共查询到20条相似文献,搜索用时 31 毫秒
1.
用溶胶-凝胶法在316L不锈钢及镍钛合金基片上制备含SrFe12O19磁性粉末的TiO2薄膜,分析了膜基的结合强度,并用X射线衍射仪(XRD)、扫描电镜(SEM)等对磁性粉末的表S面结构及形貌进行了分析.动态凝血时间和溶血率的测定结果表明用含磁粉的TiO2薄膜进行表面改性的316L不锈钢和NiTi合金动态凝血时间延长,溶血率下降,证明含磁粉的TiO2薄膜有很好的血液相溶性. 相似文献
2.
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
3.
Zhao T Li Y Gao Y Xiang Y Chen H Zhang T 《Journal of materials science. Materials in medicine》2011,22(10):2311-2318
A composite TiO2/Ta2O5 nano-film has been formed on the NiTi shape memory alloy by Ta implantation. The wettability, protein adsorption, platelets
adhesion and hemolysis tests are conducted to evaluate the hemocompatibility. The contact angle measurements showed that the
surface of the NiTi alloy kept hydrophilic before and after Ta implantation, although the water contact angle increased with
the increasing of implantation current. Both of the surface energy and the interfacial tension decreased after Ta implantation.
The protein adsorption behavior was investigated by 125I isotope labeling. The fibrinogen adsorption was enhanced by a high surface roughness or a large interfacial tension, while
the albumin adsorption was insensitive to the surface modification. Platelet adhesion and activation were weakened and the
hemolysis rate was reduced at least 46% after Ta implantation due to the decreased surface energy and improved corrosion resistance
ability, respectively. 相似文献
4.
5.
Chu CL Wang RM Hu T Yin LH Pu YP Lin PH Dong YS Guo C Chung CY Yeung KW Chu PK 《Journal of materials science. Materials in medicine》2009,20(1):223-228
A dense titania film is fabricated in situ on NiTi shape memory alloy (SMA) by anodic oxidation in a Na2SO4 electrolyte. The microstructure of the titania film and its influence on the biocompatibility of NiTi SMA are investigated
by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry
(ICPMS), hemolysis analysis, and platelet adhesion test. The results indicate that the titania film has a Ni-free zone near
the surface and can effectively block the release of harmful Ni ions from the NiTi substrate in simulated body fluids. Moreover,
the wettability, hemolysis resistance, and thromboresistance of the NiTi sample are improved by this anodic oxidation method. 相似文献
6.
Tao Sun Lang-Ping Wang Min Wang Ho-Wang Tong William W. Lu 《Materials science & engineering. C, Materials for biological applications》2012,32(6):1469-1479
(Ti, O)/Ti, (Ti, N)/Ti and (Ti, O, N)/Ti composite coatings were fabricated on NiTi shape memory alloy via plasma immersion ion implantation and deposition (PIIID). Surface morphology of samples was investigated using atomic force microscopy (AFM) and scanning electron microscopy (SEM). Cross-sectional morphology indicated that the PIIID-formed coatings were dense and uniform. X-ray diffraction (XRD) was used to characterize the phase composition of samples. X-ray photoelectron spectroscopy (XPS) results showed that the surface of coated NiTi SMA samples was Ni-free. Nanoindentation measurements and pin-on-disc tests were carried out to evaluate mechanical properties and wear resistance of coated NiTi SMA, respectively. For the in vitro biological assessment of the composite coatings in terms of cell morphology and cell viability, osteoblast-like SaOS-2 cells and breast cancer MCF-7 cells were cultured on NiTi SMA samples, respectively. SaOS-2 cells attached and spread better on coated NiTi SMA. Viability of MCF-7 cells showed that the PIIID-formed composite coatings were noncytotoxic and coated samples were more biocompatible than uncoated samples. 相似文献
7.
NiTi合金上沉积氮化碳薄膜的力学和血液相容性研究 总被引:1,自引:0,他引:1
采用磁控溅射法在生物医用NiTi合金基体表面制备了Ti/CNx(x≈0.26)梯度薄膜,并制备了Ti/类金刚石(DLC)以及Ti/TiN薄膜进行对比研究. 利用显微硬度计、划痕仪比较分析了上述各薄膜的力学性能,通过表面接触角法研究了薄膜的亲水性. 着重测试并分析了溶血率和血小板粘附行为,进而对薄膜的血液相容性进行评估. 结果表明:Ti/CNx梯度薄膜与NiTi合金基底的结合牢固,结合力达到63.6N. Ti/CNx薄膜硬度为23.01GPa,和Ti/TiN薄膜硬度相当,略高于Ti/DLC薄膜. 溶血率和血小板粘附试验表明,Ti/CNx梯度薄膜能有效改善NiTi合金基底的亲水性和血液相容性,与Ti/TiN和Ti/DLC薄膜相比,Ti/CNx梯度薄膜具有最小的溶血率,仅为1.12%,并且无论在血小板的粘附数量还是在血小板变形程度都最少,因此具有良好的血液相容性. 相似文献
8.
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
9.
C.L. Chu R.M. Wang T. Hu L.H. Yin Y.P. Pu P.H. Lin S.L. Wu C.Y. Chung K.W.K. Yeung Paul K. Chu 《Materials science & engineering. C, Materials for biological applications》2008,28(8):1430-1434
The surface structure and biomedical properties of NiTi shape memory alloy (SMA) samples after undergoing electropolishing and chemical polishing are determined and compared employing scanning electron microscopy, X-ray photoelectron spectroscopy, inductively-coupled plasma mass spectrometry, hemolysis analysis, blood platelet adhesion test, and MTT test. The results indicate that after chemical polishing, there is still a high Ni concentration on the surface of the NiTi SMA. On the other hand, electropolishing can form a thin surface titanium oxide film (about 10 nm thickness) with depleted Ni. In addition to the TiO2 phase, some titanium suboxides (TiO and Ti2O3) are found in the surface film. Compared to chemical polishing, electropolishing can more effectively mitigate out-diffusion of Ni ions and the wettability, blood compatibility, and thromboresistance are also better. However, no difference on the cytocompatibility can be observed from samples that have been chemically polished or electropolished. 相似文献
10.
Tomasz Czeppe Neonila Levintant-Zayonts Zbigniew Swiatek Marek Michalec Olexander Bonchyk Grigorij Savitskij 《Vacuum》2009
This paper reports the application of nitrogen ion implantation for modification of a shape memory alloy. It is known that the problem of creating a protective surface coating for the shape memory alloy is the most acute for potential applications of this material. Thus, the problem of increasing surface protective properties and, at the same time, simultaneous preservation of functional properties of shape memory materials is a subject of research and development [Pelletier H, Muller D, Mille P, Grob J. Surf Coat Technol 2002;158:309.]. The surface characterization of nitrogen implanted (fluence 1018 cm?2 and energy 50 keV) equiatomic commercial NiTi alloy samples was performed with the assistance of high resolution transmission electron microscopy (HTEM) techniques and modifications of phase composition before and after irradiation are studied at room and martensitic transformation temperatures by X-ray diffraction methods. Differential scanning calorimetry (DSC, TA Instruments) was used to characterize the transformation sequence and transformation temperatures for the initial and surface-modified materials. Experimental results of an inhomogeneous structure of near-surface layers in the ion-implanted NiTi alloy are discussed in this paper. 相似文献
11.
Lingamaneni Rama Krishna Yarlagadda Madhavi Thatipamula Sahithi Dameracharla Srinivasa Rao Vijaykumar Sharanappa Ijeri Om Prakash Stephen Paul Gaydos 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(3):698-709
Hard anodized (HA) and micro arc oxidation (MAO) coatings of identical thickness were deposited on two different high strength aluminum (Al) alloys namely, 2024‐T3 and 7075‐T6. Further, as received Al alloys were also subjected to shot peening (SP) to induce subsurface compressive residual stresses followed by the MAO coating deposition (SP + MAO). The average velocity of particle‐in‐flight during the SP process was measured and utilized to calculate the kinetic energy of the peening particles. The bare and coated alloys were subjected to completely reversed stress (R = ?1) rotating beam high cycle fatigue tests at five different stress levels. In addition, the bare and coated alloys were also evaluated for their tensile properties, elemental composition, phase constituents, surface, and cross‐sectional morphologies including the surface roughness (Ra, Rz) and correlated the same with the corresponding fatigue behavior. Irrespective of substrate alloy composition and stress levels investigated, the duplex SP + MAO treatment resulted in significant fatigue life enhancement over and above the fatigue life of corresponding bare (not shot peened) Al alloy, while the hard anodized and plain MAO (both without prior shot peening) continue to exhibit significant fatigue debit. Driven by the compressive residual stresses present beneath the subsurface region of SP + MAO coating interface, fractured surface examination of SP + MAO coatings clearly highlights the crack‐branching associated multiple crack deflection as the predominant operative mechanism responsible for diminishing the crack growth rate and therefore enhance the fatigue life as compared with the near linear crack extension without significant deflections leading to relative premature failure of plain MAO coated alloys. 相似文献
12.
13.
14.
Yu-Hong ZOU Rong-Chang ZENG Qing-Zhao WANG Li-Jun LIU Qian-Qian XU Chuang WANG Zhiwei LIU 《材料科学前沿(英文版)》2016,10(3):281-289
Magnesium alloys as a new class of biomaterials possess biodegradability and biocompatibility in comparison with currently used metal implants. However, their rapid corrosion rates are necessary to be manipulated by appropriate coatings. In this paper, a new attempt was used to develop a zinc-calcium phosphate (Zn-Ca-P) conversion coating on Mg-1.33Li-0.6Ca alloys to increase the biocompatibility and improve the corrosion resistance. In vitro blood biocompatibility of the alloy with and without the Zn-Ca-P coating was investigated to determine its suitability as a degradable medical biomaterial. Blood biocompatibility was assessed from the hemolysis test, the dynamic cruor time test, blood cell count and SEM observation of the platelet adhesion to membrane surface. The results showed that the Zn-Ca-P coating on Mg-1.33Li-0.6Ca alloys had good blood compatibility, which is in accordance with the requirements for medical biomaterials. 相似文献
15.
The martensitic phase transition which produces shape memory is connected with a hysteresis. Some of the applications of shape memory alloys require small hysteresis loops, other require large ones. It is therefore important to be able to control the size of the hysteresis. For that purpose three different methods were introduced in the present paper. Mechanical vibration narrowed the hysteresis loops in both NiTi and CuZnAl alloys by up to 17%, while the width of the hysteresis loops in an NiTi alloy was decreased 3 to 4 times by addition of a third element, copper. With the help of a special heat treatment a nearly hysteresis-free phase transition occurred in a Ti-51 at % Ni alloy. The size of the hysteresis is determined by the interfacial energies of the phase boundaries and these will be big, if the E-modulus and the lattic distortion are big. 相似文献
16.
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
17.
Vladescu A Kiss A Braic M Cotrut CM Drob P Balaceanu M Vasilescu C Braic V 《Journal of nanoscience and nanotechnology》2008,8(2):733-738
In recent years, the smart materials have attracted much attention due to their unusual properties such as shape memory effect and pseudoelasticity, being widely used for biomedical implants. These materials contain certain amounts of nickel, titanium and others which are not adequate for surgical implants and prosthesis. In the work reported here, two types of nonostructured multilayer coatings (TiN/ZrN, ZrN/Zr) used to prevent the ions release from shape memory alloys were investigated. For comparison, the TiN and ZrN monolayers were also examined. The films were deposited onto nickel-titanium based alloy (Ti-Ni-Nb) and Ni substrates by vacuum arc deposition technique under various deposition conditions. The concentrations of dissolved ions in Ringer solution for uncoated and coated Ni samples were determined to examine the benefic barrier effect of these coatings for ions release from shape memory alloys. In order to have a more complete characterization of the investigated coatings, other properties such as elemental and phase composition, morphology, texture, microhardness, and adhesion were studied. For all coatings, the concentrations of dissolved ions were lower that those measured in the case of the uncoated specimens. The nanostructured multilayer films exhibited the best mechanical and anticorrosive properties. 相似文献
18.
Huafang Li Yufeng Zheng Y. T. Pei J. Th. M. De Hosson 《Journal of materials science. Materials in medicine》2014,25(5):1249-1255
This study explores the use of DC magnetron sputtering tungsten thin films for surface modification of TiNi shape memory alloy (SMA) targeting for biomedical applications. SEM, AFM and automatic contact angle meter instrument were used to determine the surface characteristics of the tungsten thin films. The hardness of the TiNi SMA with and without tungsten thin films was measured by nanoindentation tests. It is demonstrated that the tungsten thin films deposited at different magnetron sputtering conditions are characterized by a columnar microstructure and exhibit different surface morphology and roughness. The hardness of the TiNi SMA was improved significantly by tungsten thin films. The ion release, hemolysis rate, cell adhesion and cell proliferation have been investigated by inductively coupled plasma atomic emission spectrometry, CCK-8 assay and alkaline phosphatase activity test. The experimental findings indicate that TiNi SMA coated with tungsten thin film shows a substantial reduction in the release of nickel. Therefore, it has a better in vitro biocompatibility, in particular, reduced hemolysis rate, enhanced cell adhesion and differentiation due to the hydrophilic properties of the tungsten films. 相似文献
19.
针对二元NiTi形状记忆合金在应用中所显示出的局限性,三元NiTi基形状记忆合金通过第三组元的加入,改善了二元NiTi形状记忆合金的某些性能,弥补了其在应用中的不足,降低了成本,进一步扩大了NiTi基形状记忆合金的应用范围,从而一直受到研究者的广泛关注.综述了三元NiTi基形状记忆合金的研究现状,总结了存在的不足:首先,对于合金体系还需要大量的量化研究,确定出不同应用条件下合金的有效成分范围是其实用化的基础;其次,合金制备过程熔炼介质对合金产生的影响等重视不够;同时,应用性能研究还有待加强,性能的长效性与稳定性是关键,这方面的研究还缺乏充分而有效的数据. 相似文献