NiTi合金生物医用材料表面改性的研究进展

NiTi形状记忆合金作为重要的生物医用材料已经获得了广泛的应用,但Ni离子在人体环境中的释放引起了人们的忧虑.系统介绍了近年来表面改性提高NiTi合金生物相容性的主要方法、技术特点和优势.在众多的研究方法中,热氧化和自组装方法因具有工艺简单、成本低等优点而最具工业应用前景.有关NiTi合金表面涂层与细胞和血液的相互作用机理的研究亟待加强,微观方面应重视基因水平的评价,宏观方面应加强活体植入的研究.研究机构应与产业界密切配合,进一步推动相关涂层的产业化进程.     

钛合金表面涂覆羟基磷灰石的研究进展

在钛合金表面制备羟基磷灰石涂层既有良好的生物相容性又兼有良好的力学性能,作为硬组织替换材料得到了广泛的研究.总结了钛合金表面涂覆羟基磷灰石的生物相容性,详细讨论了羟基磷灰石涂层的制备方法,总结和展望了该生物涂层材料在医学中的应用所存在的问题和应用前景.     

NiTi形状记忆合金疲劳行为的研究现状

NiTi形状记忆合金具有比其它同类合金更优良的力学性能、形状记忆效应、超弹性、阻尼特性和生物相容性等特点,广泛应用于工程、民用和医学领域.综述了NiTi形状记忆合金疲劳行为的研究现状;对其疲劳行为及其机制的研究,有助于进一步提高NiTi形状记忆合金的性能并延长它的寿命.     

NiTi合金生物医用材料表面改性的研究进展

NiTi合金由于其形状记忆效应、超弹性和低模量等优良性能在生物医学领域得到广泛应用。然而,在生理环境中镍离子释放会诱发毒性和炎性反应,因此需要对其进行表面改性。从表面氧化、表面涂层和表面接枝大分子等方面综述了近年来国内外NiTi合金表面改性的研究进展,评述了各种表面改性技术的优势和缺陷,指明了NiTi合金表面改性的未来发展趋势。     

NiTi合金生物医用材料表面改性的研究进展

NiTi合金由于其形状记忆效应、超弹性和低模量等优良性能在生物医学领域得到广泛应用。然而，在生理环境中镍离子释放会诱发毒性和炎性反应，因此需要对其进行表面改性。从表面氧化、表面涂层和表面接枝大分子等方面综述了近年来国内外NiTi合金表面改性的研究进展，评述了各种表面改性技术的优势和缺陷，指明了NiTi合金表面改性的未来...     

Ti—Ni涂层的研制进展

NiTi合金具有超弹性和优良的耐磨耐蚀性能,是理想的抗空泡腐蚀材料。但NiTi合金制备成本高、加工难度大、可焊性差,这使其应用受到很大的限制。采用涂层技术沉积Ti—Ni涂层可以大大降低成本和加工难度。本文综述了国内外Ti—Ni涂层的研制现状,并重点阐述了复合涂层工艺对涂层性能的影响。     

医用NiTi合金表面改性的研究进展

近等原子比NiTi合金具有独特的力学性能,如形状记忆效应、超弹性和高阻尼效应,已成为一种新型的整形外科植入材料.但是,镍元素在生理条件下可能溶出,诱发毒性和炎性反应,限制了其在临床的广泛应用.分类介绍了几种可行的表面改性方法,均能有效地抑制镍离子的溶出,改善NiTi合金的抗腐蚀性和生物相容性,包括表面惰性涂层化、表面氧化、表面活性化和表面接枝大分子等.     

NiTi形状记忆合金在生物医用领域的研究进展

NiTi形状记忆合金由于具有良好的力学相容性、耐蚀性和生物相容性而在生物医用材料领域得到广泛应用。本文总结了医用NiTi形状记忆合金的研究现状,评述了NiTi形状记忆合金的耐蚀性和生物相容性特点,并详细讨论了NiTi形状记忆合金的表面改性问题,对NiTi形状记忆合金的医用前景进行了展望。     

表面织构与DLC涂层复合处理影响材料摩擦特性的研究进展

近些年来表面织构化与表面涂覆技术在提高摩擦学性能方面取得了良好的进展,有越来越多的研究将表面织构技术与涂覆技术进行融合,发现在适当的外界环境下合适的织构化参数与DLC涂层复合处理后显现出优异的摩擦学特性,两者间做到了1+1大于2的效果。表面织构化已经广泛的应用在改善材料摩擦性能等方面,然而其在干摩擦条件下可能并不能起到很好的润滑效果。DLC涂层被世间公认为是有效的固体润滑剂,它具有良好的减摩、抗磨性,但涂层却有着吸附力差的缺点,表面织构可以增大涂层与基材之间的有效结合强度,增加表面的腐蚀能力,进而可以提高涂层的摩擦学性能、腐蚀性能、生物相容性。织构化与DLC涂层的结合可以在航空、汽车、机械等领域得到广泛应用,进而提高产品的性能和可靠性。主要介绍表面织构化与DLC涂层复合改性处理后材料的摩擦磨损特性。并从织构的几何参数、实验条件、接触方式、摄入元素、涂层厚度以及仿真分析等几方面进行阐述。为帮助后续的研究方向提供参考。最后对织构与涂层复合改性方面的发展趋势进行展望。     

NiTi合金表面液相阴极等离子体沉积氧化铝陶瓷涂层的研究

在NiTi合金表面通过液相阴极等离子体技术制备了氧化铝(Al2O3)陶瓷涂层。采用X射线衍射和扫描电镜对涂层的相组成以及表面形貌进行了表征和分析,证实在材料表面形成了由α-Al2O3和γ-Al2O3组成的涂层,发现涂层具有粗糙多孔结构。在模拟体液中对NiTi合金的Ni离子释放情况进行了检测,发现液相阴极等离子体改性后显著降低了Ni离子的释放。为NiTi合金植入体的表面改性提供了一条新途径。     

Fabrication and biocompatibility of polyethyleneimine/heparin self-assembly coating on NiTi alloy

NiTi alloy has been used widely as biomaterials. But because of toxic effects possibly caused by excess Ni ions released during the corrosion process in the physiological environment, it is still a controversial material. Fabricating medicine-loaded coating, which is expected to decrease the release of Ni ions and improve the biocompatibility of the materials, is a potential way to solve the problem. In this paper, NiTi alloy is coated by polyethyleneimine/heparin films via layer-by-layer (LBL) self-assembly method. UV-Vis, FT-IR, atomic force microscopy (AFM) and contact angle measurements are used to characterize the microstructure of coatings and select the best fabrication conditions. Potentiodynamic polarization researches in sodium chloride and dynamic clotting time experiment are utilized to study its corrosion resistance capability and biocompatibility of coatings, respectively. The results indicate that PEI/heparin multilayer coating can improve the biocompatibility of NiTi alloy surface.     

镍钛合金在医疗器械领域应用和表面改性研究进展

镍钛合金基于特有的超弹性、形状记忆效应,广泛应用于医疗器械领域。其中超弹性表现为大变形下的弹性应变,应用于血管和腔道介入器械、口腔正畸丝、根管器械等;形状记忆效应可实现低温下易变形、体温下自回复,应用于热激活正畸丝、骨科、矫形外科、缝线等。此外,可通过多样化的表面改性技术,提升镍钛合金的生物相容性、腐蚀抗性、摩擦磨损性能,优化产品性能,拓展其在医疗器械制品中的应用范围。     

Ti-Ni基记忆合金复合材料的研究进展

Ti-Ni形状记忆合金因具有优异的形状记忆效应和超弹性及良好的耐腐蚀性、生物兼容性等诸多优点,被广泛应用于航空航天、机械、电子、生物医用等领域。Ti-Ni基复合材料中Ti-Ni基体和增强相之间的交互作用可使其集优异力学性能、功能特性于一体。本文主要阐述了近几年采用不同方法制备的Ti-Ni形状记忆合金复合材料的最新研究进展,包括微观组织结构的演化规律、马氏体相变行为及力学性能和应变恢复特性。另外,对当前Ti-Ni形状记忆合金复合材料的制备技术存在的问题及未来的发展方向进行了分析和展望。      

NiTi superelastic orthodontic archwires with polyamide coating

Twenty orthodontic archwires with 55.2 % Ni and 44.8 % Ti (% weight) were subjected to a dipping treatment to coat the NiTi surface by a polyamide polymer. It has been selected a Polyamide 11 due to its remarkable long lasting performance. The transformation temperatures as well as the transformation stresses of the NiTi alloy were determined in order to know whether the coating process can alter its properties. The adhesive wear tests have been demonstrated that the wear rates as well as the dynamic friction coefficients μ of polymer coated wires are much lower than metallic wires. The corrosion studies have shown that the use of this polymer, as coating, seals the NiTi surface to prevent corrosion and the release of nickel ions. The average decrease of Ni ions release due to this coating is around 85 %.     

溶胶-凝胶法制备TiO2与SiO2-TiO2薄膜对医用NiTi合金的表面改性

采用溶胶－凝胶法制备TiO2与SiO2-TiO2薄膜，对医用NiTi合金进行表面改性处理，利用X射线衍射（XRD）、原子力显微镜（AFM）、划痕试验和电化学腐蚀试验等手段系统研究了薄膜结构、形态及性能。通过动态凝血时间和血小板粘附的测量研究和评价了薄膜的体外血液相容性。结果表明，在一定范围内，较高热处理温度有利于薄膜与基体间的结合强度和耐腐蚀性的提高；NiTi合金表面镀TiO2与SiO2-TiO2薄膜后，其血液相容性明显提高。     

Characterization of Sol-gel-derived TiO2 and TiO2-SiO2 Films for Biomedical Applications

In order to improve the corrosion resistance and biocompatibility of NiTi surgical alloy, TiO2 and TiO2-SiO2 thin films were prepared by sol-gel method. The surface characteristics of the film, which include surface composition, microstructure and surface morphology, were studied by X-ray diffraction (XRD), atomic force microscopy (AFM) and X-ray photoelectron spectra (XPS), respectively. A scratching test was used to assess the interface adhesive strength between the film and substrate. The corrosion resistance of NiTi alloy coated with oxide films were studied by anodic polarization curves measurement in biological solution. Additionally, a preliminary study of the in vitro bioactivity of the films was conducted. The results indicated that TiO2 and TiO2-SiO2 (Ti/Si=4:1) films have higher electrochemical corrosion resistance and can be used as protective layers on NiTi alloy. In addition, TiO2-SiO2 composite films have better bioactivity than TiO2 film.     

物理气相沉积在耐腐蚀涂层中的应用

PVD(物理气相沉积)作为一种新型绿色的镀膜技术,由于涂层具备硬度高、耐磨性好、摩擦系数低、化学性能稳定、耐热耐氧化的特点,使其在机械、电子和光学行业得到广泛应用。近些年来随着PVD技术应用领域的不断扩展,对涂层的性能提出了更高要求,在保障力学性能的同时,如何提高涂层耐蚀性成为研究热点。概述了PVD技术应用于材料防腐的相关研究,综述了PVD涂层的成分、结构与耐蚀行为的关系,同时分别阐述了在PVD技术中提高涂层耐蚀性能的方法与机理。     

Structure and properties of TiC/Ti coatings fabricated on NiTi by plasma immersion ion implantation and deposition

A titanium carbide (TiC) nanostructured coating and Ti intermediate layer are fabricated on NiTi by plasma immersion ion implantation and deposition (PIII&D) to improve the surface properties. The chemical composition and structure are determined by X-ray diffraction, Auger electron spectroscopy, scanning electron microscopy, and atomic force microscopy. Nano-indentation is used to evaluate the mechanical properties of the thin film and the biological characteristics are assessed by electrochemical measurement and soaking tests in simulated body fluids. Based on the potentiodynamic polarization and Ni release data after the polarization test, the Ti/TiC nanostructure coating has better corrosion resistance compared to the NiTi substrate and there is significantly less Ni ion release from the NiTi substrate into the simulated body fluids than the uncoated NiTi alloy.