Electrodeposition of graphene oxide-hydroxyapatite composite coating on titanium substrate

In this work, graphene oxide (GO)/hydroxyapatite (HA) composite coatings were successfully prepared on titanium substrate by electrophoretic deposition technology. Subsequently, microstructure, phase composition, adhesion strength, hydrophilicity, corrosion resistance, bioactivity, antibacterial activity and biocompatibility of the coating were evaluated. The adhesion strength of coating increased by 76% from 6.46 MPa to 17.81 MPa with 0 wt% GO to 12 wt% GO and the corrosion rate of coating with 8 wt% GO was achieved at the minima of (1.493 × 10^-3mm/a). Biomineralization experiment indicated the excellent bioactivity of GO/HA composite coatings. The water contact angle of the composite coatings increased from 20.6°(0 wt% GO) to 38.1°(12 wt%GO). The antibacterial rates of coating with 5 wt% GO was 96.7%, while declined to 25% after thermal treatment. In-vitro L929 cell culture experiments indicated the composite coatings with 5 wt% GO exhibited good biocompatibility.     

Enhancement of mechanical properties of hydroxyapatite coating prepared by electrophoretic deposition method

The addition of bio-inert ceramics such as alumina and zirconia can significantly improve the mechanical properties of hydroxyapatite bioactive coatings and increase their biocompatibility. In the present study, the surface of a titanium substrate was coated by the electrophoretic deposition method (EPD). Moreover, the reaction bonding process has been used to precipitate the nanocomposite containing the hydroxyapatite (HA), alumina, yitteria-stabilized zirconia (YSZ). The coating process was performed by an electrical power supply and a suspension of hydroxyapatite, aluminum, and YSZ nanopowders. For preparing a suspension consisting of 50% isopropanol and 50% acetone, 0.6 g/L of iodine was used as a stabilizer. Green and sintered coatings were analyzed by FE-SEM and XRD. In addition, the mechanical properties such as bonding strength, hardness, and toughness were measured. The hardness, bonding strength, and toughness of the HA coating were 107 ± 10.3 HV, 10.8 ± 3.2MPa, and 0.72MPa√m, respectively, while those of the HA-Al₂O₃-YSZ nanocomposite coating were 213 ± 1.8 HV, 35 ± 1.6MPa, and 1.6MPa√m, respectively.     

钛植入合金表面电化学沉积掺镁羟基磷灰石涂层

以Ca(NO3)2、(NH4)2HPO4和Mg(NO3)2为原料,采用电化学沉积法在医用钛合金表面制备了掺镁羟基磷灰石涂层,研究了电沉积工艺条件对掺镁羟基磷灰石涂层表面形貌的影响。结果表明,当电流密度为1.0mA/cm2,温度为65°C,pH为4.5,n(Mg):n(Ca)=1:3,电沉积时间为1300s时,得到了均匀致密的晶须状涂层。X射线衍射分析表明,烧结后的掺镁羟基磷灰石涂层中Mg2+取代了Ca2+,使HA涂层的晶格发生了变化。     

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...     

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．     

钛合金基磷酸钙涂层的制备及机理研究

使用电结晶法在钛合金表面沉积磷酸钙薄膜 ,使复合材料具有更好的韧性、强度和生物相容性。涂层沉积的最佳条件为Ca(NO3 ) 2 0 .1 0mol/L ,(NH4) 2 HPO40 .0 6mol/L ,电压 2 .5V ,电极间距离 2 5cm ,pH值 4 .4 ,温度 2 5℃ ,沉积时间 5h。强调了pH值是特别重要的因素 ,并分析了沉积的电化学反应机理     

Ni-MoS2梯度复合镀层结合强度研究

在含有NiSO<,4>·6H<,2>O 240 g/L、NiCl<,2>·6H<,2>O 45 g/L、H<,3>BO<,3>30g/L、Na<,2>SO<,4> 20 g/L、CTAB 0.4 mg/L和MoS<,2> 5 g/L的镀液中,通过调整复合电镀参数制备了MoS<,2>梯度复合镀层.研究了不同参数下,所得复...     

电泳涂层花斑浅析

介绍电泳花斑的现象,并分析了造成电泳花斑的影响因素,提出对应的解决方法。     

Electrophoretic deposition of titanium nitride coatings

Electrophoretic deposition of the titanium nitride (TiN) coatings from suspensions prepared by dispersion of TiN particles in triethanolamine (TEA) containing butanol medium was studied. Effects of the TiN particles concentration (C_TiN) on the weight of the deposited coatings, triethanolamine concentration (C_TEA=0.25, 0.5, 0.75, and 1 mL/L) on the Zeta potential of the TiN particles, suspension electrical conductivity and pH, as well as effects of the deposition voltage (V_d=60, 90, and 120 V) and time (t_d =1, 2, and 3 minutes) on the microstructure and thickness of the deposited coatings were investigated. Variations in deposition current density, effective deposition voltage, electrical resistance, and deposited coating weight versus deposition time were recorded. The morphology of the as‐dried coatings was studied using Scanning Electron Microscope (SEM). The results indicated that by increasing the C_TiN the weight of deposits increases linearly up to 40 g/L. For suspensions containing C_TiN=40 g/L, the optimum C_TEA is obtained to be 0.5 mL/L leading to Zeta potential of 43.25 mV. Uniform and crack‐free as‐dried coatings obtained at V_d and t_d of 90 V and 2 minutes, respectively.     

钛合金搪瓷涂层的制备与性能研究

在钛合金表面制备搪瓷涂层,并对其性能进行了研究。结果表明,搪瓷涂层具有较好的抗高温氧化性及抗热震性,能有效提高钛合金的抗腐蚀能力,使其在700°C熔融盐(Na2SO4+NaCl)浸没100h而免遭腐蚀。     

电泳沉积磷灰石生物陶瓷涂层的研究进展

羟基磷灰石(HA)生物涂层材料是最有发展前途的生物硬组织替代材料之一.电泳沉积具有装置简单,操作方便,非线性,沉积温度低等特点,可以解决传统HA生物陶瓷涂层制备工艺上的各种不足.文中探讨了电泳沉积的各种工艺影响因素,综合介绍了国内外有关电泳沉积HA复合(梯度)生物涂层和电泳沉积与其它方法复合制备HA生物涂层的研究报道,进而提出了相应的设想和展望.     

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。     

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.     

Thermal failure of thermal barrier coating with thermal sprayed bond coating on titanium alloy

A thermal spray technology high-velocity oxygen fuel (HVOF) was used to deposit NiCoCrAlY as a bond coating between the titanium alloy substrate and top 8 wt% yttria-stabilized zirconia thermal-barrier coating (TBC) deposited by electron beam-physical vapor deposition (EB-PVD). The thermal cycling and isothermal exposure tests were conducted to evaluate the durability of the TBC. Investigations using OM, SEM, EPMA, and XRD revealed that the thermal-sprayed BC makes the TBC more durable in isothermal exposure tests but more short-lived in thermal cycling tests, in comparison to our previous study in which the BC was prepared by EB-PVD. This is because the thermal-sprayed imperfections, such as microcracks and voids, elevate the diffusion resistance and degrade the mechanical properties of the BC, simultaneously. To current TBC systems in which the BC is deposited by HVOF, thermal failure behaviors—such as the formation of the Ti/Al mixture oxides at some individual places in the BC, and the Ti₂Ni gaps formed around the BC/substrate interface—were also discussed.     

医用钛合金微弧氧化膜的制备及其生物相容性研究

利用微弧氧化技术在Ti合金表面制备了医用羟基磷灰石(HA)膜,研究了HA膜在模拟体液中的生物相容性,通过SEM观察了HA膜在模拟体液中浸泡不同时间的表面形貌,并利用EDs测试了HA膜浸泡前后的Ca、P原子分数.结果表明,HA膜在模拟体液中浸泡后,体液的pH变化不大,而经过溶解-重结晶,新生成的HA晶粒发育更完整,更利于...     

热处理对钛基体表面电泳沉积GO/HA生物活性涂层的影响

采用电泳沉积法在钛基体表面制备氧化石墨烯(GO)/羟基磷灰石(Ca₁₀(PO₄)₆(OH)₂, HA)复合涂层,通过XRD和SEM等测试手段对不同热处理条件下得到的GO/HA涂层进行表征。研究结果表明,热处理有助于促进涂层中HA结晶度的提高,600℃和800℃的热处理温度并没有导致HA发生热分解,但有可能破坏了涂层中GO的有序晶体结构。GO/HA涂层具有优异的生物活性,但随热处理温度的升高,涂层的润湿性和生物活性下降。热处理过程有利于涂层致密,加强涂层与基体的结合,800℃热处理后的涂层结合强度高达25.31 MPa。     

无磷涂装前处理技术在汽车涂装中的应用

介绍了一种节能、环保、低温的无磷涂装前处理新技术.将该技术应用于汽车电泳涂装前处理,所得漆膜的附着力、抗冲击强度和耐腐蚀性能均可满足汽车工业要求,槽液更换周期可由原来的3～4个月延长至8～10个月,操作温度由原来的40～45℃降低到20～30℃.该工艺可共线处理铁板、镀锌板和铝板等多种基材.但是,无磷转化工艺的应用还需要有更高泳透力的电泳漆与之配套,以克服车身漆膜出现的针孔问题.     

丙烯酸树脂电泳涂料

电泳涂料是一种水性涂料 ,具有低污染、节能及高效等优点 ,广泛应用于汽车、轻工、农机、家电、军工、建材等领域。详细介绍了丙烯酸型树脂电泳涂料的阳离子化、典型配方、工艺及发展方向。     

铝合金表面电解沉积稀土转化膜工艺研究

研究了一种通过电解沉积方法在防锈铝LF21表面上生成铈盐转化膜的工艺,应用正交实验研究了有关因素对成膜过程的影响并获得了最佳的技术参数用极化曲线、交流阻抗和中性盐雾试验等方法测试了该工艺形成膜层的耐蚀性能及其组成一结果表明：经过电解沉积稀土转化膜处理后,防锈铝的阳极腐蚀过程受到了阻滞,自然腐蚀电位负移;与经过化学转化膜处理后相比,其耐蚀性能有显著提高,可通过400h的中性盐雾实验,亲水性能亦有明显提高。     

热浸镀锌层表面钛盐转化膜研究

利用钛盐成膜工艺在热镀锌层表面获得了色泽光亮、耐蚀性能优良的银白色转化膜层。采用扫描电镜、能谱仪、电化学极化和盐水浸泡方法研究了钛盐转化膜层的表面形貌、元素组成和耐蚀性能。分析了钛盐溶液成分及工艺参数对热镀锌层表面转化膜的耐蚀性能影响。确定的最佳工艺条件为:Ti(SO4)21g/L,H2O260mL/L,pH0.5～1.0,处理温度25～30°C,处理时间10min。热镀锌层经此工艺处理后,耐蚀性能明显提高。