Ive done it with silicone bronze wire. dcen tig. mig may work too if its not to thin.
Have you tried the 15 % Silver -Phosphorus -Copper ( Sil - Fos 15 ) applied by TIG ?
That is how we put the copper tubing on to stainless steel for diffusion pumps -
Robert
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Thickness of each part.
intended service etc.
There are many different ways (just as you listed) some are better than others depending on what the intended service of the part is.
Can't "weld" copper to stainless unless you want to fight severe cracking problems. It can be TIG "braze welded" using silicon bronze commonly called Everdure. We do it all the time here at work and have few if any problems. If you Google it you will find some articles about how it was used to build stills during the prohibition era. Now it is used to build micro breweries.
Yes, and Everdur is also called Herculoy, but the Sil Fos as Ravi suggested and Phoson are also doable.
we always used silver solder at the industrial refrigeration fabrication shop I used to work at, of couse we brazed it.