(1. 中国科学院 金属研究所 沈阳材料科学国家(联合)实验室，沈阳 110016；
2. 伦敦大学学院 化学学院，伦敦 WC1H 0AJ)
摘 要: 采用开路电位测量、动电位极化曲线测量等方法研究医用β钛合金Ti-24Nb-4Zr-8Sn在模拟人体体液中的电化学腐蚀行为，计算该合金在模拟人体体液中的腐蚀电位(φcorr)、孔蚀电位(φpit)、腐蚀电流(Icorr)及钝化电流(Ipass)等一系列电化学参数，并与纯钛和Ti-6Al-4V合金进行比较。结果表明：与纯钛和Ti-6Al-4V合金相比，模拟人体体液中Ti-24Nb-4Zr-8Sn合金能够迅速形成保护性氧化膜，其极化曲线具有更为广阔的钝化电位区间，钝化膜状态最为稳定，腐蚀电位(φcorr)和孔蚀电位(φpit)都较大，腐蚀电流(Icorr)较小，但钝化电流(Ipass)最大，加工过程中的表面缺陷成为腐蚀的活性位置。
关键字: Ti-24Nb-4Zr-8Sn合金；磷酸盐缓冲溶液；腐蚀行为；开路电位；极化曲线
phosphate buffer saline solutions
（1. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences,
Shenyang 110016, China;
2. Department of Chemistry, University College London, London WC1H 0AJ U.K.）
Abstract:The electrochemical corrosion behavior of Ti-24Nb-4Zr-8Sn alloy in phosphate buffer saline (PBS) solutions was investigated by studying open-circuit potential and potentiodynamic polarization curve. The corrosion potential (φcorr), pitting potential (φpit), corrosion rate (Icorr) and passive current density (Ipass) were also evaluated and compared with those of purity titanium and Ti-6Al-4V alloy. The results show that the oxide film forms on Ti-24Nb-4Zr-8Sn quickly once it is put into PBS. The passivation region of this alloy in PBS is more extensive than that of pure titanium and Ti-6Al-4V alloy and its passivation-film is most stable. It shows higher φcorr and φpit and lower Icorr values compared to another two materials, but its Ipass is the highest. Pre-existed surface defects on Ti-24Nb-4Zr-8Sn might be the preferred locations for corrosion.
Key words: Ti-24Nb-4Zr-8Sn alloy; phosphate buffer saline solutions; corrosion behavior; open-circuit potential; polarization curve
