Current mode effects on weld bead geometry and heat affected zone in pulsed wire arc additive manufacturing of Ti-6-4 and Inconel 718

Abstract

For the last decade, additive manufacturing (AM) has been revolutionising the aerospace industry, building and repairing various components for aircrafts and outer space vehicles. Despite the fact that AM is gaining rapid adoption by the industry, it is still considered a developing technology, with ongoing research in a variety of fields. Wire arc additive manufacturing (WAAM), a welding-based AM technology, is an active field of research as well, because it enables economical production of largescale metal components with relatively high deposition rates. In this article, the effects on the weldbead geometry and heat affected zone from high and low frequency pulsed current are explored on Gas Tungsten Arc Welding (GTAW). The materials used in this investigation were selected to be Ti-6-4 and Inconel 718, both highly used in the aerospace industry for their high strength-to-weight ratio and strength at elevated temperatures respectively. The design of the experiments followed a Taguchiinspired orthogonal array, altering, apart from the current modes and values, the torch travel speed driven by an industrial robotic arm as well as the wire-feeding rate.The results demonstrate the ability to control both the weld-bead dimensions and penetration depth, as well as the heat affected regions, by utilizing the dual pulsing combination of both high and low frequency pulsing. Alterations from wide beads with deep penetration to narrower beads with greater height-to-width ratios are demonstrated in a single manufacturing setup, enabling further development of the WAAM process.

Multiphysics modelling of Gas Tungsten Arc Welding on ultra-thin-walled titanium tubing

“…However, as a broader novelty there is experimental evidence explored in detail in [134] that supports the view that InterPulse limits the heat input when welding commercially pure titanium in a way consistent with a focused heat input due to arc constriction. There is also experimental support for the benefits of InterPulse in other welding procedures [135,136].…”

Parametric Optimisation of Micro Plasma Welding for Wire Arc Additive Manufacturing by Response Surface Methodology

“…5(a) shows that 𝑣 has the most significant influence on W. The lower the 𝑣, the wider the W produced. The combination of the lowest 𝑝 and 𝑓 with the slow welding speed resulted in higher heat input and, as a result, a larger melt pool dimension produced [24,25]. Fig.…”

Effect of Process Parameters on Arc Behavior and Weld Formation in Weaving Gas Tungsten Arc Welding

“…It was the result of the action of the weaving arc and rarely suffered from undercut defects. Since the weaving arc can slow down the solidi cation process of the metal at the edge of the molten pool and eliminate the obstruction of metal expansion in the middle of the molten pool, it is bene cial to improve the spreadability of the weld surface for the Sshape weld obtained in weaving GTAW welding [22]. An increase in weave angle, weave speed, and weave stop time increased the weld width and the number of crescent shapes of the weld, and widened each crescent for the same weld bead.…”