From searching posts on this forum, I gather that there is no particular source for filler metal selection for dissimilar metals, and is left to designer discretion. I understand that the selection of filler is usually based on the higher strength material and chemistry should closely match that.

In my case, I'll match the Inconel, which from my experience would usually be a Inconel-82 or -625 filler. How would you understand when to choose one over the other for any given situation? I don't have process info, but could get it.