医用镍钛合金表面涂覆技术研究概述

镍钛(NiTi)合金因其优异的形状记忆和超弹性性能,良好的耐腐蚀性和生物相容性,在生物医学领域得到了广泛应用。为了避免直接使用可能出现的生物不相容和细胞毒性,采用表面涂覆技术在合金表面涂覆纳米到微米量级厚度的功能薄膜,使其具有比基体更优良的生物相容性、抗腐蚀性和耐磨性等特殊功能。表面涂覆技术与其它表面改性技术相比,具有约束条件少、技术类型广、材料选择空间大等优势,目前应用最为广泛。对电化学沉积、等离子喷涂、磁控溅射、溶胶凝胶法、浸涂技术制备的涂层微观结构、力学性能和耐腐蚀等性能进行综述,并分析各技术的优缺点。随着涂覆技术的发展及制备涂层性能的进一步提高,NiTi合金在牙齿矫正丝、人工关节骨茎、血管成形环等多种医疗领域中的应用将更加广泛和深入。

Overview of the Research for Surface-Coating Technology of Biomedical NiTi Alloy

Nickel-titanium (NiTi)alloy has been widely used in biomedical field due to its excellent shape me-mory alloy,super elastic properties,good corrosion resistance and biocompatibility.To avoid the possibility of biolo-gical incompatible and cytotoxicity,surface-coating technology (SCT)has been employed to coat functional coating in the thickness from nanometer to micron dimension on the alloy surface,contributing to better biocompatibility,higher corrosion resistance and wear resistance than the matrix.Comparing with other modification methods,SCT is the most widely used currently due to the merits of low constraint condition,wide technical types and raw materials.The functional film coated by SCT is reviewed,including the electrochemical deposition,plasma spraying,magnetron sput-tering,sol-gel method and dipping technology.The microstructure,mechanical property and corrosion resistance of the alloy have been presented.Moreover,the advantages and disadvantages of these methods have been summarized. With the development of SCT and improvement of coating properties,NiTi alloy will be applied widely,such as teeth orthodontic wire,artificial joints bone and angioplasty ring.