Estudo exploratório da influência dos picos de corrente de soldagem na estabilidade do processo de soldagem GMAW curto-circuito

Abstract

The stability of the welding arc has been studied in different ways, to better understand the influence of the parameters on the final quality of the process. Thus, there are researches that seek, through statistical analysis of the current and voltage signals of reignition of the welding arc, evaluate such stability. Histograms and statistical calculations of open arc time parameters and short circuit time are important means of assessing the stability of the welding processes. However, in the statistical study of stability, the issues related to the distribution of current peaks during the electric arc welding process have not been fully explored. Thus, this work proposed to perform an exploratory study of the distribution of current peaks during the electric arc in the GMAW-CC process, by varying the wire feed rate. Such studies were carried out using statistical methods, such as chi-square and standard deviation, seeking to define a speed value that could guarantee the statistical similarity between the weld beads. The current signals used in the work were evaluated using an algorithm developed in Matlab©. Thereby, it was possible to identify, during the work, the speed of 3.5 m/min as a value that can be considered optimal. Moreover, it was observed that for speeds between 3.3 and 3.8 m/min the standard deviation values of the current were similar.