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采用化学镀技术,实现了芳纶纤维表面化学镀Ni-P/Ni-Cu-P的金属化处理,利用SEM、EDS和XRD分别对芳纶纤维原始样品、粗化后、施镀后及剥落层的表面形貌、镀层的成分和物相进行了分析比较,并对镀层的形成机制及剥落原因进行了分析研究。结果表明:经过预处理的芳纶纤维比表面积增大,增加了其亲水性和活性;化学镀Ni-P/Ni-Cu-P后,Ni-P镀层中镍含量降低,磷含量增多,纯镍转化为Ni3P且伴随有少量的铜的出现,整体镀层中Ni、Cu、P的原子比为8.54:3.66:5.59,镀层中以纯Cu、Cu3P和Ni3P为主;另外由于镀层中应力分布不均,以及P在Ni-P/Ni-Cu-P相界面的偏聚,削弱了界面的结合强度,使局部拉应力集中,造成了镀层的剥落;且化学镀铜是依靠镍离子的催化作用形成镀层的。 相似文献
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J.N. Balaraju V. Ezhil Selvi V.K. William Grips K.S. Rajam 《Electrochimica acta》2006,52(3):1064-1074
The autocatalytic (electroless) deposition of Ni-P based alloys is a well-known commercial process that has found numerous applications because of their excellent anticorrosive, wear, magnetic, solderable properties, etc. It is a barrier coating, protecting the substrate by sealing it off from the corrosive environments, rather than by sacrificial action. The corrosion resistance varies with the phosphorus content of the deposit: relatively high for a high-phosphorus electroless nickel deposit but low for a low-phosphorus electroless nickel deposit. In the present investigation ternary Ni-W-P alloy films were prepared using alkaline citrate-based bath. Quaternary Ni-W-Cu-P films were deposited by the addition of 3 mM copper ions in ternary Ni-W-P bath. X-ray diffraction (XRD) studies indicated that all the deposits were nanocrystalline, i.e. 1.2, 2.1 and 6.0 nm, respectively, for binary, ternary and quaternary alloys. Corrosion resistance of the films was evaluated in 3.5% sodium chloride solution in non-deaerated and deaerated conditions by potentiodynamic polarization and electrochemical impedance (EIS) methods. Lower corrosion current density values were obtained for the coatings tested in deaerated condition. EIS studies showed that higher charge transfer resistance values were obtained for binary Ni-P coatings compared to ternary or quaternary coatings. For all the coatings a gradual increase in the anodic current density had been observed beyond 740 mV. In deaerated condition all the reported coatings exhibited a narrow passive region and all the values of Ep, Etp and ipass were very close showing no major changes in the electrochemical behavior. In the non-deaerated conditions no passivation behavior had been observed for all these coatings. 相似文献
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Ni-P化学镀层正交实验设计及形貌结构分析 总被引:6,自引:0,他引:6
在温度、pH、装载比、施镀时间和复合添加剂的质量浓度一定的条件下,通过正交实验和单因素实验研究了镀液中硫酸镍、次磷酸钠、柠檬酸钠和硼酸的质量浓度对镀层沉积速度和镀层表面质量的影响,获得了最佳工艺参数:ρ(硫酸镍)30 g/L,ρ(次磷酸钠)20 g/L,ρ(柠檬酸钠)25 g/L,ρ(硼酸)38 g/L,ρ(复合添加剂)15 mg/L,温度(85±1)℃,装载比1.5 dm2/L,pH 9,沉积时间1~1.5 h。金相照片显示,N i-P化学镀层表面由均匀的胞状颗粒组成,镀层致密,无空隙;镀层截面照片和300℃热震实验表明,镀层与基体结合力良好;EDS和X-射线衍射图谱证明合金镀层中P的质量分数为10.85%,镀层呈非晶态结构。 相似文献
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采用电化学阻抗谱(EIS)研究了无机富锌底漆/环氧云铁中间漆/氯化橡胶面漆复合涂层体系在3.5%NaCl溶液中的腐蚀电化学行为,考察了紫外辐射对其电化学行为的影响。结果表明:复合涂层体系在3.5%NaCl介质中的腐蚀失效过程可以用4种等效电路来等效。浸泡失效前120 h,电解质溶液电阻Rc从开始的5×109 Ω·cm2以大约2.2×107 Ω·h-1的速度迅速下降到4×105 Ω·cm2,到浸泡120 h后Rc则以较小的速度808 Ω·h-1下降,涂层电容Cc是按线性增加。紫外辐射不改变复合涂层体系在3.5% NaCl溶液中的电化学行为,仅仅加速复合涂层的失效。 相似文献
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The effect of gluconate on the deposition rate and the deposit composition was examined at low pH of solution. The deposition rate exhibit a maximum and the content of copper present a minimum when the gluconate concentration changes between 0 and 40 g/l. The kinetic study carried out by cyclic voltammetry and electrochemical impedance showed that the gluconate acts on the anodic and cathodic reactions. The activation energy of the alloy deposition was determined. In addition, gluconate does not affect the crystallinity of the Ni-Cu-P deposit. 相似文献
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Ni-P化学镀层换热器应用动向 总被引:3,自引:0,他引:3
化学镀Ni-P镀层换热器在石化行业近年得到一定的工业应用,但由于工艺控制等原因,镀层具有孔隙,影响使用,采用镀后化学处理及涂数有机涂层等,能使换热器是一步提高。 相似文献
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采用极化曲线和交流阻抗法,与Ni-P合金镀层对比,研究了化学镀Ni-Cu-P合金镀层在3.5%NaCl水溶液中的电化学行为。极化曲线结果表明,化学镀Ni-Cu-P合金镀层的自腐蚀电流密度(4.037μA/cm2)远远小于Ni-P合金镀层,说明Ni-Cu-P合金镀层的耐蚀性能比Ni-P合金镀层好。在交流阻抗谱图中,化学镀Ni-Cu-P合金镀层在整个浸泡过程中仅出现一个时间常数的单容抗弧,镀层电阻不断的增大,表明镀层有钝化膜不断生成。 相似文献
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在中温酸性条件下用化学沉积方法制备了Ni-Cu-P合金镀层,采用扫描电镜、能谱分析仪及Autolab工作站研究了镀层的耐蚀性能,确定了化学镀Ni-Cu-P合金的最佳工艺。其最佳工艺为:25 g/L NiSO_4·6H_2O,0.05 g/L CuSO_4·5H_2O,40 g/L C_6H_5Na_3O_7·2H_2O,25 g/L NaH_2PO_2·H_2O、15 g/L CH_3COONa,0.03 g/L KIO_3,0.01 g/L C_(12)H_(25)NaO_4SO_3,pH为(4.75±0.01),θ为(80±1)℃,沉积t为2 h。研究结果显示,中温酸性化学镀Ni-Cu-P合金镀层的腐蚀电流密度明显低于化学镀镍-磷合金镀层以及基体材料的腐蚀电流密度,其耐蚀性得到显著提高。 相似文献
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在AZ 91D镁合金基体上分别制备三元化学镀Ni-Cu-P,Ni-Ce-P镀层,用失重法将试样分别放入质量分数为3.5%的NaCl溶液和质量分数为5%的醋酸溶液中进行耐蚀性对比实验。结果表明:相对于AZ 91D基体,Ni-Cu-P镀层和Ni-Ce-P镀层在质量分数为5%的醋酸溶液中耐蚀性分别提高了50倍和12.8倍,在质量分数为3.5%的NaCl溶液中分别提高了2.76倍和91.63倍;经封孔和热处理封孔后的耐蚀性均有明显提高。实验表明:在AZ 91D镁合金表面化学沉积Ni-Ce-P镀层的综合耐蚀性能优于化学沉积Ni-Cu-P镀层的。该实验有助于解决镁合金的耐蚀性问题、提高其表面性能和拓宽其应用前景。 相似文献
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采用正交试验研究了稳定剂硫酸铜、碘酸钾、DL-半胱氨酸和硫酸铈复合使用对化学镀Ni-P合金镀液稳定性、镀速、镀层磷含量和孔隙率等性能的影响变化规律。结果表明,各种稳定剂之间有相互促进作用,综合性能明显优于单一稳定剂,且复合使用采用了清洁的原料,替代了重金属Pb2+;稳定剂硫酸铜、碘酸钾、DL-半胱氨酸和硫酸铈最佳复配的质量浓度分别为:25、20、3和7.5mg/L,镀后测得镀速12.54μm/h、镀液稳定常数91.85%、孔隙率0、镀层磷质量分数为10.25%。 相似文献
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镁及镁合金化学镀Ni-Cu-P三元合金工艺 总被引:6,自引:2,他引:6
研究了镁及镁合金的化学镀Ni-Cu-P三元合金工艺,通过正交试验获得了最佳的镀覆条件。并对镀层的组织结构及其性能进行了测试,所得的Ni-Cu-P三元非晶态镀层结合力好,具有良好的导电性和耐蚀性能。 相似文献
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对化学镀Ni-P合金镀层进行铬酸盐钝化处理,并研究了钝化温度和钝化时间对化学镀NiP合金镀层耐蚀性的影响。结果表明:钝化处理可以显著提高化学镀Ni-P合金镀层的耐蚀性。经40g/L重铬酸钾钝化的化学镀Ni-P合金镀层的耐蚀性明显优于经5g/L重铬酸钾钝化的化学镀Ni-P合金镀层的耐蚀性。随着钝化温度的升高或钝化时间的延长,化学镀Ni-P合金镀层的耐蚀性增强。 相似文献
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功能梯度Ni-P合金镀层在酸性和碱性介质中的电化学腐蚀行为 总被引:4,自引:1,他引:3
通过电镀法制备了功能梯度N i-P合金镀层。SEM形貌照片显示,梯度层截面致密、无明显的宏观界面;400℃热处理前后梯度层中P含量分布曲线表明,从界面到镀层表面,P含量逐渐降低,呈现明显的梯度变化。在质量分数分别为10%的盐酸和氢氧化钠介质中的动电位极化曲线和电化学交流阻抗谱分析、含氯酸性介质中的腐蚀前后的表面形貌照片表明,与硬铬镀层相比,经过400℃热处理后的梯度N i-P合金镀层的腐蚀电位提高了600 mV以上,腐蚀电流分别降低了2个和1个数量级,阻抗值亦明显提高,而且,其腐蚀前无裂纹,腐蚀后仅发生轻微的点蚀现象。梯度N i-P合金镀层较硬铬镀层表现出更优异的耐蚀性能。 相似文献
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Nickel-tetraaminophthalocyanine [TAPcNi] was electropolymerized from the complex monomeric solution, onto carbon steel substrates, yielding thin adherent films of poly[TAPcNi]. The investigation of such polymer-modified electrodes was carried out by means of cyclic voltammetry, UV-vis spectroscopy, FT-IR spectroscopy and spectroelectrochemistry. The preparation of TAPcNi modified electrode was also carried out by electropolymerization of a preformed molecular film of TAPcNi, after applying a drop of TAPcNi dimethylsulphoxide solution onto carbon steel, and allowing it to dry. The comparison of the corrosion behavior of the two types of polymer-coated electrodes was carried out by electrochemical impedance spectroscopy (EIS) in acid medium. It was found that the structure and morphology of each polymer greatly influence their redox behavior and corrosion inhibition performance for steel in hydrochloric acid. The film prepared by the drop-dry method offered a better corrosion protective efficiency while the electropolymerized film presented a more conductive behavior. 相似文献
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Fakiha El-Taib Heakal Amany Mohammed Fekry Mohamad Ziad Fatayerji 《Journal of Applied Electrochemistry》2009,39(9):1633-1642
Induced passivation of AZ91D magnesium alloy in phosphate solution was carried out both chemically, using various inorganic
oxidants, namely, molybdate, vanadate and iodate, as well as electrochemically by anodizing the alloy under various controlled
overpotentials within the range 0.1–3.4 V. In acidic phosphate (pH 4.5), molybdate and vanadate anions exhibit similar behavior,
as they show a dissolution effect at lower concentrations and passivation at higher concentrations. On the other hand, iodate
anions shows critical behavior with a passivation effect up to 0.1 mM and depassivation for higher concentrations. Generally,
over the concentration domain (0.01–1.0 mM) the results reveal small inhibitive effects with maximum values of 19.7% for and 24–25% for and manifesting weak propensities for these inorganic species to enhance the corrosion resistance of AZ91D alloy in acidic phosphate
medium. The effect of anodic potential on the characteristics of surface films formed on the alloy in alkaline phosphate solution
(pH 11.9) indicates that higher forming overpotential induces better passivation due to the formation of rather thicker and
more resistive anodic films. The stability of the films is greater in alkaline as compared to acidic phosphate solutions. 相似文献
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铜及铜合金本身没有催化活性,其诱发方法比较复杂。综述了外接电源法、化学活化法、电化学活化法等铜及铜合金化学镀Ni-P合金镀层的诱发方法,并展望了诱发方法的发展方向。 相似文献