-范文最新推荐- 酸性电解液中锌镍合金电沉积研究 摘要:本论文通过选择合适的阳极及阳极电流控制方式，采用新的添加剂和络合剂实现了锌镍合金电镀。重点研究了酸性镀液中总离子浓度、阴极电流密度、镀液PH值、添加剂、镀液温度、镀液中镍锌含量比对锌镍合金镀层中含镍量的影响规律。采用x射线衍射仪、扫描电镜和多功能电子能谱仪等分析手段，对锌镍合金镀层的成分变化规律、微观形貌和结构、腐蚀产物、钝化膜的结构及成分进行了分析和研究。结果表明：(1)通过此新型的镀液配方和工艺条件，可获得含镍量为912，具有良好外观和耐蚀性的锌镍合金；(2)随镀层厚度的增加，锌的含量增加，镍的含量是先增加后减小，镀层中形成了镍的富积层；(3)含镍量不同，镀层的结构不同。当镀层中镍含量低于6以下时，镍与锌形成固溶体组织η相；当镍含量为610时，还会有弥散的γ相合金存在；当镍含量为1014时，镍与锌形成金属间隙化合物,其会相组织主要为γ相(Ni6Zn21)，当镀层中镍含量高于25时，镀层组织主要是α相，还会有弥散的ζ相(NiZn3)合金；(4)含镍14以下的锌镍合金，其自腐蚀电位随镍含量的增加而增加；(5)锌镍合金镀层腐蚀产物主要是ZnO和ZnCl2•4Zn(OH)2，含有少量的2ZnCO3•3Zn(OH)2，腐蚀产物中没有镍的存在；(6)锌镍合金钝化膜表层主要由CrO3、Na2CrO4和H2O等组成；随钝化温度的升高，钝化膜的厚度增加；在锌镍合金钝化膜与镀层之间形成了富镍层。6714关键词：锌镍合金电镀合金电沉积耐蚀性合金钝化The Research of Zinc - Nickel Alloy Electroplating in AcidicElectrolyteABSTRACT：In this paper, electroplating Zinc-Nickel alloys has been realized by selecting appropriate anode and mode of controlling anode current and adopting new additive and complexantThe new process conditions and solutions of electroplating Zinc-Nickel alloys have been obtained and researched from all aspectsFocus on the influence of nickel content in Zinc-Nickel alloy in the total ion concentration, additives, cathodic current density,PH , plating solution, temperature and the ratio of nickel and Zinc content in the plating solution in the acidic solution .The passivation of Zinc-Nickel alloys has been made from adopting Dew passivation solutions and good process，The metabolic rule of Zinc-Nickel alloy coatings components, microcosmic appearance and structure、corrosion production and the structure of passivation film and components have been analyzed and researched by means of adopting XRD, Glow Discharge Optical Emission Spectrometry，SEM and Multifuetional Electronic Energy Spectrum. The results show：(1)By the new process conditions and solutions of electroplating，the Zinc-Nickel alloys which the content of nickel is in 9 at to 12 at, has good appearance and high corrosion resistance has been obtained(2)When the thickness of Zinc-Nickel alloys coatings increase，the content of zinc increase，but the content of nickel increase at the first some times and then decreaseThere is an enrichment of nickel in the coatings(3)Zinc-Nickel alloys electrodeposits exhibit different alloy phases as a function of their alloy compositionWhen the content of nickel is under 6 at，alloys have η-phrase which is a solid solution of nickel in zincWhen the content of Nickel is 6 at9 at，there is dispersion γ-phraseAlloys ofl014 nickel are γ-phrase mainlyWhen the content of nickel exceeds 25 at，ally have α-phrase mainly and have little ξ-phrase(4) The stabilized potential of alloys that the content of Nickel is under 14increase when the content of Nickel increased. The properties of corrosion resistance of passivation Zinc-Nickel alloys are much more than the properties of passivation Zinc coatings，passivation Cadmium comings and alloys of Cadmium-Titanium(5)The corrosion productions are mainly ZnO and ZnCl2•4Zn(OH)2，have little 2ZnCO3•3Zn(OH)2 and isn't nickel(6) The passivation films of Zinc-Nickel alloy ale mainly made up of CrO3、Na2CrO4 and H2O and there is a enrichment of nickel between the passivation films and alloy coatings. When the passivation temperature increase，the thickness of passivation films increase 酸性电解液中锌镍合金电沉积研究: Key Words：Zinc-Nickel alloyselectroplating alloyeloctrodeposition corrosion resistancealloy passivation目 录1 引言•11.1 本课题研究的目的和和意义•11.2 Zn-Ni合金电镀的研究近展11.2.1 Zn-Ni合金国外研究情况•11.2.2 Zn-Ni合金国内研究情况•21.2.3 Zn-Ni合金的钝化21.2.4 Zn-Ni合金镀层耐蚀性•41.2.5 Zn-Ni合金其他方面的研究及其进展•51.3 合金电镀的应用及分类52 合金电沉积•72.1 合金电沉积的条件•72.2 合金电沉积的类型82.2.1正常共沉积82.2.2非正常共沉积92.3 Zn—Ni合金的电沉积机理102.4 影响合金电沉积的因素•102.4.1 镀液中金属浓度比的影响•102.4.2 镀液中金属总浓度的影响•112.4.3 添加剂的影响112.4.4 电流密度的影响122.4.5 温度的影响122.4.6 镀液PH的影响•122.5 本文研究的背景及主要工作122.5.1研究背景122.5.2主要工作•133 实验部分•143.1 实验药品143.2 实验仪器143.3 试验工艺流程143.4实验工艺参数的影响与讨论143.4.1 镀液中镍锌含量比对酸性液电镀Zn—Ni合金的影响143.4.1.1镍锌含量比对镀层镍含量的影响143.4.1.2镍锌含量比对镀层表面形貌的影响153.4.2总离子浓度对酸性液电镀Z n—N i合金质量的影响•153.4.2.1镀液总离子浓度对镀层中镍含量的影响•163.4.2.2镀液总离子浓度对镀层表面形貌的影响•16 现代工业和科学技术的发展对材料表面的性能提出了越来越高的质量要求。近年来，为了改善镀锌钢铁制品的耐蚀性，由电镀纯锌向电镀锌基合金方向发展4-6。锌基合金镀层主要是Zn—Ni、Zn—Co和Zn—Fe，其中以Zn—Ni合金镀层的耐蚀性为最好。在Zn—Ni合金镀层中，镍含量对镀层耐蚀性的影响很大。有研究表明7-8，含镍量在1015(质量分数)的Zn—Ni合金镀层其耐蚀性最佳，为纯锌镀层的57倍；含镍量为510的次之，为纯锌镀层的23倍。在国外，以Zn—Ni合金代替传统的镀锌和镀锡钢板已实际应用，并获得了很好的防腐蚀效果9，受到普遍的重视。20世纪70年代开始，日本和其他一些国家大量研究了钢基体上电镀Zn—Ni合金的工艺，其电镀溶液多采用简单盐溶液，如硫酸盐或氯化物。由于可以使用较高的电流密度，使生产效率大大提高。90年代后，我国的研究者也展开了大量的Zn—Ni合金电镀的研究工作10-1