SUBMERGED-ARC FILLET WELDS BETWEEN MILD-STEEL AND STAINLESS-STEEL

Submerged are fillet welds between mild steel and Type 304 stainless s teel, made with ER309L wire, may contain no ferrite and be at risk of hot cracking, or they may be sufficiently diluted that they transform to martensite with both hot cracking risk and low ductility. This situ ation is most prevalent when direct current electrode positive (DCEP) polarity is used and when the flange is the mild steel part of the T-j oint. A flux that adds chromium to the weld can somewhat alleviate thi s tendency. Direct current electrode negative (DCEN) polarity greatly reduces this tendency by limiting dilution. Fillet weld compositions a nd dilutions are obtained for a number of welding conditions and fluxe s.