immersion test,showing that HPO4^2- and H2PO4^- can inhibit the corrosion process to a significant extent. Electrochemical test shows that elevated pH value of Hank' s simulated body fluid may increase the corrosion potential, stabilize the protective layer,and lead to lower corrosion rate.