Stainless steel rods on mild steel?

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Hey guys, I gave away some stainless steel rods a while ago, but on the weekend found a box that I had forgotten about. I'm unlikely to ever want to weld stainless. Is there a problem using them on the mild steel I typically weld?ScottYeah, I carry.House keys, wallet, some change, usually a newspaper, maybe a pen.
Reply:They need to be at least 12% Nickel to enable this to work, eg: E309. Fully austenitic types are also OK, eg: E310, E312E316, E308 cannot cope with the carbon steel dilution, often resulting in cracks, or crack prone welds under loading conditions.
Reply:Ah, I knew it wouldn't be that simple. I'll see what it says on the pack.Yeah, I carry.House keys, wallet, some change, usually a newspaper, maybe a pen.
Reply:as stated E309 is a great rod for welding dissimilar metals.
Reply:Okay, I've written down what it says on the pack and it means nothing to me:347 Stainless.Low carbon niobium bearing stabilized stainless steel electrode for stainless steel types AISI, 321, 347 and unstabilized types 301, 302, 304, 304L and 308.Yeah, I carry.House keys, wallet, some change, usually a newspaper, maybe a pen.
Reply:Here's the chemistry from a McKay 347 stainless electrode, and more importantly the AWS specs for chemistry in this filler metal:Typical Chemistry                                     AWS specCarbon (C) 0.06                                        0.08 maxManganese (Mn) 1.19                               0.5 to 2.5Phosphorus (P) 0.026                               0.04 maxSulphur (S) 0.025                                     0.03 maxSilicon (Si) 0.46                                        0.90 maxCopper (Cu) 0.10                                       0.75 maxChromium (Cr) 20.24                                  18.0 to 21.0Nickel (Ni) 10.00                                        9.0 to 11.0Molybdenum (Mo) 0.09                               0.75 maxColumbium (Cb) 0.60                                   8.0 x % carbon minimum to 1.00 maxPer ChrisPC66's comment about nickel content, these are probably not a good choice for welding mild steel.  They've got a lot of chromium and some, but not a lot, of nickel.  Odds are good that you'll get brittle welds if you use these rods to join mild steel.In the description, the word stabilized vs unstabilized refers to the Columbium(aka Niobium) content.  347 contains this element to reduce chromium carbide precipitation; which causes a loss of corrosion resistance. 321 stainless contains titanium instead of columbium, but both elements are added for the same purpose.  The other stainless grades mentioned do not contain either of these stabilizing elements. Originally Posted by scott brunsdonOkay, I've written down what it says on the pack and it means nothing to me:347 Stainless.Low carbon niobium bearing stabilized stainless steel electrode for stainless steel types AISI, 321, 347 and unstabilized types 301, 302, 304, 304L and 308.
Reply:Thanks for taking the time to write that all down. Friends of mine think I'm nuts when I tell them that there is alot to know about metal and welding.ScottYeah, I carry.House keys, wallet, some change, usually a newspaper, maybe a pen.