亚铁离子对甲磺酸高速镀锡溶液电化学行为及其镀层的影响  

Effect of Fe^(2+) on electrochemical behavior of methanesulfonic acid electrolyte for high-speed tin electroplating and the tin coating obtained therefrom

作　　者：王志登[1] 王洺浩[1] 王熙禹 黎德育[1] 李宁[1] 

机构地区：[1]哈尔滨工业大学化工学院,黑龙江哈尔滨150001

出　　处：《电镀与涂饰》2015年第20期1139-1144,共6页Electroplating & Finishing

摘　　要：研究了带钢甲磺酸体系高速镀锡工艺中,杂质Fe2+对镀锡溶液电化学行为及其镀层的影响。镀液循环伏安特性和调制动力学行为研究结果表明:Fe2+主要对甲磺酸镀锡液的阴极放电过程有影响,提高了镀液的析氢活性,降低了电流效率,Fe2+在H+和Sn2+的放电过程中不参与沉积。转速>1 000 r/min、Fe2+含量大于5 g/L时,Sn2+电化学反应扩散控制拐点消失,H+和Sn2+的混合反应控制区增宽,析氢电位随转速提高而正移。赫尔槽试验和扫描电镜观察发现:Fe2+不影响镀液的分散能力,但降低了镀液电流效率;Fe2+含量大于15 g/L时,1.1 g/m2锡量的镀锡板的镀层表面粗糙,结晶不均匀细致,Fe2+的存在使镀层孔洞明显增加,镀锡板耐蚀性下降。The effect of Fe2＋ ion on the electrochemical behavior of methanesulfonic acid （MSA） tinning bath used for high-speed tinplate production and on the properties of tin coating obtained therefrom was studied. The cyclic voltammetric characteristics and modulation dynamic behavior showed that Fe2＋ mainly affects the cathodic discharge process of the MSA tinning electrolyte as shown by the improvement of hydrogen evolution activity and the decrease of deposition efficiency, but does not involve in the deposition process. As the rotating rate 〉1 000 r/min and Fe2＋ content 〉5 g/L, the inflection point in the diffusion control zone of Sn2＋ electrochemical reaction is disappeared, the mixed reaction control zone ofH＋ and Sn2＋ is widened. The hydrogen evolution potential is shifted positively with the increasing of rotation rate. It is found by Hull cell test and SEM observation that Fe2＋ has no effect on the throwing power of the tinning bath, but reduces the current efficiency. The tinplate with 1.1 g of tin per square meter obtained at Fe2＋ content 〉15 g/L has a rough surface with non-uniform crystals. The existence of Fe2＋ in the MSA tinning bath increases the porosity of tin coating and decreases the anticorrosion performance of tinplate.

关 键 词：镀锡板 高速镀锡 甲磺酸 亚锡离子 亚铁离子 电化学 微观组织 

分 类 号：TQ153.13[化学工程—电化学工业]