Toshiba ceramic IC chips

[spartan9]

Has anyone had any experience refining any chips of this variety? I have over 20 of these chips but I can't figure-out what the white metal plating is composed of. I thought if I was lucky it would be palladium but probably more likely some other white metal that does not tarnish. They all have a very high luster. They were removed from old DEC servers from the early 1980's.

Thanks

 

[goldsilverpro]

Unless there is a technical reason why Pd is required above all less expensive metals, there will be no Pd on these parts. This is a good rule to remember for all PMs. The designers aren't stupid. They don't use valuable metals unless there is an absolute need to do so. If anything cheaper will work, they will use it. These parts aren't made to last forever. If you can't think of a good intelligent reason why they would have to use Pd on this particular application, instead of something cheaper, it most probably isn't Pd.

 

[EDI Refining]

My guess is nickel plated steel, or kovar

put a magnet up againist it.

 

[Scott2357]

Although I'm not 100% sure, I suspect Peter may right. I've been doing some experiments with different mixtures of AP. So a few days ago, just for fun, I threw a couple in some AP. The solder seal dissolved as I expected but the lid didn't seem effected for several hours. It eventually turned a dark grey color and formed a layer of dark grey powder easily rubbed off after 2 or 3 days. Underneath the dark grey powder it had a rough but very bright silvery finish. The lid is magnetic as well as the pins, so there is some steel in there somewhere.

 

[goldsilverpro]

Steel, or Kovar.

 

[spartan9]

I have 5 boards in total of the same type designed by DEC. On two of the boards, an LSI gold-plated chip set is used and on one board a Toshiba/LSI combination is employed. The other two boards use the Toshiba set as pictured.

Thanks for all of the responses.