tig welding stainless to mild steel can this be done do you need a specail filler rod ?

 

most head flanges are mild steel, meaning stainless is welded to mild all the time

309l rod

 

Will it work with 316 rod?

Sander.

 

Iv always been told welding stainless to mild you want a filler with a higher fn number. 309l is like 13 where 316 is 10. Id just stick with the 309l, plenty of threads about it floating around the intrawebz.

 

Use 309

 

I use 309L for welding carbon steel to 304 or 316. I think it is the right rod for mild to most stainless steels. Welding carbon to ss with 309 is my favorite welds to make.

 

Yes, 309 is an excellent choice for most applications. The ferrite number is important, but isn't the only important factor.
The stainless in question is also important. 309 is not a good match for all 300 series stainless welds to mild steel, and variants exist to address these exceptions. Other times, duplex fillers may fit the bill.

 

Inconel 82 would work too

 

Would 309 be the best bet for 321 to mild as well?