Comparison of Arc Stability and Variability of Geometry of Welds Obtained by MIG/MAG and FCAW Processes

Abstract

Despite the similarity, the MIG/MAG and Tubular Electrode processes have particularities regarding the arc stability and variability in the characteristics of beads. Thus, the choice of one of the processes to specific application should consider how such particularities affect the quality of these welds. To support this choice, this study aimed to investigate as change in average current affects the stability and regularity of the metal transfers on welds performed with constant voltage and current pulsed and compare the variability of geometry and dilution of these weld. To achieve these goals automated welds were carried out , based on the metal ABNT 1020 and adding the metal wire ER70S -6 AWS and AWS E71T -1. In addition to the welds with the variation current average, the tests involved the determination of the parameters for the occurrence of stable transfer by short circuit, goticular and pulsed. The results showed that the voltage that determines the greatest stability in the short circuit transfer mode, is independent the welding speed of and increases with the wire speed, also showed that tubular wire solders showed higher variability compared to the solid wire.

Key-words: MIG/MAG; Flux cored electrode process; Arc stability; Variability