镀铜或镀铜合金零件在潮湿环境中经常会生褐色或黑色斑。除了潮湿外,材料表面上的多孔性,镀复后马虎的冲洗和在孔隙中残留了能产生氨的镀液,也都是斑点形成的因素。在镀复过程中,气孔中充满了镀液,当条件适宜时,含氰化物溶液首先分解形成 Copper-plated or copper-plated alloy parts often produce brown or black spots in wet conditions. In addition to moisture, the porosity on the surface of the material, sloppy flushing after plating, and residual ammonia-producing bath in the pores are all speckle-forming factors. In the plating process, the pores are filled with a plating solution. When the conditions are favorable, the cyanide-containing solution is first decomposed to form