This question has already been asked in the last day or two.
NOT ENOUGH DATA... and a poor question to boot.
ER11019 1/8" Would tell us (by AWS standards) that you are talking about bare solid wire of some sort, with a 110Ksi strength. (I have no idea what the 19 would represent)
Is this a GTAW weld with 1/8 inch filler?
is the SAW with the rod also being used as the electrode?
Or ... Are you asking something altogether different?
If you are... You need to provide.. base metal, *WELDING PROCESS*, material thickness, preheat, interpass, post heat.
How was it tested.. According to which code? Bend radius ?
more more more
If it was not operator error, then there are a multitude of possible reasons. However, there is not enough info to narrow it down and some of the info provided does not jive. "ER" indicates a bare wire electrode that could be used for GTAW, GMAW or SAW, but the "11019" part is similar to a coated SMAW electrode. Also, the last number would be the coating type, but there is not a "9" coating unless this is a recent change to AWS A5.5.
The 110 series of electrodes are typically used on quenched and tempered steels. Possible failure modes for a bend specimen are trapped slag, incomplete fusion, incomplete penetration, excessive heat input, insufficient preheat, excessive interpass temperature, excessive porosity, underbead cracking, weld metal hardness significantly greater than base metal hardness, and probably a few others. Please provide more information on the base metal specification, welding process, correct AWS classification for the electrode, welding position, preheat, maximum interpass temperature, welding position, plate thickness, type of bend (face/root or side bends), etc.