钽注入医用316L不锈钢的表面结构与性能

Surface Structure and Properties of Ta--implanted Biomedical 316L Stainless Steel

采用钽离子注入对医用316L不锈铜进行表面改性，并以镍钛合金作为对照。钽注入后316L试样的表面形貌没有发生明显变化．而镍钛合金表面形成了纳米结构。X射线光电子能谱分析在注入试样的外表面层和基体较大的深度内检测到Ta2O5、TaC和金属Ta。水接触角测量表明钽注入后两种材料变得更为疏水（接触角大于95°）。在0．9％NaCI溶液中的动电位极化测试表明，注入后两种材料的耐蚀性均提高．但由于改性层厚度有限．316L试样的耐蚀性仍然较弱。

Surface modification of biomedical 316I. stainless steel by Ta implantation is studied in comparison with NiTi alloy. The 316L sample has no obvious variation of surface morphology, different from NiTi alloy on which nanostructures are formed after Ta implantation. X--ray photoelectron spectroscopy reveals that Ta2O5, TaC and metallic Ta are detected at the outer surface layer and within relatively large depths of the substrates. Water contact angle measurement shows that the two materials become more hydrophobic （contact angle 〉 95°） after Ta implantation. The potentiodynamic polarization test in 0.9% NaCl solution shows that corrosion resistance of the two materials is improved after implantation, but it is still weak for 316L sample due to the limited thickness of the modification layer.