【摘要】 采用线性极化技术测量了生物医用材料TiNi形状记忆合金 ,CoCrNiMo和CoCrNiW的腐蚀速率 ,并用动态电位扫描法考察了其阳极极化行为。结果表明 ,3种合金钝化电位区宽 ,维钝电流密度小 ,显示出优异的耐全面腐蚀性能。电位扫描曲线滞后环面积及腐蚀后扫描电镜观察显示 ,两种钴合金具有良好的耐孔蚀性能 ,而TiNi的孔蚀倾向较大 ,这是因为在TiNi合金表面夹杂的Ti2 Ni易受活性阴离子的浸蚀 ,而钴合金中的Co ,Cr,Mo和W均易在表面形成钝性氧化膜 ,抑制孔蚀的发生。接触角、动态凝血时间和溶血率的测定表明TiNi具有更优的血液相容性 ,这可能与其表面的TiO2 膜具有较小的表面张力有关。更多还原

【Abstract】 The corrosion rates and anodic polarization behavior of TiNi shape memory alloy, CoCrNiMo and CoCrNiW biomedical materials were studied respectively by linear polarization and potentiodynamic scanning techniques. The results show that three alloys have excellent corrosion resistance with the extensive passive region and low passive current density. The hysteresis loop and SEM morphology show that cobalt based alloys exhibit better resistance to pitting corrosion, while TiNi is very susceptible to it. It is due to the Ti 2Ni inclusions on the surface which is easily attacked by active anion Cl -, but in cobalt based alloys the element Co, Cr, Mo and W can form passive oxide film which inhibits pitting corrosion. The measurement of contact angle, dynamic clotting time and hemolysis rate indicate that the haemocompatibility of TiNi is the best, which is perhaps attributed to the small surface tension of TiO 2 film.[更多还原