In article , Harold and Susan Vordos says...


I encountered the cad filled ones occasionally. It blended so well with the
silver that you weren't aware of its presence, yet there was a loss in
weight when the overall mass was processed. Had to be Cd. I can't help
but think that they were in better quality house switches and other light
duty devices. It's been too long to remember.

These were contacts for circuit breakers for GTE's product line.

Back in the early 80s there was a realization that putting a lot
of cadmium in products like that was a bad idea, even if it made
the breakers (contacts) work really well.

When breakers close they don't dry switch, there's a period when
they have to arc a bit to make good contact for passing high
current. My understanding is that somehow the Cd would flash on
opening, and make it easier to close for the next cycle.

They were trying to replace them with the above-mentioned Ag/Wo
sintered contacts I think. The shop was very good at pressing
and sintering stuff.

The guy doing the research ironically lived in Woburn, Mass, which
was the town that had its wells all contaminated by WR Grace, et al.
He used to bring his drinking water home from the lab in a gallon
jug every night. I thought it was ironic anyway, here was a guy
working to eliminate a toxic metal from a product, but at the same
time he had to deal with corporate irresponsibility in a very
concrete fashion.

Jim


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