新型可焊性锡铈铋镀层电镀工艺

介绍了新型可焊性锡铈铋镀层电镀工艺的镀液配方和电镀操作条件;测试了镀液的分散能力、阴极电流效率和沉积速率.用铜丝或铜片作镀件,在小槽内电镀,获得的镀层,外观致密均匀,似镜面光亮,结合力强.     

甲基磺酸盐镀液体系可焊性合金镀层的工艺

研究了一种新型可焊性镀层-含银量3%的锡银合金的电镀工艺,选择甲基磺酸亚锡和甲基磺酸银为主盐,柠檬酸钠、碘化钾和三乙醇胺为络合剂,研制了镀覆含银量为3%的最佳镀液配方和施镀工艺条件.通过对镀层可焊性、抗高温氧化性能和表面接触电阻等性能的考察发现,低含银量的锡银合金镀层性能优于锡铅合金镀层,且镀液成分简单、性能稳定、无毒无害,具有广泛的应用前景.     

可焊性光亮锡铋合金电镀工艺研究

研究一种可焊性光亮锡铋合金电镀工艺的镀液配方和电镀操作条件;测试了镀液的分散能力、深镀能力、阴极电流效率和沉积速度;经小槽电镀,获得外观致密均匀、似镜面光亮、结合力强、具有优良的可焊性镀层。     

光亮硫酸盐电镀Zn-Fe合金工艺研究

采用霍尔槽试验对硫酸盐镀锌铁合金光亮剂、辅助光亮剂、载体光亮剂进行了筛选,研究成功了一种酸性硫酸盐体系电镀低铁含量的光亮zn-Fe合金镀层工艺,探讨了主盐、络合剂、导电盐、稳定剂、工艺条件的影响,检测了镀液、镀层性能.结果表明:该镀液成分方便,镀液稳定,操作简单,所得镀层结晶细致、光亮平整,其耐蚀性与光亮度明显优于镀锌层,黑色钝化后黝黑发亮.     

氯化物电镀Zn—P合金的研究

研究了Ｚｎ－Ｐ合金电镀液组成及工艺条件对镀层含磷量的影响，在最佳工艺参数条件下，可得到磷的质量分数为０．１％左右的Ｚｎ－Ｐ合金镀层。对镀液、镀层性能进行了测试，实验证明经银白色钝化后的Ｚｎ－Ｐ合金镀层的耐蚀性能是纯锌镀层的２倍以上。     

Fe-Ni新型UBM薄膜的晶圆电镀工艺研究

利用改良型硫酸盐-氯化物镀液体系,进行了晶圆级Fe-Ni凸点下金属层（UBM）电镀工艺的开发研究.研究了镀液中Fe²⁺含量、电镀温度及电流密度对镀层成分的影响规律,得到了特定工艺条件下镀层成分控制的完整曲线;测量了不同电镀时间和不同电流密度下的镀层生长速率,为实际生产中控制UBM镀层的厚度提供了依据;利用XRD和TEM对镀层的晶体结构及微观形貌进行了表征;利用滴定、等离子体发射光谱（ICP）等手段,对镀液在生产及静置条件下主盐离子浓度的变化趋势进行了监测,测定了抗坏血酸在镀液体系中与Fe³⁺的反应能力,提出了镀液的日常维护、保存、调控方案以及:Fe³⁺的抑制方案.     

锌镍合金电镀技术的研究

研究了采用锌镍合金为阳极进行电镀时,工艺条件对锌镍合金镀层镍含量的影响,寻找出耐蚀性是镀锌层５倍以上Ｚｎ－Ｎｉ（１３％）合金镀层电镀的工艺条件。对镀液进行了连续电镀试验,电镀后镀液中金属离子浓度波动小,采用合金阳极进行电镀可以基本维持金属离子浓度的稳定,还应用多种测试方法,检测了镀层的结合力。     

MLCC三层镀中甲基磺酸镀锡体系工艺条件对锡镀层性能影响的研究

研究了片式多层陶瓷电容器(MLCC)三层镀中甲基磺酸镀纯锡体系pH值、温度、电流密度等工艺条件及杂质金属离子对镀液稳定性、镀层结构和性能等方面的影响。从电流效率、沉积速度及锡镀层表面的扫描电镜等方面,对比了不同pH值、温度、电流密度以及锡镀液中掺杂Cu2+、Ni2+后对锡镀层结构和性能的影响。研究结果给出了电镀工艺中最佳的pH值为3.5±0.2、温度为(23±2)℃、电流密度可以有较宽的范围,当镀液中掺有镍、铜等杂离子会对镀层产生负面影响,在给出的工艺参数下电镀,可以确保镀出最佳的纯锡镀层。     

正交试验优化电镀Zn-Ni-P合金工艺

选取影响电镀Zn-Ni-P合金的6个工艺参数，设计了125(56)正交试验方案，探讨了镀液组成和电镀制度对Zn-Ni—P合金镀层性能的影响，用极差法分析了各工艺参数对镀层性能影响的显著性并确定了最佳工艺条件。优化验证实验结果表明：该工艺稳定，得到光亮、致密、外观平整的Zn-Ni—P合金镀层，得到的锌镍磷合金镀层的耐蚀性优于锌镍合金，且其耐蚀性随镀层中磷含量的增大而提高。     

改善橡胶减震器金属件和橡胶粘合性能的措施

橡胶金属件电镀铜锌合金对提高其粘合性能具有重要作用。文中探讨了镀液中的各种成份和工艺条件对镀层内铜锌含量的增减和粘合性能的影响,确定了镀液的最佳工艺条件。     

无氰电镀液中超声电沉积耐腐蚀纳米晶铜镀层

通过超声辅助电沉积法,在无氰络合电镀液中以高阴极电流密度在钕铁硼磁体上电沉积获得纳米晶铜防护镀层,研究了不同超声波频率下的镀层形貌、晶粒尺寸、显微硬度和耐腐蚀性能。结果表明,随着超声波频率的增加,络合电镀液体系的铜电沉积有效阴极电流密度显著增加,相应的阴极电流效率也提高,从而获得致密的纳米晶铜镀层。在阴极电流密度为4.0 A·dm^-2和超声波频率为40 kHz的条件下,能够获得平均晶粒尺寸为18.8 nm的铜镀层。超声辅助电沉积法还能促进烧结钕铁硼基体盲孔内的铜沉积,从而改善基体与镀层之间的结合力。在同样的镀层厚度下,烧结钕铁硼表面所沉积镀层的耐腐蚀性随超声波频率的提高而优化。     

[Bmim]OTf-ZnCl2-PC体系超声电镀锌工艺及镀层耐蚀性能研究

目的研究超声功率对镀层表面形貌和镀层耐蚀性的影响。方法采用[Bmim]OTf-Zn Cl2-PC离子液体,利用超声电沉积方法,在铜电极表面沉积金属锌。利用电化学工作站考察阴极极化曲线以及镀层的耐蚀性能,测定镀层的电沉积速度。利用扫描电镜分析镀层的表面形貌,显微维氏硬度计测定镀层的硬度,考查超声波功率对镀层性能的影响。结果加入超声波后,金属的还原电位发生正移,镀层的沉积速度从无超声波作用时的4.652 g/(m~2·min)下降到2.146 g/(m~2·min),镀层表面均匀、致密,结合力强,表面硬度从无超声波作用时的185HV增加至251HV。根据Tafel直线外推法得出镀层的腐蚀电位从-1.14 V增加到-0.62 V,腐蚀电流密度从8.8μA/cm~2降低到2.3μA/cm~2,镀层的耐蚀性能变好。结论增加超声波功率明显提高镀层的表面质量,粗糙度逐渐变好,镀层耐蚀性有明显增加的趋势。综合考虑超声电沉积锌镀层的最佳超声功率为120 k W·h。     

Pretreatment-free Ni−P plating on magnesium alloy at low temperatures

Electrochemically promoted electroless plating (EPEP) was used for the application of pretreatment-free Ni?P coating on AM60B magnesium alloy at low temperatures and the obtained coating was characterized by SEM, AFM, EDS and XRD techniques. Compact, uniform, and medium-phosphorus Ni?P coating with mixed crystalline?amorphous microstructure was obtained by applying a cathodic current density of 4 mA/cm² at 50 °C. Also, island-like nickel clusters were deposited on the alloy surface under the same plating condition but without applying the cathodic current. In addition, the durability of the magnesium alloy against corrosion was strongly improved after plating via EPEP technique which was revealed by electrochemical examinations in 3.5% NaCl (mass fraction) corrosive electrolyte. The results of the electrochemical examinations were confirmed by microscopic observations. Thickness, microhardness, porosity and adhesive strength of the deposits were also qualified.     

Characterization of Zinc-Cobalt Electrodeposits

The structure and morphology of electrodeposits depend on many factors including temperature, current density, time of deposition and composition of the bath. The properties of an electrodeposit depend on its micro structure. For example corrosion and wear resistance, hardness, internal stress, strength, brightness, electrical conductivity, magnetic properties and leveling are all affected by structure.

The relationships between electroplating parameters such as current density, temperature, bath agitation and electrolyte composition have been investigated for the zinc-cobalt system. It was found that electrolyte composition and temperature affect both deposit composition and morphology. The cathodic current efficiency decreased with current density and hardness was raised with increasing cobalt content in the deposit.

Three powerful techniques were used to access the microstructure of zinc-cobalt deposits: scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The results show that the alloy is constituted of a single phase of a solid solution of cobalt dissolved in zinc within an hexagonal crystal system. The deposit is porous and changes from dendritic to nodular with increasing cobalt content.     

Properties of ‘Sulpho-Chromispel-I’ electrolyte of standard concentration for the electrodeposition of chromium

The most important properties of non-standard highly efficient “Sulpho-Chromispel- I” type electrolytes for chromium plating have been investigated. They contain as side anions catalysing the cathodic process, both SO^2-₄ and I^?. The effects of cathodic current density and concentration of hydroiodic acid on the total current distribution are evaluated. The deposition rate is determined. The effect of operating parameters on the throwing power is established. The properties of the electrolytes studied are compared with those of standard sulphate electrolytes and “Chromispel-I” compositions. The most efficient electrolyte comprises CrO₃:I- = 20:1 and 20 cm³ dm^?3 sulphuric acid. The deposition rate can reach a value of 250 μm h^?1 at a current density of 200 A dm^?2. The throwing power of this electrolyte is close to that of standard sulphate electrolytes. As a whole “Sulpho-Chromispel-I” electrolytes exhibit lower throwing power compared to standard sulphate electrolytes or pure “Chromispel-I” electrolytes. They are recommended for chromium plating details of simple profile.     

Electrolytic deposition of Ni-Co-SiC nano-coating for erosion-enhanced corrosion of carbon steel pipes in oilsand slurry

Erosion-enhanced corrosion constitutes an essential threat to the integrity of the oilsand slurry hydrotransport system. In this work, a Ni-Co-SiC nano-coating technology was developed by electrolytic deposition on the carbon steel surface to address this problem. Results demonstrate that the coating develops a compact structure, improving significantly the mechanical properties, including hardness and wear resistance, and the resistance to erosion-enhanced corrosion. The incorporation of SiC nano-particles in the coating, rather than the coating thickness, plays an essential role in the improvement of the coating properties and performance. Furthermore, the electrodepositing parameters, including concentration of SiC in the bath electrolyte, cathodic current density, current pattern and temperature, affect remarkably the content of SiC particles in the coating, and thus the coating performance. An optimal condition was proposed to fabricate the nano-coating for this purpose.     

阴极电流密度对6061铝合金在含Na2WO4电解液中微弧氧化膜结构和耐磨性能的影响

目的 研究恒流模式下阴极电流密度对6061铝合金在含Na2WO4的电解液中制备的微弧氧化膜厚度、形貌、相组成及耐磨性能的影响。方法 固定阳极电流密度为5.0 A/dm²,阴极电流密度分别为0、1.25、2.5、3.75、5.0 A/dm²,对6061铝合金进行微弧氧化40 min。用涡流测厚仪测量了氧化膜的厚度,用扫描电镜观察了微弧氧化膜的表面形貌和截面形貌,用能谱分析仪分析了氧化膜的表面成分,用X射线衍射分析仪分析了微弧氧化膜的相组成,用往复式摩擦磨损试验机测试了氧化膜的耐磨性能。结果 随着阴极电流密度的增加,氧化膜内的W含量逐渐减少,氧化膜颜色逐渐变浅,氧化膜厚度逐渐增加。微弧氧化膜的主要组成相为α-Al2O3和γ-Al2O3。当阴极电流密度从0 A/dm²增加到3.75 A/dm²时,氧化膜内孔洞的数量和尺寸逐渐减少,孔洞到氧化膜/基体界面的距离逐渐增加,氧化膜的耐磨性能逐渐提升。当阴极电流密度为3.75 A/dm²时,氧化膜的磨损率最低,仅为1.07×10^‒4 mm³/(N.m)。但阴极电流密度增加到5.0 A/dm²时,氧化膜表层出现孔洞和剥落,耐磨性能下降。结论 阴极电流的加入有助于增加6061铝合金微弧氧化膜的厚度,提高氧化膜的致密性和耐磨性能,但过高的阴极电流会导致氧化膜表层出现孔洞,降低耐磨性能。     

Electroplating of catalytically active nickel coatings from baths of various anionic compositions

The effect of the nature of bath anions (Cl⁻, SO₄²⁻ and CH₃COO⁻) on the characteristics of the electrochemical plating of nickel coatings, namely, parameters of the cathodic polarization curves, bath stability, and current efficiency, as well as the composition and morphology of deposits and their catalytic activity in the anodic oxidation of hypophosphite ions and cathodic evolution of hydrogen, is studied. The anionic composition of the baths is found to substantially affect not only the kinetics of the deposit growth, but also the properties of the deposit. The differences observed are determined by the complex-forming and buffering properties of the anions.     

Zn/纳米CeO2复合镀层的制备及电化学性能研究

纳米粒子具有一系列特殊的性能,采用电镀的方法在镀层中添加纳米颗粒可改善镀层的某些性能.利用纳米稀土氧化物在基体相中的补强作用以及可能赋予镀层某些新性能的特点,采用复合电镀的方法制备了Zn/纳米CeO2复合镀层,分析了镀液中CeO2颗粒悬浮量、阴极电流密度和镀液温度等因素对复合镀层中纳米CeO2复合量和膜层质量的影响,用正交试验法优选了各工艺参数.采用电化学方法研究了Zn/纳米CeO2复合镀层的耐蚀性.结果表明:复合镀层晶粒细小,平整光滑,显微组织均匀、致密,且镀层耐蚀性能比相同电镀条件下制得的纯锌镀层有所提高.     

The electrodeposition of nanocrystalline Cobalt–Nickel–Phosphorus alloy coatings: a review

The importance of Co–Ni–P alloy deposits is summarised and recent developments are highlighted. Electroplating and electroless deposition of nanocrystalline Co–Ni–P ternary coatings are considered. Nanostructure, physical and mechanical properties (including corrosion resistance) of various bath types and compositions (including pH and electrolyte additives) as well as plating conditions (including current density, temperature and agitation) are summarised. Applications range from wear and corrosion resistant coatings, particularly as a hard chromium replacement to speciality hydrogen evolution electrodes in water electrolysis. Following this concise review, future research needs are briefly listed.