Stick welding mild steel to SS

They recommend using stainless rod for this.

I had the same situation once. I did weld stainless to mild, with

6013. The weld holds, but there is almost no stress on the weld, this is a part of a cable hanger assembly for my welder and holds 20 lbs at most (welding pedal and angle grinder live on this shelf). i

The recommendation is to use a rod with a higher chrome/nickel content than the stainless.

Where are you located? I could mail you a few rods.

Dan

What this is about, is I'm building slip rolls & the 1/2" mild pieces are the ends & the SS are the bottom mounting plates (they're SS only because that's what I had). The forces on the welds will be from my pulling on the roll lever. Not that much, but if the welds were brittle, say, it'd be a pain to rebuild it.

What I've heard here & Googling the archives is that SS rod is really the way to go. But I did a test - welding up the same material. I put about 3/4" of bead on each side & a bead across the end (1/2"). I welded a 24" piece of 1" bar to the 1/2" plate, for leverage.

To test it I put the SS plate in the vice & pulled on the 1" bar (actually, I supported my 190lbs on it). As far as strength - no problem, I probably put 400 - 600 lbs tension on it. As far as the brittleness, I took a rBFG (6lb sledge) & beat on it - no problem. When I took the test apart I cut the weld on one side & bent the piece back over the weld on the other side. That weld broke in the middle of the bead (did not tear out of either piece).

I don't doubt that SS rod is the proper way to go & in a commercial situation that's what I'd use. But in this HSM context, I'm going with the 6013.

Thanks for the replies, Bob

Thanks - the offer is much appreciated. Per my other post, I'm going with the 6013 & won't need to take you up on the SS.

Thanks, Bob

Never done it myself, but from a welding engineer

Weld with a high enough Cr and Ni rods that with weld dilution still end up with austenitic weld metal.

So mixture of the rod composition, the stainless plate and the mild steel plate (essentially pure iron) gives a pool metal still above about 18%Cr 8%Ni.

Isn't there a stainless composition about 25%Cr 18%Ni whose rods are favourite for this type of job?

Richard Smith

:

=A0 =A0 =A0 =A0 =A0 Dan

309 22-24 % cr. 12-15 nickel

312 30% cr. 9 % nickel

Dan

Ooops - apologies - 309 already mentioned. Rich S