共查询到18条相似文献,搜索用时 203 毫秒
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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。 相似文献
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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... 相似文献
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医用多孔NiTi合金表面微弧氧化改性研究 总被引:2,自引:0,他引:2
为解决多孔Ni Ti合金耐蚀性降低和Ni离子释放量增大而引起的使用安全性问题.本文采用微弧氧化技术对医用多孔Ni Ti合金进行表面改性处理,研究结果表明,微弧氧化处理并未改变多孔Ni Ti合金原有的孔隙结构和孔隙率,只在其外表面和孔隙内表面均形成了典型的微弧氧化多孔涂层.该涂层主要由氧化铝相组成,并含有少量的Ti和Ni元素,且外表面涂层的Ti和Ni含量要略低于孔隙内表面涂层.微弧氧化涂层提高了多孔Ni Ti合金的表面接触角,将原有的亲水表面转变成了疏水表面.经微弧处理后,多孔Ni Ti合金的耐蚀性较基体提高了1个数量级以上,Ni离子释放量也较基体降低了1个数量级以上. 相似文献
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NiTi合金生物医用材料表面改性的研究进展 总被引:2,自引:0,他引:2
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. 相似文献
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近等原子比的NiTi合金以其优异的特性在临床医学得到广泛应用,但是由于Ni离子溶出引致的潜在生物毒性以及无生物活性,抑制了NiTi合金在生物医用领域的进一步发展。为了改善上述缺陷,对NiTi合金进行表面处理成为当前国内外NiTi合金研究的热点。从不同的改性工艺出发,全面阐述了近年来国内外对致密态和多孔态NiTi合金进行表面改性的研究进展,对各种方法可能出现的问题进行了分析,指出现有的各种表面改性方法不能有效实现对多孔NiTi合金内部孔隙进行改性,并针对这一症结提出了采用原位氮化法对多孔NiTi合金进行改性的可行性。 相似文献
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采用低压等离子渗氮工艺对NiTi合金进行了渗氮处理.氮化处理后NiTi合金表面硬度升高.XRD测试结果表明在合金表面形成了一层TiN涂层,在TiN涂层下为Ni3Ti相.电化学腐蚀测试表明经氮化处理后合金的耐腐蚀能力大为提高. 相似文献
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In this investigation, plasma immersion ion implantation and deposition (PIIID) was used to fabricate a (Ti, O, N)/Ti coating on NiTi shape memory alloy (SMA) to improve its long-term biocompatibility and wear resistance. The surface morphology, composition and roughness of uncoated and coated NiTi SMA samples were examined. Energy dispersive X-ray elemental mapping of cross-sections of (Ti, O, N)/Ti coated NiTi SMA revealed that Ni was depleted from the surface of coated samples. No Ni was detected by X-ray photoelectron spectroscopy on the surface of coated samples. Furthermore, three-point bending tests showed that the composite coating could undergo large deformation without cracking or delamination. After 1 day cell culture, SaOS-2 cells on coated samples spread better than those on uncoated NiTi SMA samples. The proliferation of SaOS-2 cells on coated samples was significantly higher at day 3 and day 7 of cell culture. 相似文献
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MengjinLI XiaofengSUN HengrongGUAN XiaoxiaJIANG ZhuangqiHU 《材料科学技术学报》2003,19(3):213-217
(Ni,Pd)Al coating, prepared by low pressure pack cementation on the Ni-base superalloy M38 where Pd-20 wt pct Ni alloy was predeposited, consists of a single β-(Ni,Pd)Al phase. The initial isothermal oxidation behavior of (Ni,Pd)Al coating was investigated by TGA, XRD, SEM/EDS at 800~1100℃. Results show that oxidation kinetics accord preferably with parabolic law at 800, 900 and 1100℃, but not at 1000℃.θ-Al2O3 was observed at 800~1100℃. It is found that Pd plays an important role in accelerating the diffusion of Ti from the substrate to the coating surface in the aluminide coating. 相似文献
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《Vacuum》2013
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. 相似文献
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Fabrication and biocompatibility of polyethyleneimine/heparin self-assembly coating on NiTi alloy 总被引:1,自引:0,他引:1
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. 相似文献
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为了提高2024铝合金的耐磨性,对其进行微弧氧化。利用扫描电镜(SEM)和X射线衍射仪(XRD)分析了涂层的微观组织结构和物相组成;采用高速往复摩擦磨损试验机对2024铝合金微弧氧化涂层在不同载荷下的磨损性能进行了研究,并采用白光三维形貌仪进行磨损形貌分析及磨损体积计算。结果表明:2024铝合金微弧氧化涂层是一种微孔结构,涂层相主要成分为α-Al_2O_3、γ-Al_2O_3,且Al_2O_3具有高硬度、耐磨损的优良特性,有利于提高铝合金的耐磨损性能;微弧氧化涂层的摩擦系数随着载荷的增加而减小,而磨损量随载荷的增加而增加,磨损机理为磨粒磨损。 相似文献
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采用预置粉末式激光熔覆法在钛合金(Ti-6Al-4V)表面开展了Al_2O_3-13%(质量分数)TiO_2涂层的研究。利用光学显微镜(OM)、扫描电子显微镜(SEM)、X射线衍射分析仪(XRD)和显微硬度计研究了激光熔覆熔池的特征和涂层的显微结构,分析了涂层的成分分布、相组成和显微硬度分布情况。预置粉末激光熔覆制备的Al_2O_3-13%(质量分数)TiO_2涂层界面结合良好,涂层组织均匀,没有明显的裂纹和气孔。激光熔覆涂层表现出明显流线型特征,熔覆层截面分为热影响区、扩散结合区和涂层区。涂层由Ti、AlTi_3、α-Al_2O_3和γ-Al_2O_3等相组成。涂层的显微硬度达到1000~1300HV_(0.3),比基体硬度360~390HV_(0.3)高2倍。 相似文献