铁电极上HEDP镀铜的电化学行为

通过测量开路电位一时间曲线和阴极极化曲线,研究了HEDP镀铜液在金属铁上电沉积铜的电化学行为.结果表明,HEDP镀铜液的组成影响金属铁在溶液中的稳定开路电位和金属铁上电沉积铜的阴极极化.增大溶液中HEDP的浓度或提高HEDP与Cu2+的摩尔比,铁电极的稳定开路电位负移,可减缓和消除铁与铜离子的置换反应,提高铜镀层与铁基体的结合力;金属铁上电沉积铜的阴极极化增大,有利于得到致密的铜镀层.镀液pH升高,铁在镀液中的稳定开路电位稍有正移,但在金属铁上电沉积铜的阴极极化增大,在HEDP镀铜液中电沉积铜的阴极过程发生电化学极化,阴极极化曲线服从Tafel关系.     

不同主盐对羟基亚乙基二膦酸体系镀铜的影响

通过赫尔槽试验和方槽试验,研究了不同主盐对HEDP(羟基亚乙基二膦酸)体系电镀铜沉积速率、电流效率、镀层外观、厚度、结合力等的影响。镀液组成为:HEDP160g/L,Cu2+10g/L,K2CO360g/L,pH9.0。结果表明,由于阴离子不同,铜盐种类会影响电镀过程和镀层性能。HEDP体系镀铜液的最佳主盐为CuSO4·5H2O。以CuSO4·5H2O为主盐时,电流效率为92.5%,镀速为0.18μm/min,所得铜镀层表面平整、致密,与钢铁基体的结合力良好。     

酸性硫酸盐体系镀铜中铜阳极的电化学行为

通过测量阳极极化曲线、循环伏安曲线等电化学方法研究了酸性硫酸盐镀铜溶液中铜阳极的电化学行为,分析了镀液组成和工艺条件对铜阳极溶解和钝化过程的影响。结果表明,纯铜阳极在酸性硫酸盐溶液中发生电化学溶解的电势范围较窄,容易发生钝化,在阳极电势达3.0 V(相对于饱和甘汞电极)后仍无过钝化或析氧现象。完全钝化的铜阳极重新通电后依然能发生正常的电化学溶解。磷铜阳极的电化学溶解性能稍好于纯铜阳极。增大硫酸铜质量浓度和加入添加剂HN-Super-A使铜阳极更易钝化,而增大硫酸质量浓度、加入添加剂HN-Super-Mμ和升温有利于铜阳极的电化学溶解。电镀过程中的电流密度不应超过铜阳极的临界钝化电流密度,否则铜阳极容易钝化。     

HEDP镀铜液在铜电极上的电化学行为

采用测量开路电位-时间曲线和阴极极化曲线的方法,研究了铜电极上HEDP镀铜的电化学行为.结果表明,HEDP体系的溶液组成与温度都会影响铜电极的稳定开路电位,电镀铜过程的阴极极化(镀层结晶质量)与极化度(镀液分散能力).溶液中HEDP浓度升高,则稳定开路电位变负,阴极极化和极化度增大,有利于电沉积铜的电极过程.溶液pH升高时,稳定开路电位变负,电沉积铜的阴极极化增大.溶液温度降低时,电沉积铜的阴极极化增大.阴极极化较小时的极化度较大,且随pH的升高或温度的降低而明显增大.     

问题解答

问:1、请问光亮酸性镀铜液中亚铜的影响与处理方法。2、请问光亮镍1.4丁炔二醇—糖精体系中十二烷基硫酸钠的使用量及注意事项。 (福建省长河县一号信箱郭承宗)答:1.在酸性光亮镀铜溶液中,铜阳极主要是溶解成二价铜离子,在阴极上放电还原成金属铜。但在电镀过程中,当铜阳极和镀液中二价铜接触时,可能产生下列反应:     

氰化镀液中碳酸钠的去除及溶液的回用

一、概述: 氰化镀铜液的主要成份是铜氰络盐和游离氰化钠,次要或份是苛性钠及碳酸钠。适量碳酸钠的存在能使溶液具有缓冲性能,而且有降低阳极极化和增加镀液导电性能的作用,一般来说在配制氰化镀铜液时, 加入适量碳酸钠(20-30克/升)是有利无害的。但是氰化镀铜液在使用过程中,由于长期与空气接触,吸收空气中的二氧化碳及氧气,而使碳酸钠的含量不断增加,其化学反应为: ① 2NaOH+CO_2(空气)→Na_2CO_3+H_2O ② 2NaCN+2H_2O+2NaOH+O_2(空气)→2Na_2CO_3+2NH_3↑当碳酸钠含量过高(超过130克/升)时,会使阳极效率下降,镀层疏松,阳极钝化(不能正常溶解),铜含量不断下降。当镀液中的铜离子降至一定量时,阴极     

钢铁基体上HEDP体系无氰滚镀铜工艺

探讨了HEDP(羟基乙叉二膦酸)溶液体系滚镀铜工艺的可行性。通过正交试验和单因素实验研究了配位剂含量、主盐含量、电流、温度、装载量和施镀时间对滚镀铜的影响,得到最佳配方和工艺条件为:HEDP 120 g/L,Cu SO4·5H2O 16 g/L,K2CO3 60 g/L,p H 9.5,温度50°C,阴极电流2.0 A,滚筒转速15 r/min,装载量50 g/筒。在该条件下滚镀1 h,可获得高、低电流密度区平均厚度分别为7.39μm和1.60μm,与钢铁基体结合良好的半光亮铜镀层。该滚镀铜工艺基本满足预镀铜的要求,但对有光亮度要求的产品,需要往镀液中加入适量添加剂HEAS。     

ABS塑料电镀铜工艺的研究

用乙二醛取代甲醛作为还原剂在ABS塑料上化学预镀铜,然后在碱式碳酸铜为主盐的碱性镀铜液电镀。研究了电镀液组成、pH对镀层结构的影响。最佳镀铜工艺为27g/L KNaC4H4O6、25 g/L CuCO3.Cu(OH)2.H2O、250 g/L C6H8O7、10g/L NaHCO3,pH为8.5,Jκ为1.0A/dm2,t为30min。采用电子扫描电镜观察和X-射线衍射仪分析表征镀层具有单质铜的特征,镀层均匀、致密。结果表明碱性镀液可以有效地保护化学预镀层。     

无氰镀铜的实验研究与生产应用进展(一)

分析了基于硫酸盐光亮酸性镀铜体系的钢铁件浸镀铜工艺工业化应用的不可行性,以及浸镀与电沉积相结合的酸性镀铜工艺的特点.介绍了酸铜光亮剂、钢铁件活化原理、无氰碱铜配位荆等研究的最新进展.指出HEDP无氰碱铜镀液具有化学活化作用,以及预浸能提高镀层结合力.     

第十五讲──电镀用直流电源(一)

分析了基于硫酸盐光亮酸性镀铜体系的钢铁件浸镀铜工艺工业化应用的不可行性,以及浸镀与电沉积相结合的酸性镀铜工艺的特点.介绍了酸铜光亮剂、钢铁件活化原理、无氰碱铜配位荆等研究的最新进展.指出HEDP无氰碱铜镀液具有化学活化作用,以及预浸能提高镀层结合力.     

铜及铜合金着色

简述了铜及铜合金着色的原理.总结了铜及铜合金着黑色、褐色、绿色、蓝色的工艺配方及操作条件,介绍了手工点涂铜绿(铜锈)、双色点蚀(先着黑色再点蚀铜绿)、套色、着土黄铜绿色等多种特殊的着色工艺.     

Electrocatalytic oxidation of ethanol at copper bromide modified copper electrode in comparison to bare and copper chloride modified copper electrodes

Copper bromide modified copper electrode was prepared and used to electrocatalytic oxidation of ethanol. Scanning electron microscopy and energy dispersive x-ray experiments suggested the formation of thin layer of copper bromide on the copper surface. The j₀ for copper bromide modified copper and copper chloride modified copper electrodes are 9.8 and 5.7 folds respectively higher than for that of bare copper electrode. For copper bromide modified copper electrode, the charge transfer coefficient (α) and the number of electrons involved in the rate determining step (n_α) were calculated as 0.44 and 1 respectively.     

两种含铜杀菌剂中铜含量分析方法的研究

利用氧化还原滴定法测定86.2%氧化亚铜可湿性粉剂、铜甲七十二中氧化亚铜的含量,分析了影响氧化亚铜测定的因素。设备简单,方法快速、准确。方法的变异系数分别为0.31%和0.51%,回收率分别为99.5%和99.6%。分析方法精密度好,准确度高。     

新型铜及铜合金光亮酸洗工艺

介绍了一种铜及铜合金无硝酸、无铬光亮酸洗工艺,其主要工序包括化学除油、盐酸漂洗和化学出光。通过正交试验对化学出光溶液组成进行优化,得到最优配方为:H2SO415%,H3PO420%,出光剂A(含氧化剂、缓蚀剂及表面活性剂)20%。该新型抛光剂适用于多种铜及铜合金,工件的光泽与传统混酸洗工艺相当,在自动线上必要的38s内不会对工件产生过腐蚀。     

Oxidation of the copper alloy with pure copper plating

The oxidation failure of a copper alloy lead frame with/without a copper plating layer was investigated. The oxidation rate and adhesion strength of oxide films on copper alloy substrates were studied by measuring the thickness and by carrying out peel tests. The adhesion strength of the oxide film was mainly influenced by the composition but not the thickness of the oxide film. The highest adhesion strength was obtained when the oxide film was composed mainly of Cu₂O. When the thickness of the copper preplated layer was over 0.165?μm, the Cu atoms of the preplated copper were available for oxidation. Thus the oxidation process was within the copper preplated layer, and the main product of the oxidation was Cu₂O. It was found that the large column grain of the oxide film on the copper alloy with a copper plated layer, favored the diffusion of copper or oxygen atoms that led to the formation of Cu₂O, and lead to higher adhesion strength. This indicated that the oxidation resistance of a copper alloy lead frame can be effectively improved by electroplating copper.     

Dissolution from electrodeposited copper–cobalt–copper sandwiches

The electrochemical behaviour of electrodeposited Co–Cu/Cu multilayers from citrate electrolytes was investigated using cyclic voltammetry and stripping techniques at a rotating ring disc electrode. Copper and cobalt–copper alloy sandwiches were deposited from an electrolyte containing 0.0125 M CuSO₄, 0.250 M CoSO₄ and 0.265 M trisodium citrate at two different pHs, 1.7 and 6.0. The Cu/Co–Cu/Cu sandwich is representative of a single layer in a Co–Cu/Cu multilayer deposit, which is known to exhibit unusual physical and magnetic properties. Results from cyclic voltammetry and detection of dissolving species at the ring showed that cobalt is stripped from a Cu/Co–Cu/Cu sandwich even when a copper layer as thick as 600 nm covers the Co–Cu alloy. Scanning electron microscopy showed that cobalt can dissolve from the deposit easily because the copper layer covering the Co–Cu alloy is porous. A separate series of experiments with Cu/Co–Ni–Cu/Cu sandwich showed that cobalt does not dissolve from these deposits because the addition of nickel stabilises cobalt in the Co–Ni–Cu alloy.     

萃取光度法测定微量铜

以三氯甲烷作萃取剂，PAN作显色剂，通过光度法测定镀铜废水中的微量铜，选择了适合的测量波长，讨论了酸度，萃取剂用量及振荡时间对萃取率的影响，分析了干扰元素的影响及消除，该方法准确度高，可测量0．01－1．00μg/mL的微量铜。     

Recovery of copper from copper concentrator tailings by leaching

Tailings from a chalcopyrite beneficiation plant (concentrator) have been leached with dilute ferric chloride in a packed bed. The effect of leaching time and packed bed height on the conversion of cuprous sulphide (present in tailings) has been determined. For predicting the conversion, an expression based on the shrinking core model has been derived and compared with the experimental data. At low conversion, the agreement is good, but at intermediate and high conversion the deviation is considerable.     

A comparison of the rate of copper deposition at mercury,copper amalgam and copper metal

The rate of reduction of Cu²⁺ ions is slower on solid copper than on mercury. The reason probably lies the adsorption of Cu²⁺ ions on mercury.     

Electrodeposition of copper on copper in the presence of dithiothreitol

Studies of the -SH group effect present in dithiothreitol (DTE) with respect to morphology and electrode kinetics of copper electrodeposits on the (1 1 1) plane of a copper single crystal and polycrystalline copper from highly purified solutions of acidified copper sulphate were made. At 2.0 and 5.0 mA cm^–2 there was a truncation of pyramids to layers and ridges and then to polycrystalline growth with an increase in the concentration of DTE in the bath. At higher current densities the change was from pyramids to thin hexagonal blocks, dragged pyramids and then to polycrystalline growth. Interestingly, the above morphological changes repeated at two different concentrations of DTE corresponding to two -SH groups present in the molecule. Levelling of the grains was observed at all current densities studied on a polycrystalline substrate. The electrode kinetic parameters have been correlated with the morphological changes and transport mechanisms have been proposed for different concentrations of the additive.