镀锡扁铜线发展现状及微细扁线镀锡工艺初探

Current development of tin-plated flat copper wires and preliminary study on tin plating process of flat micro-wires

介绍了镀锡扁铜线的主要特点及加工难点,概述了国内外镀锡扁铜线的研究现状。评述了热镀、电镀、化学镀3种常用镀锡方法的优缺点。建议采用化学镀法对微细扁铜线进行镀锡。描述了3种化学镀锡方法(包括还原法、歧化法和浸镀法)的反应机理及特点。提出了一种化学浸镀锡工艺,其流程包括除油、活化、镀锡、烘干等,镀液配方为:SnCl225～30g/L,NH2CSNH280～120g/L或CH3HSO35～8g/L,NaH2PO2·H2O60～100g/L,OP乳化剂2mL/L,对苯二酚2～5g/L。分析了该工艺的可行性。

The main features and machining difficulties of tin-plated flat copper wire were introduced, and its current research status at home and abroad were summarized. The advantages and disadvantages of hot dipping, electroplating and electroless plating for producing tin coatings were evaluated. Electroless plating was recommended for tin plating on micro flat copper wires. The characteristics and reaction mechanism of three kinds of electroless tin plating methods, including reduction, disproportionation and dip coating, were described. An electroless tin plating process was proposed with the following flow： degreasing, activation, electroless plating, and drying. The bath is composed of SnCl2 25-30 g/L, NH2CSNH2 80-120 g/L （or CH3HSO3 5-8 g/L）, NaH2PO2·H2O 60-100 g/L, OP emulsifier 2 mL/L, and hydroquinone 2-5 g/L. The feasibility of the process was analyzed.