化学镀镍规律及机理探讨

基于化学反应所遵循的物质守恒原理,在已知主要反应物、生成物条件下,利用化学方程式配平法,探讨了不同条件下化学镀镍的基本规律,首次提出了与目前经典化学镀镍理论不同的反应方程式;在此基础上找出了次磷酸利用率规律;利用P-H键断裂理论分析探讨了化学镀镍溶液成分及工艺条件,如稳定剂、pH、装载量、加速剂及络合剂等对化学镀镍的影...     

滚挂结合的双色镀工艺

介绍了在同一金属零件(如纽扣)上局部镀红古铜、局部镀浅黑镍的双色电镀方法.其工艺流程主要包括:电镀酸铜底色,上油墨,二次电镀亮镍,退油墨,三次电镀枪色,捞色(即在滚筒中用涮色粉、茶籽粉等磨料磨去表面镀层),上保护膜.指出了操作过程中的注意事项.该新型双色电镀方法将挂镀与滚镀有效结合,做到了滚镀镀种的双色效果.     

Synthesis of monodisperse nickel‐coated polymer particles by electroless plating method utilizing functional polymeric ligands

In the electroless plating process, to omit a sensitizing process with SnCl₂, we utilized amino‐functional groups on polymer particles. At first, highly monodisperse functional polymer particles could be prepared by a two‐step seeded polymerization of styrene, divinylbenzene, and glycidyl methacrylate. Then, surface epoxy‐functional groups were converted to amino‐functional groups by treating the particles with a diamine. By using these surface amino functionalities, we tried to prepare uniformly metal‐coated monodisperse polymer particles by electroless plating method. The constituents of an electroless nickel solution bath are nickel salt, a reducing agent, suitable complexing agents, and stabilizers. And the metal thickness was simply controlled by changing the loading amount of substrate polymer particles. Morphological observation of nickel‐plated polymer particles was conducted by using optical microscopy, scanning electron microscopy, and transmission electron microscopy. The structural composition of plated nickel was also investigated. Most of all, the function and the efficiency of the amino‐functional group of polymer particles as a polymeric ligand for metal binding was elucidated. From all observations, it was evident that in the electroless metal plating process without any sensitization step, the deposition of metal clusters on substrate particles is largely dependent upon the particle surface functionality. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3801–3808, 2006     

Ni/α-Al2O3纳米复合电镀工艺的研究第四部分──纳米复合镀液及复合镀层的性能

复合镀液的性能与Watts镀液相比,电流效率略低,但分散能力、覆盖能力、整平能力略好,电化学极化明显增强;采用双脉冲电源时镀液的性能比采用直流电源有所改善。复合镀层的各项性能,尤其是硬度、孔隙率、耐磨和耐蚀性能均大大优于Watts镀层;应用脉冲电源除镀层的结晶取向和摩擦因数体现出一定的优越性之外,其他性能并无大的改善。     

钢铁中温光亮化学镀镍新工艺

研究了一种镜面光亮化学镀镍新工艺,优选了镀液配方及工艺条件.该工艺采用有机酸多络合体系,中温酸性化学光亮镀镍.试验表明,该镀层耐蚀性好、结合力强、硬度大、光洁度高,镀层镜面光亮,且光亮剂A无毒,减少了环境污染.     

镁合金化学镀镍层的生长过程

The initial nickel deposition for the direct electroless nickel plating on non-catalytically active magnesium alloy is critical. The surface morphology and composition of the initial nickel plating coating are obtained by means of the scanning electron microscopy (SEM) and the energy dispersive X-ray (EDS). In addition, the mass gain/loss in the initial nickel deposition process was measured by using the electrobalance. The results showed that the MgO coating was gradually corroded by the plating solution, at the same time, MgF2 produced by F , H and MgO was deposited on the substrate during the initial electroless plating process. The nickel of the initial electroless plating was mostly growing on the boundary between the MgF2 coating and the MgO coating of the activation substrate, and then came to two sides. After that, the Ni-P coating growth rate to cover with the MgF2 coating was prior to the MgO coating. The electroless plating was in company with the substrate corrosion, but the electroless plating rate catalyzed by the exchanged nickel was more than the substrate corrosion rate.     

玻璃纤维/环氧树脂复合材料表面金属化工艺研究

提出一种在玻璃纤维/环氧树脂复合材料表面化学镀镍的简化工艺,首先在复合材料表面引入含有镀镍短纤维的过渡层,复合材料与过渡层共固化成型。通过机械粗化、酸化、化学镀工艺成功地在玻璃纤维/环氧树脂复合材料表面沉积一层连续致密的Ni-P镀层。采用超景深显微镜观察化学镀后镀层的表面形貌,并采用SEM对镀层截面特征进行观测。系统地研究了化学镀时间、装载量对镀层表面形貌、镀层厚度与镀层沉积速度的影响规律,并测量了复合材料/镍镀层界面结合强度。试验结果表明,当化学镀时间为8 h、装载量为1.25 dm2/L时,镀层厚度能达到38.96μm,镀层结合强度达到8.45 MPa。     

论连续化泡沫镍的双层化学镀

连续化泡沫镍双层化学镀，是在利用单层聚氨酯海绵作为基体进行化学镀的基础上进行的，能降低化学镀生产成本的方法。通过对实际泡沫镍生产条件的模拟，提出对化学镀镀槽进行简单的设备改进方法，以实现同槽双层镀的过程。     

石膏表面电刷镀镍工艺

介绍了石膏表面电刷镀镍的工艺.石膏样品用环氧树脂封闭处理后,涂刷铜导电胶使其表面金属化,在10~14 V电刷镀镍,随后用高整平镍刷镀液在12~16 V第二次电刷镀镍,可以得到结晶细致的光亮镍镀层,测试了所得镀层的附着力、硬度及厚度.     

PC/ABS合金塑料电镀工艺改进

对卫浴产品用PC/ABS塑料件的电镀工艺进行了改进:以酰胺类膨胀剂替代苯酚类膨胀剂进行预粗化,以改善镀层的完整性和外观;在催化前采用氨基甲酸盐类高分子有机物进行表面调整,以减少氯化钯催化剂的用量,提高表面沉钯的质量,缩短电镀时间。改进后的流程主要包括:预粗化,除油,亲水,粗化,回收,中和,表调,预浸,催化,加速,化学沉镍,活化,预镀铜,镀酸铜,镀半光镍,镀光镍,镀铬,烘干,包装。以改进后的工艺对德国拜耳Bayblend ABS+PC2953和台湾奇美Wonderloy PC/ABS PC-365塑料件进行批量电镀,镀层百格结合力测试全部合格,外观合格率达90%,每小时产值提高了约1200元。     

钢铁件上薄层亮镍的孔隙及其封闭试验

阐述了亮镍镀层孔隙率的危害及影响因素(包括镀层厚度,基体缺陷和粗糙度,待镀表面的洁净度,以及镀液的维护).介绍了降低亮镍镀层孔隙率的主要措施.针对钢铁件上镀薄层亮镍高孔隙率的问题,测试了几种水基缓蚀剂及水溶性清漆的封闭效果,但结果令人失望.采用水溶性蜡封闭剂的效果则较好.     

镁合金化学镀镍工艺的研究

研究了镁合金硫酸镍化学镀镍工艺,得到了最佳的酸洗、活化及镀镍液配方.通过研究发现,镁合金在化学镀镍液中不会受到腐蚀,并初步探讨了化学镀镍的沉积机理.     

新型配位剂对化学镀铜工艺的影响

在以柠檬酸钠为配位剂、次磷酸钠为还原剂的化学镀铜工艺的基础上,加入一种新型配位剂,研究了新的化学镀铜工艺。比较了新化学镀铜工艺与传统的化学镀铜、化学镀镍工艺的不同。结果表明:新型化学镀铜工艺沉积速率快、镀液稳定性好、成本低,是很好的代镍工艺。     

表面化学镀镍处理LiAl0．05Ni0．25Co0．70O2改性研究正极材料的改性研究

采用化学镀的方法在层状LiAl0．05Ni0．25Co0．70O2表面沉积一层镍,通过X-射线衍射、扫描电子显微镜及电化学测试研究其表面形貌、结构和电化学性质。结果表明,所制备的材料表面镀镍层均匀致密,有效地抑制了材料表面与电解液的相互作用。首次放电比容量达到121．51mA·h／g,经过30次循环后容量保持率为91．35％,其循环稳定性能得到明显提高。     

稳定剂对化学镀镍液稳定性的影响

以镀液稳定性、沉积效率、镀层性能为评价指标,研究重金属稳定剂、稀土稳定剂、有机酸稳定剂等不同稳定剂对低温碱性化学镀镍的影响。结果表明:向化学镀镍液中添加以丁二酸、OH-、硫脲为组合的有机酸稳定剂,可以有效提升化学镀镍液的稳定性及沉积效率。     

Effect of surface roughness and mass transfer enhancement on the performance characteristics of nickel-hypophosphite electroless plating baths for metal–ceramic composite membrane fabrication

Mass transfer enhanced electroless plating is a relatively new concept in the field of metal–ceramic composite membrane fabrication. In this article, we present the effect of substrate surface roughness along with various mass transfer enhancement techniques such as solution stirring, membrane stirring and sonication on metal conversion, plating efficiency, thickness, and percent pore densification using electroless plating of nickel on a porous disk shaped ceramic support with a nominal pore size of 700 nm. The plating characteristics were investigated for three different roughness values, stirrer speeds (0–300 rpm) and a loading ratio (defined as membrane area per unit volume of plating solution) value of 196 cm²/L. It was evaluated that stirring as well as sonication had a profound effect on sodium hypophosphite based electroless nickel baths. This led to a reduction in average membrane pore size by 100 nm for stirring and 130 nm for sonication when compared to the base case. Surface roughness was observed to influence the metal deposition characteristics for base case without mass transfer enhancement. Sonication, irrespective of surface roughness, provided the maximum values of selective conversion, densification and membrane thickness along with acceptable values of plating efficiency.     

Preparation of nickel coating on ZTA particles by electroless plating

With the aim to effectively improve the interface between ZrO₂ toughened Al₂O₃ (ZTA) particles and metal matrix, nickel was deposited on the surface of ZTA particles by electroless plating method. Formation mechanism of nickel coating and effects of the solution pH, loading capacity of ZTA particles and temperature on the nickel deposition were investigated. Microstructures, thickness and element distributions of nickel coating were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The results showed that the nickel was successfully deposited on the surface of ZTA particles by electroless plating without noticeable defects. The process of electroless nickel plating could be explained by combination of atomic hydrogen and electrochemistry theories. The interfacial nucleation of nickel is easier to form than spontaneous nucleation in the solution. Deposited Nickel has priority on the surface of ZTA particles comparing to that in solution. The optimal conditions to coat nickel on the surface of ZTA particles are: solution pH 4.7–4.8, loading capacity 15–20?g/L, and electroless plating temperature 85?°C. The ZTA particle reinforced iron matrix composites prepared by powder metallurgy could have better interfacial bonding between ZTA particle and iron matrix because of the nickel coating on the surface of ZTA particle. Nickel diffuses into the iron matrix during the sintering preparation of composite materials. The interface between ZTA particle and iron matrix presents the evidence of non-chemical bonding.     

Electroless plating of moisture‐curable polyurethane undercoating films

The compatibility of using moisture‐curable polyurethane (MCPU) system as a thin undercoating layer with electroless plating process was evaluated. The characteristics of the MCPU before and after chemical etching treatment were analyzed using atomic force microscope (AFM), scanning electrode microscope (SEM), contact‐angle measurements, and (Fourier‐Transform Infrared) FTIR spectroscopy. We found that surface morphology and roughness of the MCPU is affected by curing period and etching times. A proper combination of curing period and etching times are critical for obtaining a fully metallized surface. All MCPU samples that were etched for 15 min show poor plating performance due to surface damage caused by mild etching treatment. A standard pull‐off testing method (ASTM 4541) was used to evaluate the adhesion strength of nickel–MCPU. Only samples that were postcured for 4 days show influence of surface roughness on adhesion strength. On average, samples that were postcured for 7 days before electroless plating showed better adhesion of nickel–MCPU compared with samples that were postcured for 2 or 4 days. The results show that MCPU system can be used as a thin undercoating layer for electroless plating. It also offers smooth metal–polymer interface and therefore has the potential to be exploited for use in many electroless plating applications including in the decorative such as ornaments and display items and also in electronic industries. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1554–1565, 2007     

分步电解法回收化学镀镍废液的研究

采用分步电解法去除化学镀镍废液中的重金属离子及配位剂,并确定了最佳的工艺参数。结果表明:通过对pH值和电解工艺的控制,采用分步电解法能有效回收化学镀镍废液中90%~95%的镍,废液中总配合物的去除率达到98.5%,亚磷酸盐的去除率达到98.0%。电解后的废液可以直接回用于新化学镀镍液的配制。     

化学镀镍液中硫酸镍与次磷酸钠的快速测定

采用光度分析方法研究化学镀镍过程中硫酸镍及次磷酸钠质量浓度的快速测定，建立了标准硫酸镍及标准次磷酸钠质量浓度与吸光度回归方程。对比试验表明，镀液测定的标准偏差小于4％，与化学分析标准法相比，其偏差可控制在6％左右。本法适用于快速检测镀液中主成分含量的变化。