共查询到20条相似文献,搜索用时 31 毫秒
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化学镀广泛应用于非金属的电镀、电铸前的施加导电层。化学镀沉积层质量与其在零件上的附着力有着密切的关系 ,重视对化学镀沉积层内应力的研究 ,开发一个低温、低内应力的化学镀镍工艺 ,对于化学镀沉积层的推广应用有着十分重要的意义。本文采用正交实验方法对低温、低内应力化学镀镍工艺进行了系统研究 ,开发出了一个低温、低内应力的化学镀镍工艺。在实验过程中发现沉积层内应力同其在零件上的结合力具有密切关系并对其进行了初步探讨。1 实验方法1 1 正交实验根据探索性实验结果分析 ,影响化学镀镍层内应力σ和沉积层速率r的主要因… 相似文献
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以TiO2为载体,N iB为诱导剂,粉末化学镀法制备了负载型纳米N i催化剂.通过TEM、HRTEM、XRD和ICP技术对催化剂物性进行了表征.结果表明,碱性镀液可使载体表面均匀负载微晶结构纳米N i团簇,尺度为35nm左右.该负载型纳米N i在对氯硝基苯选择加氢反应中表现出很高催化加氢活性,并能有效抑制脱氯,达到了工业骨架镍水平.由酸性镀液得到的负载型非晶态纳米N i-P合金具有较弱的催化对氯硝基苯加氢活性.反应温度对反应时间和脱氯率有明显影响. 相似文献
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研究乙二胺稳定剂对化学镀N i-B合金沉积速率和镀液稳定性的影响.实验表明,少量乙二胺可改善镀液的稳定性.镀液的电化学测试发现,乙二胺对体系的阳极过程和阴极过程均有影响,还原剂的氧化电流和合金的还原电流均随乙二胺加入量的增加而减少.红外光谱显示乙二胺附在镍基体表面发生化学吸附,从而抑制了还原剂的氧化,降低N i-B化学沉积速率(稳定了镀液). 相似文献
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通过化学镀技术制备了亚微米级的Ni-P镀层石墨粉复合粉体新材料(即Ni-PC).采用扫描电子显微镜、X-射线能谱仪、X-射线粉末衍射仪对Ni-P-C复合粉体分别进行表面形貌分析、表面成分分析和物相分析.通过对Ni-P-C材料电极进行电解水析氢、循环伏安和Tafel极化等电化学测试,研究对比了Ni-P-C(石墨)材料与试剂石墨粉体以及纯Ni电极的电化学催化产氢性能.结果表明:利用化学镀技术成功地在石墨粉体表面镀上了一层亚微米级且均匀、致密的非晶态Ni-P合金.Ni-P-C(石墨)复合电极材料析氢能力强,具有良好的电化学活性. 相似文献
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Kazarinov I. A. Burashnikova M. M. Stepanov A. N. 《Russian Journal of Applied Chemistry》2001,74(3):430-433
The structural and electrochemical characteristics of cadmium electrodes with nickel introduced in metallic state into the active material of the electrode by electroless plating were studied. The specific role played by heterophase interactions between nickel and cadmium in the mechanism of cadmium electrode activation was substantiated experimentally. 相似文献
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Zhijie Wu Shaohui Ge Minghui Zhang Wei Li Keyi Tao 《Journal of colloid and interface science》2009,330(2):359-366
Nickel nanoparticles supported on metal oxides were prepared by a modified electroless nickel-plating method. The process and mechanism of electroless plating were studied by changing the active metal (Ag) loading, acidity, and surface area of metal oxides and were characterized by UV–vis spectroscopy, transmission electron microscopy, scanning electron microscopy, and H2 chemisorption. The results showed that the dispersion of nickel nanoparticles was dependent on the interface reaction between the metal oxide and the plating solution or the active metal and the plating solution. The Ag loading and acidity of the metal oxide mainly affected the interface reaction to change the dispersion of nickel nanoparticles. The use of ultrasonic waves and microwaves and the change of solvents from water to ethylene glycol in the electroless plating could affect the dispersion and size of nickel nanoparticles. 相似文献
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铝表面前处理及化学沉积镍初期行为 总被引:3,自引:0,他引:3
利用开路电位-时间(EOCP-t)曲线,研究铝表面经浸镍和化学预镀镍前处理后,化学沉积镍的初期行为;通过扫描电子显微镜(SEM)观察铝表面经前处理后的表面形貌.结果表明:未经及经前处理的铝表面,化学沉积镍的初期行为都经历去氧化膜、活化、混合控制以及化学沉积过程.经过浸镍和化学预镀镍前处理后的铝表面附着细小的镍颗粒.依据EOCP-t和SEM的最佳实验结果,在含有络合剂和还原剂的碱性预镀镍溶液中,经二次化学预镀镍前处理,成功实现铝基底弱酸性化学镀镍.所获得的化学镀镍层与铝基底结合牢固,呈团颗粒状形貌和非晶态结构. 相似文献
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《Electrochemistry communications》1999,1(11):513-516
Electroless cobalt plating on spherical nickel hydroxide is tested in order to improve the conductivity of Ni(OH)2 and the capacity of the electrode. The factors affecting the process of electroless cobalt plating are cobalt solution, temperature and pH, etc. The effects have been examined and the optimum process parameters have been obtained. The nickel hydroxide electrode which is made by nickel hydroxide deposited cobalt has excellent performance, the results showing that electroless cobalt plating on the surface of spherical nickel hydroxide particles is an effective method for modifying electrodes. 相似文献
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用重量法测定了卤离子对化学沉积镍速度的影响.并借助电化学方法研究了卤离子对镍的化学沉积过程的极化曲线和稳定电位的影响.探讨了卤离子加速和稳定化学沉积镍的机理 相似文献
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Uniform and stable core-shell microspheres composed of a poly(methyl methacrylate) (PMMA) core and a thin metallic shell of nickel-phosphorus, cobalt-phosphorus, or mixed metal alloys (CoNiP, NiFeP, CoFeP) were prepared by dispersion polymerization of methyl methacrylate followed by electroless plating. The presence of the metallic shell around the particles was confirmed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and photoelectron spectroscopy. Transmission electron microscopy images of the cross-section of individual particles show that the thickness of the metal/alloy can be precisely tuned by adjusting the immersion time of the microspheres in the electroless bath. Depending on the deposited metallic material, various magnetic properties, from paramagnetic to ferromagnetic, are achieved. Finally, uniform hollow metallic spheres composed of nickel, cobalt, or nickel-cobalt alloy are obtained by dissolving the polymer core. 相似文献
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通过极化曲线研究了3种不同溶液(阴极液、阳极液和完整镀液)的电化学行为,测定了主盐、还原剂浓度以及镀液pH和体系温度对化学镀镍沉积速率的影响. 与直接在镁合金上化学镀镍并使用重量分析法得到的沉积速率相比较发现,完整镀液体系的极化曲线才能真实地反映化学镀镍的沉积过程,其过程不能简单视为由彼此完全独立毫无关联的阴阳极半反应构成. 根据Butler-Volmer公式,本化学镀液体系的化学镀镍过程属混合控制,其表观反应活化能为42.89 kJ·mol-1. 相似文献
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V. D. Skopintsev T. D. Firsova E. G. Vinokurov 《Russian Journal of Applied Chemistry》2015,88(12):1976-1980
The possibility of using metal-plated carbon and basalt fabrics for shielding electromagnetic radiation in a wide frequency range was demonstrated. The electrophysical characteristics of carbon, metal-plated carbon, and metal-plated basalt fabrics were compared. The optimum conditions of metal plating of complex textile structures, ensuring high electrophysical properties of the resulting combined materials, were determined, including the optimum conditions for pretreatment of nonconducting fibers and fabrics prior to metal plating and compositions of low-temperature electrolytes for electroless copper and nickel plating, with which uniform distribution of the metals can be obtained on each element of the textile structure. 相似文献
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化学镀镍体系次亚磷酸钠氧化中间产物的ESR研究 总被引:4,自引:0,他引:4
化学镀镍是借助 Na H2 PO2 在具有催化活性金属表面的阳极氧化将溶液中的镍离子还原成金属镍 .伴随镍的沉积 ,表面同时有氢气析出 .同位素研究表明 [1,2 ] ,析出的氢气一部分为溶液中 H+或 H2 O的阴极还原 ,另一部分来自 Na H2 PO2 的阳极氧化过程 .Meerakker等[3~ 5 ] 认为 ,Na H2 PO2 的氧化经历了H2 PO-2 H+ HPO-.2 异相前置转化步骤 ,HPO-.2 阴离子自由基发生阳极氧化的同时伴有 H复合生成氢气过程 .而另一些研究者 [6~ 8] 认为 ,Na H2 PO2 的氧化过程为 H2 PO-2 + H2 O H2 PO-3 + 2 H,仅有 H自由基生成 ,并不产生 H… 相似文献
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天然高分子壳聚糖(CS)与聚乙烯醇(PVA)共混后存在强烈的氢键作用能够促进二者相容,形成互穿网络(IPN)结构的CS/PVA二元共混膜。 通过傅里叶红外(FT-IR)和强力测试对共混膜结构及拉伸强力性能进行了表征。 利用掺杂少量氯化钯的CS与PVA共混液的成膜性能,在涤纶织物表面预制一层具有自催化活性的薄膜,并对经过处理后的涤纶织物进行化学镀镍研究。 采用扫描电子显微镜(SEM)、热重分析(TG)、电磁屏蔽效能测试和水洗牢度测试,分别对织物表面形貌、热稳定性、电磁屏蔽性能和结合牢度进行测试。 结果表明,CS与PVA共混液处理后的涤纶织物,经化学镀镍能获得表面均匀致密、导电性优良、与织物结合力良好的镀层。 相似文献