Metal cap on processor.

[Makcc]

Please see attached picture.
Any suggestions as to what metal is on the top of the chip?

 

[mls26cwru]

not sure as to the metal, but do you have a picture of the full board?

 

[Makcc]

Here's a picture of the board.
The metal did not react with nitric acid.

 

[g_axelsson]

Probably kovar. Is it magnetic?
You have to match the thermal expansion of the ceramics with the metal or it'll break when thermally cycled.

Göran

 

[Makcc]

It's not magnetic.

 

[g_axelsson]

Maybe stainless then or nickel plated.

Göran

 

[Makcc]

Thank you.
It's soft, bends easily and does not react with nitric..
Bending I think would rule out stainless.
The nitric would have attacked the nickel..

 

[mls26cwru]

I like the board! Do you have another one that is undamaged?