中文摘要：

为解决印刷线路板传统锡-铅合金电镀工艺的铅氟环境污染问题,对硫酸亚锡-β-萘酚酸性纯锡电镀工艺进行了研究。采用赫尔槽法、人工加速腐蚀法、SEM、XRD等方法测定了镀液各组分对镀液性能及镀层质量的影响。得到该体系适宜的工艺条件：硫酸亚锡30 g/L,硫酸70 mL/L,β-萘酚0.5 g/L,明胶1 g/L,1~3 A/dm2,25~35℃,15 min。在此条件下施镀,可得到光滑平整的半光亮镀锡层。镀液性能测试表明：其分散能力可达到93.51%,深镀能力L/Φ至少可到5,电流效率可达97.8%。SEM实验表明：该体系得到的镀层结晶致密、均匀,晶粒大小约为3~5μm。XRD测试表明：锡在（211）晶面择优沉积。人工加速腐蚀实验表明：镀层耐蚀性能良好。该工艺具有污染小、沉积速率快、成分简单等优点,有望应用于印刷线路板酸性镀锡工业生产。

英文摘要：

The pure-tin plating process in stannous sulfate-β-naphthol system was investigated to overcome the environmental pollution in the traditional tin-lead alloy plating process for PCB.The influences of bath components on the performance of Sn coating and bath were investigated using Hull Cell,manual accelerated corrosion,SEM,XRD,etc.The obtained appropriate process conditions are that SnSO4 is 30 g/L,H2SO4 70 mL/L,β-naphthol 0.5 g/L,gelatin 1 g/L,temperature 25~35 ℃ and current density 1~3 A/dm2.A semi-bright and glossy coating was obtained after plating for 15 min under these conditions.The throwing power of the bath reaches 93.51 %,ability of deep plating of L/Φ reaches 5,and current efficiency reaches 97.8 %.The crystal of coating is superfine and mainly assigned to the（111） crystal face.The corrosion resistance is good.The process may be used for PCB tin plating production due to less pollution and fast deposition rate.