在 BAg45 CuZn 钎料表面进行化学镀锡,分析镀液温度、pH 值、施镀时间对锡镀层的沉积速率和AgCuZnSn 钎料中锡含量的影响规律,确定最佳工艺,并表征锡镀层的表面形貌和 AgCuZnSn 钎料的润湿性。 分析表明:随着温度和 pH 值升高,镀层沉积速率和 AgCuZnSn 钎料锡含量均先升高,后降低;随着施镀时间的延长,沉积速率先增大,后快速减小,而 AgCuZnSn 钎料 Sn 含量逐渐增大。 采用最佳工艺时,沉积速率达到 13 . 6 μm / h,锡镀层的表面平整、致密度高,所得钎料的 Sn 含量为 2 . 45% ,与基体 BAg45 CuZn 钎料相比,其润湿性有大幅度提高,铺展性好。

The experiment of electroless tin plating on BAg45 CuZn brazing filler was investigated. The effect of plating bath temperature, pH value, plating time on depositing rate and tin content of AgCuZnSn brazing filler were analyzed. The optimal plating conditions were obtained. The surface morphology of tin coating and the wettability of AgCuZnSn brazing filler were characterized. The results indicate that the deposition rate and tin content of AgCuZnSn brazing filler initially increase and then decrease with the increase of bath temperature and pH value. With increasing of the plating time, the plating rate of tin coating also increase firstly and then decrease sharply, but the tin content of AgCuZnSn brazing filler increase gradually. Under the optimized conditions, the tin coating on BAg45CuZn brazing filler is composed of smooth and uniform,then the depositing rate of tin coating is as much as 13. 6 μm / h, tin content of 2. 45% in AgCuZnSn brazing filler. The wettability of the AgCuZnSn brazing filler has greatly improved than the BAg45CuZn brazing filler matrix under the optimal conditions, it possess good spreadability.