I am developing an electrical device which uses a machined piece of copper for an electrical conductor. This is done for packaging efficiency. Because the machining process leaves some sharp edges and burrs, I thought I would soak it in Ferric Chloride to remove these prior to insulating. I've performed a few soaking tests on some sample strips of copper and am a little puzzled by the results. Although the Ferric Chloride is removing the burrs and sharp endges, it is also leaving a dark, grayish film on the copper. I was expecting to see a nice shiny piece copper come out of the etchant, once washed off. But that isn't the case as all. If I look at the surface under magnification, it looks very rough. This leads to my questions.
1. What is this film? Some by product of the etching reaction?
2. Is there a better etchant to use for what I'm try to accomplish? I was hoping to remove burrs and round edges, as well as clean the copper surface with this soaking process. That way the part would be ready for insulating without needing any further treatment. But at this point it's not looking too promising.
Thanks for any help with this. I appreciate it.
Pat
1. What is this film? Some by product of the etching reaction?
2. Is there a better etchant to use for what I'm try to accomplish? I was hoping to remove burrs and round edges, as well as clean the copper surface with this soaking process. That way the part would be ready for insulating without needing any further treatment. But at this point it's not looking too promising.
Thanks for any help with this. I appreciate it.
Pat