国外生物医用钛合金的发展现状

Development and Application of Biomedical Ti Alloys Abroad

摘要:

综述了近年来国外在生物医用钛及钛合金方面的研究与开发现状。为了取代普遍使用的Ti-6Al-4V合金，研发了多种无毒无敏感性元素、低弹性模量、高力学性能的新型β型钛合金；采用多孔技术并调节孔隙率，使材料的弹性模量与人体骨骼基本相当，通过将聚合物渗入到多孔钛的方法弥补多孔钛强度的降低，并使材料具有更好的生物相容性；为适应矫形外科领域的需求，开发了多孔TiNi超弹性形状记忆合金，从而克服了骨与植入体之间结合力弱以及弹性模量不匹配的弊端。此外，研发了多种不含毒性和过敏性元素的β型超弹性形状记忆钛合金，可以替代TiNi合金而更安全地应用于医学领域；开发了多种钛的表面改性技术，通过改性层的沉积及表面硬化使植入体的生物相容性和抗磨损性得到提高。

Abstract:

Research and development of titanium and titanium alloys for biomedical applications abroad during last years were reviewed. Several kinds of low Young’s modulus, high mechanical properties, nontoxic and allergy-free b-type titanium alloys were developed to replace the widely used Ti-6Al-4V alloy. In order to reduce the Young’s modulus of the metals to a level similar to that of cortical bone, it is very effective to make titanium and its alloys porous and to adjust their porosity. The decrease in the strength of porous titanium can be significantly inhibited by penetrating polymer into the porous titanium through pressing, by which the biocompatibility can also be further improved. In order to meet the requirements in orthopaedic surgery field, porous TiNi superelastic shape memory alloy has been developed to overcome the drawbacks like weak interfacial bonds and mismatch of Young’s modulus between bone and implants. In addition, several kinds of nontoxic and allergy-free b-type superelastic shape memory titanium alloys were developed to substitute TiNi alloy with the aim to assure a more safety use in medical field. A tremendous number of surface modification techniques related to the deposition of modified surface layer and surface hardening were developed to improve the biocompatibility and wear resistance of titanium implants.