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1.
Titanium is widely used as an implant material due to its good mechanical properties and the excellent biocompatibility of
the oxide film on the surface. To modify the unstable oxide surface of pure titanium, plasma electrolytic oxidation was applied
in this study. The electrolyte used for anodizing was a mixture of GP (glycerophosphate disodium salt) and CA (calcium acetate).
In addition, a hydrothermal treatment was performed to precipitate a calcium phosphate crystal on the titanium oxide layer
for bioactivity. The effect of the CA concentration of the electrolyte on the surface of titanium was investigated, with CA
concentrations at 0.1 M, 0.2 M, and 0.3 M. A high concentration of CA results in a low breakdown voltage; hence many large
micropores were formed on the anodized surface. Moreover, the size of the HA crystals was more minute in proportion to the
increasing concentration of CA. The crystal phase of titanium dioxide was mainly anatase, and a rutile phase was also observed.
As the size and/or amount of HA crystals increased, the surface roughness increased. However, the surface roughness could
be decreased by fully and uniformly covering the surface with HA crystals. The corrosion resistance in the saline solution
was increased by anodic spark oxidation. In addition, it was slightly increased by a hydrothermal treatment. It is considered
that a more stable and thicker titanium oxide layer is formed by anodic oxidation and a hydrothermal treatment. 相似文献
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Il Song Park Jong Jun Kim Seung Geun Ahn Min Ho Lee Kyeong Won Seol Tae Sung Bae 《Metals and Materials International》2007,13(2):117-122
This study examined the effect of fluoride on the surface characteristics of an anodized titanium implant. Commercial pure
titanium plate 20mm×10mm×2mm in size, and discs 1.5 mm thick and 1.5 mm in diameter, were used. The prepared samples were
polished with #200 to #1, 000 SiC papers and were then washed sequentially with distilled water, alcohol and acetone. Anodic
oxidation was performed using a regulated DC power supply in an electrolyte containing a mixture of 0.015 M DL-α-glycerophosphate
disodium salt hydrate (DL-α-GP) and 0.2 M calcium acetate hydrate (CA) with an electric current density of 30mA/cm2 and voltage ranging from 0 to 290 V. The specimens were divided into four groups and a fluoride treatment was carried out.
Group 1 was thermally treated in a 0.05 M TiF3 solution at 90°C, Group 2 was electrochemically treated at 150 V in a 0.05 M TiF3 solution, Group 3 was electrochemically treated at 150 V in a 0.05 M NaF solution, and Group 4 was electrochemically treated
at 150 V in a 0.05 M HF solution. A porous oxide layer containing pores 1–4 μm in size was observed on the surface treated
with anodic oxidation. The diameter of the pores was higher in the protrusion areas than in the sunken areas. A significant
amount of fluoride ions was released in the initial period, with small amounts being released continuously thereafter. The
viability of MC3T3 cells was high when the fluoride ion concentration was 10 ppm, but decreased with further increases in
the fluoride concentration. A six-week immersion test in simulated body fluid (SBF) showed dense HA crystals in the group
immersed in 0.05 M TiF3 at 90°C, which indicated good biocompatibility. 相似文献
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In order to overcome the poor osteo-inductive properties of titanium implant, some methods have been used. The efforts to improve implant biocompatibility and durability by applying a hybrid technique of composite oxidation (pre-anodic and micro-arc oxidation) and hydrothermal treatment were described. Pure titanium was used as the substrate material. An oxalic acid was used as the electrolyte for the pre-anodic oxidation. A calcium and phosphate salt solution was acted as the electrolyte of micro-arc oxidation and the common pure water was used for hydrothermal treatment. X-ray diffraction (XRD), and scanning electron microscopy (SEM) have been used to investigate the microstructure and morphology of the coatings. The results show that a compact TiO2 film can be made by pre-anodic oxidation, which is effective as chemical barriers against the in-vivo release of metal ions from the implants. A porous TiO2 coating can be produced by micro-arc oxidation on titanium plate, which is beneficial to bone tissue growth and enhancing anchorage of implant to bone. De-calcium HA can be formed on the coating using hydrothermal treatment, which is similar with the primary component of bone and has a very good osteo-inductivity.The porous gradient titania coating made by the hybrid oxidation and hydrothermal treatment should show good biocompatibility in the environment of the human body. 相似文献
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1 Introduction Titanium implants have been used widely for various types of bone-anchored reconstructions due to their excellent corrosion resistance and mechanical properties. However, titanium exhibits poor osteoinductive properties, fortunately, which… 相似文献
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Hydroxyapatite(HA) coating has been prepared on titanium substrate through an electrochemical deposition approach. In order to improve the bonding strength between HA coating and Ti substrate, a well oriented and uniform titanium oxide nanotube array on the surface of titanium substrate was applied by means of anodic oxidation pre-treatment. Then the calcium hydrogen phosphate(CaHPO4·2H2O, DCPD) coating, as the precursor of hydroxyapatite coating, was electrodeposited on the anodized Ti. At the initial stage of electro-deposition, the DCPD crystals, in nanometer precipitates, are anchored in and between the tubes. With increasing the deposition time, the nanometer DCPD crystals are connected together to form a continuous coating on titanium oxide nanotube array. Finally, the DCPD coating is converted into hydroxyapatite one simply by being immersed in alkaline solution. 相似文献
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电化学沉积法制备钛基HA涂层 总被引:5,自引:0,他引:5
在钛基材表面获得羟基磷灰石(HA)涂层以改善钛与生物体的相容性,本项工作采用电沉积的方法在阳极氧化处理过的钛基体上制备了羟基磷灰石涂层。用扫描电子显微镜(SEM)、X射线衍射(XRD)等手段对涂层进行了表征。试验结果表明:电沉积初期的羟基磷灰石涂层呈多孔层片状:随电压、时间、电解液浓度的增大,涂层变厚,层片呈花瓣状发散排列:对基体阳极氧化处理有助于提高钛基与涂层的结合强度。 相似文献
8.
A porous cerium-containing hydroxyapatite coating on commercially pure titanium was prepared by micro-arc oxidation (MAO) in an electrolytic solution containing calcium acetate, p-glycerol phosphate disodium salt pentahydrate (β-GP), and cerium nitrate. The thickness, phase, composition morphology, and biocompatibility of the oxide coating were characterized by X-ray diffraction (XRD), electron probe microanalysis (EPMA), scanning electron microscopy (SEM) with energy dispersive X-ray spectrometer (EDS), and cell culture. The thickness of the MAO film is about 15-25 ~tm, and the coating is porous and uneven, without any apparent interface to the titanium substrates. The results of XRD and EDS show that the porous coating is made up of hydroxyapatite (HA) film containing Ce. The favorable osteoblast cell affinity makes the Ce-HA film have a good biocompatibility. The Ce-HA film is expected to have significant medical applications as dental implants and artificial bone joints. 相似文献
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应用电化学阳极氧化方法,在自选的电解液中,通过调节氧化电压和氧化次数制备不同管径的TiO2纳米管。其管径可分别控制在50,100和200nm左右。其中50和100nm范围的纳米管是一次氧化所制得。通过再次氧化突破了一次氧化对尺寸的限制,所制得纳米管的最大管径达到280nm。实验证实,在一定的电压范围内,通过调节阳极氧化的电压可以控制TiO2纳米管的管径大小。但是,在本实验的电解液条件下,在一次氧化过程,通过调节电压制备出的纳米管最大管径只能达到120nm。采用两次氧化能将TiO2纳米管的管径扩大到更大的尺寸,可以扩展TiO2纳米管的应用范围。 相似文献
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为了提高Ti-6Al-4V钛合金表面的生物活性,在乙酸钙和磷酸二氢钠溶液中对Ti-6Al-4V钛合金进行微弧氧化,研究氧化时间,电压,占空比等对氧化膜厚度及其表面形态的影响。结果表明,在一定条件下,随氧化时间的增加,氧化膜厚度以指数关系增加,而膜层表面孔洞逐渐变小,最终封闭;随着电压的提高,膜层厚度增加平缓,但电压过大时,膜层反而变薄,氧化膜表面微孔的数量减少,但微孔的孔径逐渐增大;占空比的提高使得膜层厚度增加,同时伴随有膜层孔洞分布的均匀性变差,表面粗糙度增加。 相似文献
14.
T Matsubara 《稀有金属材料与工程》2012,(Z1):38-42
Hot water treatment was performed to modify the surface of porous TiO2 layer prepared by anodic spark oxidation technique for better biocompatibility.The oxide layer without water treatment exhibited a porous surface with few nanometer features and consisted of poorly crystallized oxides.During water treatment,the poorly crystallized oxides were transformed into crystalline anatase gradually and numerous nanoparticles formed on the oxide surface,leading to increased surface roughness at the nanoscale.The indentation deformation behaviors of oxide layer before and after water treatment were investigated and compared.Results show that under the indentation load,the untreated anodic TiO2 layer exhibited good adhesion to the substrate.In contrast,after water treatment,apparent oxides pile-up and spallation were observed around the indentation,indicating decreased adhesion strength. 相似文献
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To improve the erosion resistance of titanium, several surface treatment methods were applied: (1) duplex treatment with carbon
nitride film deposited on a plasma-nitrided layer, (2) diamond coating, and (3) laser alloying. Duplex treatment could improve
the erosion resistance of titanium under a low impact velocity of erosion particles. However, under a high velocity of erosion
particles, because of the shallow depth of the plasma-nitrided layer and low load-bearing capacity of carbon nitride layer
on the plasma-nitrided specimen, the improvement of erosion resistance was not significant. Diamond coatings with a thickness
of 15 μm made no significant improvement on the erosion resistance of the titanium substrate. The large-area spallation of diamond
coating during erosion was observed, probably due to the high residual stresses, poor load-bearing capacity, and brittle nature
of diamond coatings. Compared with untreated Ti substrate, the erosion resistance of the laser-alloyed (nitrided) specimen
was improved significantly. The erosion mechanisms for laser-nitrided titanium were characterized by chipping, brittle fracture,
and formation of large flakes in the laser-nitrided layers. 相似文献
17.
L. C. Tsao 《腐蚀工程科学与技术》2018,53(8):582-590
The effects of the applied voltage on the morphology, composition and corrosion behaviour of Ti7Cu5Sn coated were investigated. At applied voltages lower than 250?V, the composite coatings consist of anatase-TiO2, rutile-TiO2, DCPD(CaHPO4·2H2O) and a small amount of amorphous calcium phosphate phase. When the applied voltage is increased, the ceramic coatings transform from DCPD (CaHPO4·2H2O) to HA (Ca10(PO4)6(OH)2, 300?V), and new phases of Ca2P2O7, CaTiO3 and TCP(Ca3(PO4)2) form at 350?V. The passive current densities at body potential are one order of magnitude lower than that of the uncoated sample, indicating better corrosion resistance. The MAO film is a tri-layer system: a compact inner layer, a mesosphere porous oxide layer, and an outer layer. 相似文献
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采用微弧氧化处理技术,在纯钛TA2表面制备了含钙磷的多孔复合氧化膜,用SEM、XRD、EPMA等分析了电解液成分对氧化膜形貌、成分、相构成及生物活性的影响。结果表明:纯钛表面微弧氧化后原位生成的含钙磷多孔性复合氧化膜由锐钛矿相TiO2,金红石相TiO2和基体Ti组成;随电解液中钙磷摩尔比(Ca/P)值的增大,表面孔洞数量增多、直径变小,膜中Ca/P值增大,锐钛矿相TiO2减少、金红石相TiO2增多;当电解液中Ca/P=5时得到的氧化膜的Ca/P值为1.528,将该样品经碱液处理后再在快速钙化溶液(FCS)中浸泡2 d后即有羟基磷灰石HA形成,表明其具有良好的生物活性。 相似文献