生物医用镍钛合金表面钽涂层腐蚀行为研究

目的 在模拟体液环境中,研究钽(tantalum, Ta)涂层对生物医用镍钛形状记忆合金(NiTi shape memory alloy, NiTi SMA)抗腐蚀性能的影响.方法 对镍钛形状记忆合金试样,运用等离子喷涂技术在其表面形成一层400μm厚的钽涂层.通过模拟体液环境下电化学测量法对比涂层前后的试样抗腐蚀性能...

Corrosion Behavior of Tantalum Coating on Biomedical NiTi Alloy

Objective To investigate the corrosion resistance effects of tantalum （Ta） coating on biomedical NiTi shape memory alloy （NiTi SMA） in the simulated body fluid （SBF）. Methods The NiTi SMA specimen was coated with a thickness of 400μm Ta coating by plasma spraying. The corrosion resistance strength of the specimen before and after coating Ta was compared. The existence of galvanic corrosion between Ta and NiTi SMA was measured by electrochemical method. Results The anodic polarization curves indicated that, after coating Ta the NiTi SMA specimen showed reduced passive current intensity, increased polarization resistance, and increased natural corrosion potential and breakdown potential. The galvanic current-time curve indicated that, the galvanic current density of Ta-NiTi SMA was minimal. Conclusion The surface modification of coating Ta on NiTi SMA can improve corrosion resistance of the base metal. There is no galvanic corrosion between Ta coating and NiTi SMA substrate.