氨基磺酸镍电铸层产生针孔、麻点的原因分析及工艺改进

Analysis of formation causes of pinhole and pit in sulfamate electroformed nickel coating and process improvement

通过对比试验对润湿剂、金属离子杂质、有机物杂质、槽液pH以及固体颗粒物等因素进行排查,得出氨基磺酸盐电铸镍层产生针孔、麻点的原因,并提出相应的工艺改进措施。槽液中存在固体颗粒和槽液pH不在工艺范围内是造成镀层表面针孔和麻点的主要原因。为保证产品质量,电铸时应采用精密循环过滤系统对电铸槽液进行连续净化并控制槽液pH在允许的工艺范围内。

The causes of pinholes and pits formation in nickel coating electroformed from sulfamate bath were found out through investigating the factors including wetting agent, metal ion impurities, organic impurities, bath pH, and solid particles by contrast experiments. Some corresponding process improvement measures were proposed. It is indicated that the main reasons for the formation of pinholes and pits in coating are the existence of solid particles in bath and beyond-process-range bath pH. It is essential not only the electroforming bath be purified continuously using sophisticated filtration system, but also the bath pH be controlled in the administrated process range to ensure the quality of products.