Co2 Welding Gas For Stainless Steel. Or Argon Oxygen mixes with less than 5 O2 as alternative shielding gases. Or use stainless steel flux core.
C2 or 2 Carbon Dioxide and 98 Argon. An Ar CO2 blend is also an active gas but less reactive than 100 CO2. Carbon dioxide gives good fusion and penetration characteristics even in positional work.
Some stainless steel welding codes require gas shielding on the back side.
Because of stainless steels poor thermal conductivity and the relatively cool nature of short circuit transfer gas metal arc welding GMAW this process requires a trimix gas that contains a blend of 85 to 90 per cent helium He up to 10 per cent argon Ar. Food service codes for example do not tolerate a bunch of germ trapping crevices in the weld area. The aesthetics of the final piece especially if you are using bead appearance. 33 AUSTENITIC STAINLESS STEEL The austenitic stainless steels contain 16-26 Cr 8-24 Ni Mn up to 040 C and small amounts of a few other elements such as Mo Ti Nb Cb and Ta.