http://i11.photobucket.com/albums/a189/vdubin474/Laddercrack1.jpg http://i11.photobucket.com/albums/a189/vdubin474/laddercrack2.jpg http://i11.photobucket.com/albums/a189/vdubin474/laddercrack3.jpg You are looking at a crack along the toe of a weld. This is a handrail support tube welded to a beam. Handrail support is of a GLX-55 material and a thickness of .060" and the beam is of a A607 material and with a thickness of .075". It is first MIG welded with a .035 ER802-D2 wire and if there are and defects, they get TIG dressed. As you can see, the one in the picture has been TIG dressed probably because of some overlap in the first weld.
So I'm looking for some thoughts and opinions on why this might of cracked where it did. If you look at the TIG dressing, you can see that little or no filler was used around the toe of the weld. If filler was used, it would be the same as the MIG wire (ER80S-D2). I'm thinking that since no filler was used, the base material got way to hot and hot shorted, causing embrittlement right in the HAZ next to the toe. So what else do you guys think it could be?
Thanks, Kix