Caracterização do cordão na soldagem FCAW com um arame tubular básico

Abstract

This paper studies the effect of operational conditions on bead shape characteristics in FCA welding with a Brazilian made wire with basic flux (ASME SFA-5.20: E71T-5/E71T-5M) of 1.2 mm diameter. Bead-on-plate downhand welding trials were performed on 12 mm thick low carbon steel plates with a constant voltage power supply. A digital data logging system was used to measure the welding current and voltage, and wire feed rate. While the shielding gas composition (75%Ar-25%CO2 and 100%CO2), wire polarity and feed rate (7 and 9 m/min) were varied during the trials, the electrode extension (16 mm) and arc length (3.5 mm) were not changed. Weld bead characteristics (penetration depth, width, and fused and deposited areas), the presence of discontinuities, bead microstructure and hardness were evaluated. Welding conditions of high productivity (high deposition rate) associated to adequate bead characteristics were determined for the wire.