Characterization of dynamic behaviour of short circuit in pulsed Gas Metal Arc Welding of aluminium

Purpose: This paper studies dynamic characteristics of short circuit in the pulsed current gas metal arc welding (GMAW-P). Design/methodology/approach: Welding experiments with different values of pulsing parameter and simultaneous recording of high speed camera pictures and welding signals (such as current and voltage) were used to identify different short circuit conditions in GMAW-P. The investigation is based on the synchronization of welding signals and high speed camera to characterize different types of short circuit occurring in GMAW-P system. The behaviour of short circuit under the influence of different pulsing conditions is also investigated. Findings: It will be shown in the paper that short circuit in GMAW-P occurs in different forms which can be categorized depending upon time of short circuit and phase (peak or base time) of the pulse. Further investigation involves study of the dynamic behaviour of short circuit with variation of different pulsing parameters. Research limitations/implications: The results show that by varying the pulse parameters, behaviour of short circuit in GMAW-P is changed. The pulse parameters can be adjusted to avoid occurrence of short circuit in GMAW-P. Future work should concentrate on development of practical indices in terms of pulse welding parameters for quantitative estimation of short circuit occurrence and avoidance. Originality/value: Determination of proper working parameters with GMAW-P is crucial for the appropriate selection of pulse welding parameters. As short-circuiting is common between the welding electrode and the workpiece in GMAW-P, so in order to estimate the working parameters and ensure stable GMAW-P understanding dynamic behaviour of short circuit in GMAW-P will be useful. However, in case of aluminum hardly any attempt is made to analyse the dynamic behaviour of short circuit in GMAW-P. This paper analyses the short circuit phenomenon in GMAW-P and their behaviour with varying pulsing parameters.