在钛基上电泳沉积羟基磷灰石生物陶瓷涂层的研究

将羟基磷灰石(HAP)电泳沉积在钛基材上，得到了结构稳定的HAP生物陶瓷涂层。研究了电场强度、悬浮液温度、电泳时间、分散介质及HAP浓度对涂层形貌的影响。通过红外光谱仪(FTIR)和X射线衍射仪(XRD)对涂层的组成及结构进行了分析，并采用扫描电镜(SEM)对涂层煅烧前后的微观形貌进行了观察。结果表明：在正丁醇作为分散剂、悬浮液温度30℃、电场强度250V／cm、电泳时间300s以及HAP浓度5．0g／L的条件下可制得形貌较好的HAP生物陶瓷涂层；经二次电泳沉积及煅烧后得到的HAP生物陶瓷涂层均匀致密．     

Yttria-stabilized zirconia closed end tubes prepared by electrophoretic deposition

The electrophoretic deposition technique was used for the preparation of ZrO₂:8 mol% Y₂O₃ (yttria-stabilized zirconia, 8YSZ) closed end tubes for application in high temperature oxygen sensing devices. The 8YSZ ceramic suspensions with different average particle sizes were investigated looking for the best conditions for electrophoretic deposition of thin wall closed end ceramic tubes. High deposition rate of the ceramic particles onto graphite were obtained with isopropanol as solvent and 4-hydroxybenzoic acid as dispersant, with good surface quality of the deposited layer. The green tubes were dried and sintered at 1500 °C, and their properties were analyzed by X-ray diffraction for determination of the structural phases, scanning probe microscopy for observation of grain morphology, and impedance spectroscopy for evaluation of the oxide ion electrical resistivity. Pt/YSZ tube/Pt electrochemical cells were assembled for exposure to oxygen in the 60-650 ppm range using an electrochemical YSZ oxygen pump and sensor system. The signal response of the electrophoretic deposited sensor was similar to the response of the sensor of the oxygen pump. Several thin wall 4 mm diameter × 30 mm length closed end tubes may be obtained in a single operation, showing the ability of this technique for processing large quantities of tubular solid electrolytes with electrical properties suitable for use in high temperature devices.     

Electrodeposition of fluorohydroxyapatite gradient coating on titanium alloy

In order to obtain the apatite implants which can meet the requirements for both bonding strength and bioactivity, the FHA(Ca₁₀(PO₄)₆OH_2−xF_x(x = 0 ~ 2)) gradient coating was prepared by electrophoretic deposition on the surface of titanium alloy (Ti–6Al–4V). The effects of fluorine substitution and gradient structure on the morphology, bonding strength, and bioactivity of the coating were investigated. The gradient coating has the dense inner layer and porous outer layer that were deposited by controlling the suspension concentration and the preparation process. Through controlling of the fluorine substitution gradient, the thermal expansion coefficient gradually changed to improve the bonding strength more than 30 Mpa. The inner layer with high fluorine content can improve the thermal stability of the coating and bonding strength between the coating and the substrate, while the proper content of fluorine in the outer layer improves the bioactivity of the gradient coating.     

硝酸盐对电泳沉积钛基石墨烯冷阴极场发射性能的影响

采用电泳沉积的方法在金属钛片衬底上制备石墨烯冷阴极。研究了Mg(NO3)2·6H2O、Zn(NO3)2·6H2O和Al(NO3)3·9H2O对石墨烯冷阴极表面形貌、成分以及场发射性能的影响。用原子力显微镜(AFM)对自制氧化石墨烯的尺寸和厚度进行了表征,用扫描电镜(SEM)和傅里叶变换红外光谱(FT-IR)分析了石墨烯冷阴极表面的结构和组成。场发射测试结果表明:不同的硝酸盐对电泳制备的石墨烯冷阴极的场发射性能产生了影响。采用Mg(NO3)2·6H2O时,所得的石墨烯冷阴极场发射性能最好,开启场为3.3 V/μm,阈值场为6.3 V/μm。     

Structural characterization of YSZ/Al2O3 nanostructured composite coating fabricated by electrophoretic deposition and reaction bonding

Suspension of YSZ and Al particles in acetone in presence of 1.2 g/l iodine as dispersant was used for electrophoretic deposition of green form YSZ/Al coating. Results revealed that applied voltage of 6 V and deposition time of 3 min were appropriate for deposition of green composite form coating. After deposition, a nanostructured dense YSZ/Al₂O₃ composite coating was fabricated by oxidation of Al particles at 600 °C for 2 h and subsequently sintering heat treatment at 1000 °C for 2 h. Melting and oxidation of Al particles in the green form composite coating not only caused reaction bonding between the particles but also lowered the sintering temperature of the ceramic coating about 200 °C. The EDS maps confirmed that the composition of fabricated coating was uniform and Al₂O₃ particles were dispersed homogenously in YSZ matrix.     

阴极电泳涂装设备的改进及工艺维护

阴极电泳涂装具有很多优点，如涂膜均匀、致密、延展性、外观和耐蚀性好，成本低、生产效率高，在国内外已广泛用于金属表面处理。根据多年生产实践的经验，针对原有阴极电泳涂装设备所存在的缺点，对挂具、超滤装置、烘干设备、电源和循环装置等进行改进。另外，介绍了阴极电泳涂装生产的工艺维护。     

Particle size separation by alternating electrophoretic deposition

This paper describes a study of the size distribution of the particles deposited under different frequencies by alternating electrophoretic deposition. A low concentration suspension of SnO₂ particles was prepared in acetone and particles of SnO₂ were deposited on electrodes by the low frequency alternating electrophoretic deposition method. Scanning electron microscopy (SEM) showed that increasing the frequency from 0 to 1000 Hz reduces the average size of the SnO₂ particles deposited. Particle size distributions obtained from the SEM images show the sizing capability of the alternating electrophoretic deposition method.     

脉冲电沉积纳米镍-碳化硅复合镀层的性能

分别采用直流(DC)和换向脉冲电流(PRC)电沉积法制得纳米Ni-SiC复合镀层。采用X射线衍射仪、扫描电镜、能谱仪对比研究了纯Ni镀层和Ni-SiC复合镀层的微观结构、宏观残余应力、表面形貌及成分。用浸泡法研究了不同镀层在3.5%(质量分数)NaCl和10%(体积分数)H2SO4溶液中的腐蚀行为。结果表明,脉冲电沉积能改变镀层的微观结构,有效提高镀层硬度,降低宏观残余应力。脉冲电沉积所得到的纯Ni镀层和纳米Ni-SiC复合镀层在3.5%NaCl及10%H2SO4溶液中的耐蚀性均优于直流镀层。脉冲镀层在3.5%NaCl溶液中受腐蚀很轻,主要腐蚀形态为点蚀,而在10%H2SO4溶液中,SiC粒子作为增强相使镀层的耐腐蚀性进一步提高。     

阴极聚氨酯电泳涂料的漆膜性能研究

以甲苯二异氰酸酯(TDI)、聚合物多元醇(PEA)、亲水剂(MDEA)以及封端剂通过丁酮法合成了阳离子型水性聚氨酯电泳涂料。实验结果表明：亲水剂用量越多，耐水性越差；交联剂用量越多，乳液的柱径越小，粘度越大，漆膜的硬度越高，耐水性越好；离子化试剂的用量越少，耐水性越好，但硬度降低；DSC结果表明丙二酸二乙酯封端的PU漆膜的分解温度为128℃，漆膜的耐水性大于96h，铅笔硬度4H。     

Fabrication and characterization of carbon-based counter electrodes prepared by electrophoretic deposition for dye-sensitized solar cells

Three different carbon-based counter electrodes are investigated in light of catalytic activities such as electrochemical frequencies and interface impedances. We fabricated carbon-based counter electrodes of dye-sensitized solar cells [DSSCs] using graphene, single-walled carbon nanotubes [SWNTs], and graphene-SWNT composites by electrophoretic deposition method. We observed the optical and electrochemical properties of the carbon-based counter electrodes. The DSSC with the graphene-deposited counter electrode demonstrated the best conversion efficiency of 5.87% under AM 1.5 and 1 sun condition. It could be utilized for a low-cost and high-throughput process for DSSCs.     

单组分丙烯酸阴极电泳涂料的研制

阴极电泳涂料由于其优异的耐蚀性能、高的泳透力和库仓效率而广泛用作防锈底漆。在此采用封闭不饱和异氰酸酯与常用的丙烯酸酯类单体共聚制备单组分丙烯酸阴极电泳涂料。探讨了合成树脂的配方及反应条件 ,并对所得阴极电泳涂料的性能进行了测试。该阴极电泳涂料克服了外加交联剂固化电泳涂料的缺点 ,具有可着色性、高耐蚀性和装饰性等优点。     

基于电泳沉积工艺的低粘附抗菌涂层的制备

低表面能涂层因其优异的防污自清洁能力而受到广泛关注,但现有涂层存在易被细菌和真菌等微生物破坏而导致防污效果下降的问题,因此构建防污抗菌涂层具有深远的意义。本文基于电泳沉积工艺,将乙烯基硅油改性聚丙烯酸酯和固化剂沉积到导电基底,进一步负载纳米银杀菌剂,经过交联固化后获得了兼具抗细菌粘附与杀菌功能的涂层。采用傅里叶变换红外光谱仪(FT-IR)、核磁共振波谱仪(NMR)和扫描电子显微镜(SEM)等对涂层的结构和形貌进行了系统的表征,结果表明,成功合成了兼具低粘附与杀菌功能涂层。涂层表面具有优异的防油污、细菌及血液粘附的能力,涂层对大肠杆菌和金黄色葡萄球菌的抗细菌粘附效果达到99.9%以上。即使经过强酸、强碱等极端环境以及摩擦3000次后,涂层表面仍具有优异的防液体粘附效果。     

The synergistic effect of texture and surface roughness on electrophoretic deposited bioactive glass coating

To improve the biocompatibility of AISI 316L, bioactive glass (BG) coating of SiO₂–CaO–P₂O₅ which helps bonding with bone implants was used by an electrophoretic deposition method. Before coating deposition, the samples were treated by shot peening, known as an efficient process for metal grain refinement and fatigue properties. The stainless steel 316L was investigated in terms of microstructure, texture, and roughness. This research covers the effects of chosen shot peening parameter on the BG-coating properties on the obtained results. Shot peening was carried using two different sets of parameters as conventional shot peening, and severe shot peening. Wettability, roughness, microstructure, coating thickness, and corrosion behavior of coated sample were investigated in terms of potentiodynamic polarization and electrochemical impedance spectroscopy in simulated body fluid (SBF) solutions at 37°C. The results indicated that the coating thickness decreased from 35.5 ± 10 µm for coated not peened (CNP) to 20 ± 5 and 17 ± 2 µm for coated conventionally shot-peened (CCSP) and coated severely shot-peened (CSSP), respectively. As well as, the water contact angle of CSSP sample was equal to 15.71° which is much lower than CNP (20.7°). The protection ability of the tested samples in the SBF was improved in the following order: CCSP < CNP < CSSP.     

Controlling the degradation rate of bioactive magnesium implants by electrophoretic deposition of akermanite coating

In order to improve the corrosion resistance and the surface bioactivity of biodegradable magnesium alloys, a nanostructured akermanite (Ca₂MgSi₂O₇) coating was grown on AZ91 magnesium alloy through electrophoretic deposition (EPD) assisted with micro arc oxidation (MAO) method. The crystalline structures, morphologies and compositions of samples were characterized by X–ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The in vitro bio–corrosion (biodegradability) and bioactivity behaviors of samples were investigated by electrochemical and immersion tests. The experimental results indicated that the nanostructured akermanite coating could slow down the corrosion rate and improve the in vitro bioactivity of biodegradable magnesium alloy. Thus, magnesium alloy coated with nanostructured akermanite may be a promising candidate to be used as biodegradable bone implants.     

Characterization of hydroxyapatite-tantalum pentoxide nanocomposite coating applied by electrophoretic deposition on Nitinol superelastic alloy

In this study, natural hydroxyapatite (nHA) and nHA-20?wt.%Ta₂O₅ nanocomposite coatings were deposited via electrophoretic deposition (EPD) on the NiTi substrate. The suspensions of nHA and nHA-Ta₂O₅ nanoparticles were prepared in n-butanol as a medium with different contents (0, 4, 8, 12, 16, and 20?mL/L) of triethanolamine (TEA) as a dispersant. The most stable suspensions of nHA and nHA-Ta₂O₅ nanoparticles were achieved with 16?mL/L TEA according to the sedimentation test and zeta potential measurement results. The enhanced colloidal stability of nanoparticles in n-butanol by TEA addition was investigated by FTIR analysis. The highest in-situ EPD kinetics were accomplished from suspensions containing an optimum concentration of dispersant. The phase compositions and microstructures of the coatings, before and after sintering under 1.4?×?10^?6?mbar vacuum at 800?°C for 1?h, were perused using XRD and FESEM, respectively. The results of the nano-scratch analysis showed the highest critical distance of delamination (0.38?mm), normal load before failure (133?mN) as well as the critical contact pressure (7.12?GPa) for nHA-Ta₂O₅ coating on the NiTi. The concentration of the released Ni ions from passivated-NiTi with nHA coating in PBS after 30 days of immersion reduced from 45.72 to 5.62 μg/Lcm² by introducing Ta₂O₅ in nHA matrix. On the other hand, the improved corrosion behavior of passivated-NiTi with nHA-Ta₂O₅ coating in comparison to that of with nHA deposit was explained with the lower amount of open porosities in the microstructure. The biocompatibility of the nHA and nHA-Ta₂O₅ surfaces were studied by osteoblast cell attachment during 7 days of culturing.     

Microstructure and mechanical properties of yttria stabilized zirconia coatings prepared by plasma spray physical vapor deposition

Plasma spray physical vapor deposition (PS-PVD) was used to deposit yttria stabilized zirconia (YSZ) coatings with different columnar morphologies by varying the spray distance. Although similar quasi-columnar structures were formed at the spray distances of 600 mm and 1400 mm, the formation mechanisms of particles in the coatings were different. Besides, an electron beam physical vapor deposition (EB-PVD) like columnar coating out of pure vapor was deposited at a spray distance of 1000 mm and the columnar consisted of elongated nano-sized secondary columns. The hardness and Young׳s modulus of the coatings were investigated. Compared to the other two quasi-columnar structures, the EB-PVD like columnar coating exhibited higher hardness (~9.0 GPa ) and Young׳s modulus (~110.9 GPa), mainly due to its low porosity and defect.     

医用钛合金表面羟基磷灰石/二氧化锆梯度复合涂层的制备

用恒电流沉积方法分别在ZrO(NO3)2电解液和由Ca(NO3)2及NH4H2PO4组成的电解液中制备出羟基磷灰石/二氧化锆(HA/ZrO2)梯度医用复合涂层.通过扫描电镜观察,研究了沉积电流和沉积时间对涂层形貌的影响.结果表明,当沉积电流为11.1 mA,沉积时间为400 s时,在锆电解液中可获得均匀的钛基Zr(OH...     

Enhancement of the microwave absorption properties of PyC-SiCf/SiC composites by electrophoretic deposition of SiC nanowires on SiC fibers

The employment of coating technique on the silicon carbide fibers plays a pivotal role in preparing SiC fiber-reinforced SiC composites (SiC_f/SiC) toward electromagnetic wave absorption applications. In this work, SiC nanowires (SiCNWs) are successfully deposited onto the pyrolytic carbon (PyC) coated SiC fibers by an electrophoretic deposition method, and subsequently densified by chemical vapor infiltration to obtain SiCNWs/PyC-SiC_f/SiC composites. The results reveal that the introduction of SiCNWs could markedly enhance the microwave absorption properties of PyC-SiC_f/SiC composites. Owing to the increasing of SiCNWs loading, the minimum reflection loss of composites raises up to −58.5 dB in the SiCNWs/PyC-SiC_f/SiC composites with an effective absorption bandwidth (reflection loss ≤ −10 dB) of 6.13 GHz. The remarkable enhancement of electromagnetic wave absorption performances is mainly attributed to the improved dielectric loss ability, impedance matching and multiple reflections. This work provides a novel strategy in preparing SiC_f/SiC composites with excellent electromagnetic wave absorption properties.     

电泳沉积法制备高能量密度的非对称平面微型超级电容器

首先采用光刻、蒸镀金的方法制备叉指电极,随后把合成的具有赝电容特性的二维MnO2和Ti3C2纳米片分别电泳沉积到叉指电极上,构建了非对称平面超级电容器.其中MnO2为正极,Ti3C2为负极,滴涂凝胶为电解质,并利用透明的聚二甲基硅氧烷薄膜封装成器件.通过能量色散X射线光谱(EDS)、傅里叶变换红外光谱(FT-IR)、扫...     

低温固化环氧阴极电泳涂料的制备

采用乙二醇单丁醚和甲乙酮肟对甲苯二异氰酸酯(TDI)进行全封闭,并将其加入到二乙醇胺改性的环氧树脂乳液中进行混合搅拌,制备了一种低温固化环氧阴极电泳涂料。研究了封闭反应温度、TDI用量和接枝反应温度对漆膜性能的影响,确定了适宜的工艺条件:甲乙酮肟封闭反应温度为40°C,接枝反应温度80°C,TDI质量分数为15%左右。在此条件下制备的漆膜可以在150°C/30min的条件下固化,所得漆膜厚度20μm,光泽70°,附着力1级,柔韧性1mm,铅笔硬度3H,冲击强度>50kg.cm,耐水性>800h,达到设计要求。