Assessment of arc stability features for selected gas metal arc welding conditions

Abstract

Stability is a key indicator of the efficiency of the gas metal arc welding operation, and it is linked to other quality indicators like spattering and weld formation. This study describes methods of assessing arc stability for selected gas metal arc welding (GMAW) conditions. It focuses on stability characterization and defines the relationship between process stability and influencing factors. Welding tests were performed using two selected transfer modes the spray and the pulse transfer modes to characterize stability and develop processes further for better overall performance. This scope of parameters was selected to simulate certain range of stability behavior, so it was possible to analyze the factors correlated to stability, their relevance in influencing stability, and consequently to define a calculation algorithm for the determination of stability. Also, stability was calculated and scored based on two scoring indices. With a higher voltage, disturbance levels were noticed to reduce as in the case of 29 V, 31.5 V, and 32.5 V with 32.5 V showing better stability to spattering, smoothness, repeatability, and regularity of the process. Actual values of positive and negative voltage peaks, voltage amplitudes, and their average values and standard deviations in selected analyzed time showed to be relevant indicators to characterize stability of the process. Variations of indicated voltage signals related to explosions showed to have complex patterns in terms of their waveforms. So, all these were analyzed step by step and consequently selected for characterization in the welding conditions that were selected in the scope of this study.

Effects of Contaminations on Electric Arc Behavior and Occurrence of Defects in Wire Arc Additive Manufacturing of 316L-Si Stainless Steel

“…The stability of the welding arc is often analyzed using power graphs, commonly referred to as cyclograms, which depict the voltage against the electric current intensity [45]. These graphs offer straightforward insights into deposition stability, facilitating a rapid assessment of process outcomes [31]. A smaller area under the curve indicates a more stable metal transfer process [46].…”

“…Figure 5 illustrates the current and voltage histograms for layers 2 To describe and improve the accuracy of the arc stability analysis, the arc current deviation histograms were built, as they show the deviation of the signals during the entire acquisition period. The width and height of these diagrams are reliable indicators of arc stability [31,47]. An arc deposition process exhibiting a tall, narrow peak demonstrates a more stable arc [30].…”

“…Authors have studied the stability of the electric arc for arc deposition processes and, in this perspective, have applied numerical indicators to quantify it. In the context of short-circuit deposition processes, the Vilarinho index (IVsc) has been applied to study the mechanism of this transfer mode in GMAW [31][32][33][34], in stability analyses of the cold metal transfer (CMT) in brazing processes [35], and in the optimization of its parameters in the WAAM process [36]. However, the use of the IVsc to verify the stability of the arc as a function of introducing defects in the arc deposition processes has not yet been explored.…”

Effect of Exothermic Additions in Core Filler on Arc Stability and Microstructure during Self-Shielded, Flux-Cored Arc Welding

“…This preheating enables the electrode to burn off faster and increases the deposition rate [77]. It has been concluded that the welding consumables, welding parameters, and equipment have a key role to play in the stability of the welding process [78][79][80][81].…”

Investigation of the arc stability during self-shielded flux-coed arc welding with exothermic additions

“…The main welding parameters characterising the stability of the process are welding current (wire feed speed) and arc voltage [32]. Kah et al [32] showed the existence of a relationship between voltage fluctuations and explosions that occur during metal transfer. Thus, knowledge of arc voltage and welding current are important parameters in hardfacing and require special study in the development of new filler materials.…”