Cadmium Bloom?

[blnorman]

I've received a couple of electronic connectors. There is what appears to be corrosion on the outside (elemental analysis shows much higher carbon content than "non-corroded" areas). Customer wants to know if it's cadmium bloom. Internet search stated that cadmium in contact with organic acids with exhibit this condition. My question, what does cadmium bloom look like, and how would I know from and elemental analysis?

 

[drrust]

Look at zinc bloom. The metals are almost identical in their chemistry and corrosion behavior. Many organizations still prefer cadmium despite the environmental and occupational health concerns, but, for most purposes zinc and cadmium are used based on customer preference.

I recently talked to a California electroplater who told me that customers were still using cadmium, and they supplied it only when the customer insisted.

There's still a market, even though the efforts (based on my personal experience which only goes back to the 1970s) to replace cadmium have been underway ever since the US organized the Federal EPA around 1969.