新型医用Ti75,TiZr合金的生物腐蚀行为研究

Electrochemical Behavior of Titanium Alloys under Biological Conditions

对两种不含钒元素的新型钛合金(Ti75合金, TiZr合金)及Ti6Al4V合金的腐蚀行为进行了研究,尤其是在体外将0.9% NaCl溶液、细胞培养液及活性细胞等作为腐蚀液,比较了几种钛合金的腐蚀行为。结果表明几种钛合金在自腐蚀电位(Er)、腐蚀电位(Ec)和维钝电流密度 (Ip)等方面均表现出良好的电化学行为。其生物腐蚀行为在接近人体生理环境的细胞培养液及活性细胞环境中,与在0.9% NaCl溶液中有很大差异。Ti75合金与TiZr合金在生物环境中比Ti6Al4V合金具有更高的稳定性。

Titanium and its alloys are recognized as biocompatible materials for use in medical devices. During the last few years a new generation of Ti alloys has been created with the aim of removing vanadium as an alloying element (e.g. in Ti-6Al-4V), the potential cytotoxic effect of which has been demonstrated in several investigations. The scope of the present work is to establish the corrosion behaviors of some new titanium alloys (Ti75 alloy, TiZr alloy) in 0.9% NaCl electrolyte and in particular under biological conditions. The results showed that the new alloys generally exhibit good electrochemical behaviors in rest potential (E-r), corrosion potential (E-c) and passive current density (I-p). A remarkable difference is encountered with respect to the electrolyte RPMI alone induces a favorable E-c and an increased I-p whereas the presence of cells decreases the I-p and the E-c with respect to 0.9% NaCl and RPMI. So RPMI with or without cells is a more relevant physical electrolyte than 0.9% NaCl. The new titanium alloys show by their electrochemical behavior some advantages as compared to Ti6Al4V.