Introduction: Producing a very clean, low-oxygen weld deposit has long been a goal of welding consumable manufacturers. Basic flux-cored arc welding (FCAW) electrodes of the EXXT-5 designation offer excellent toughness and weld metal cleanliness; however, the operation of most T-5 electrodes is very harsh with high levels of spatter. What’s more, the puddle tends to be too fluid for out-of-position welding. Rutile-based FCAW electrodes, such as American Welding Society (AWS) EXXT-1 and EXXT-12, offer smooth operation and good all-positional capabilities. However, because the weld deposits tend to be relatively high in oxygen, impact toughness will typically be much lower than what can be achieved with a basic slag system. Furthermore, as weld metal tensile strength increases, it is common to see a drop-off in impact toughness. As a consequence, many users will opt for EXX18 shielded metal arc welding (SMAW or “stick”) electrodes to achieve good toughness and all-positional capabilities, thereby sacrificing the high productivity that can be achieved with a flux-cored product.
Hobart® Filler Metals has taken on the challenge of producing a flux-cored wire that provides the excellent toughness and low oxygen levels of a basic flux-cored wire or stick electrode with operability and out-of-position welding capabilities that are closer to those of rutile-based fluxcored wire.
Author: Susan R. Fiore