do I need to do a charpy v notch test on Inconel 625 tubes that are .007 thk and .010thk at -423
and then we weld to to a prepped fitting 316l and the edge is .020 thick at -423
my customer is asking for charpy test even on the filler rod at -452
To what spec or code?
These austenitic alloys are usually exempt from impact requirements.
What filler are you using?
It would be more informative to conduct some sort of cold deformation test on a sample part.
These are way too small for any meaningful impact testing.
You could perform an all weld metal Charpy test by making a weld coupon of sufficient thickness with the chosen filler metal but what it would accomplish is somewhat meaningless to the actual welds being made.
And why on earth would you think that 316L is a good filler for this weld?
I first presumed that it would be autogenous.
You do have to be a little careful, if your 316 has too high FN you can loose some ductility at low temps.