Henning wrote: I’m worried that coating the expensive tungsten electrodes with silver will make them worthless.
Wouldn’t it be better to mill cheaper copper electrodes and coat them? Copper is easier to handle anyway. Or any other easily millable metal.
As I understand, the surface evaporates, so the underlying material is unimportant. Or am I wrong?
Yes it will delay the experiments further, and will cost several thousand dollars.
Erm, now I remember why a non tungsten-cathode is a bad idea. Firstly the sawtooth at the inner rim next to the insulator needs to be tungsten, otherwise they will evaporate too quickly. Secondly the cathode should be monolithic. So these two factors rule out a copper cathode. With beryllium it’s another issue, as it’s melting point is higher.
