I hope this question is in the right section.
I have a heatsink that consists of both aluminium and copper. It's started to corrode, oxidate etc. I've tried different chemicals (such as HCL, Salt and Vinegar, Coke, and a aluminum brighenter that consisted of hydrofluric acid and sulphuric acid) to get it bright and shiny again - but none seem to do the job. The problem is that the fins are very tighly spaced (a few mm's) so I can't get inbetween them to scrub.
I would ideally like to get it anodized in black, but i've been told copper cannot be anodized, is this correct?
I took it to a company that does electroplating but was told that the nickel wouldn't go inbetween the fins - they said electroless nickel might work, but they didn't have the means to do it. Should I bother ensuing this method? Also because copper and aluminium are treated/cleaned in different ways prior to electroplating, the acids used may cause a problem.
Powder coating is another option, but i'm not sure how this would affect the heasinks perfomance. What's the heat conductivity of a thin layer of powder coating? Bad, right? Also would it work, or would the powder simply be attracted to the egde of the fins instead of coating it evenly?
Lastly I thought of sand blasting it. Would this damage the heatsink in anyway? I've also seen tiny glass beads being used instead of sand, would this be a better option?
Sorry, lots of questions! I would really appreciate any answers. Thank you!