Effect of dynamic wire in the GTAW process: Microstructure and corrosion resistance

Riffel, Kauê Correa; Silva, Régis Henrique Gonçalves e; Haupt, William; Silva, Luiz Eduardo da; Dalpiaz, Giovani

doi:10.1016/j.jmatprotec.2020.116758

Cited by 6 publications

(5 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, in the presented procedure, the overlapping of the melted regions is already tight, as the fusion lines that delimit the root of the bead in Figure 7 are overlapping by a small margin. To increase the welding speed, it is necessary to have a proportional increase in frequency, as analytically deduced by Equation (7). Thus, the welding speed was increased to 3.0 mm/s (18 cm/min) and the frequency was incremented to 2.5 Hz, maintaining the duty cycle of 50%.…”

Section: Resultsmentioning

confidence: 99%

“…The pulse and base currents were 50 A and 10 A, respectively. Then, a frequency of 2.5 Hz was tested while maintaining the same duty cycle of 50%, reducing tp and tb to 0.2 s. In this test, the speed and frequency were correlated using Equation (7), increasing the welding speed to 3.0 mm/s (18 cm/min). The welding power source was an IMC model Digiplus A7 600A [23] and the process was automatically carried out using a cartesian robot SPS model Tartílope V4 [24].…”

Section: Methodsmentioning

confidence: 99%

“…where C is the length of the weld bead and n is the number of periods T, corresponding to each weld point. Combining Equation (4) with Equation (3), we obtain Equations ( 5) and (6).…”

Section: C1 = L + (L − S)mentioning

confidence: 99%

“…As n grows without bound, the term 1 − 1 n tends to 1, and the welding speed equation can be simplified to Equation (7).…”

Section: C1 = L + (L − S)mentioning

confidence: 99%

“…Therefore, the isolated analysis of the pulsed current benefits is not an easy task and needs very well-established criteria in order to avoid attributing the cause of a certain property to a factor not directly linked to the manipulated variables [5]. Another example of this synergistic effect that a change in the characteristics of the GTAW welding technique can produce on the weld bead and its properties is also shown by Riffel et al [6] and Silva et al [7].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

A Contribution to the Analysis of the Effects of Pulsed Current in GTAW Welding of 1-mm-Thick AISI 304 Sheets

Dutra

Riffel

Silva

et al. 2023

Metals

View full text Add to dashboard Cite

GTAW welding with pulsed current has been misinterpreted in some of the classic literature and scientific articles. General conclusions are presented, stating that its use provides greater penetration compared to the use of constant current and that the simple pulsation of the current promotes beneficial metallurgical effects. Therefore, this manuscript presents a critical analysis of this topic and adopts the terminology of thermal pulsation for the situation where the weld undergoes sensitive effects, regarding grain orientation during solidification. For comparison purposes, an index called the form factor (ratio between the root width and the face width of the weld bead) is adopted. It is shown that the penetration of a welding with pulsed current can be worse than constant current depending on the formulation of the adopted procedure. Moreover, metallurgical effects on solidification, such as grain orientation breakage, only occur when there is adequate concatenation between the pulsation frequency and the welding speed. Finally, a thermal simulation of the process showed that the pulsation frequency limits the welding speed so that there is an overlap of the molten pool in each current pulse, and continuity of the bead is obtained at the root. For frequencies of 1 Hz and 2.5 Hz, the limit welding speed was 3.3 mm/s and 4.1 mm/s, respectively.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

“…where C is the length of the weld bead and n is the number of periods T, corresponding to each weld point. Combining Equation (4) with Equation (3), we obtain Equations ( 5) and (6).…”

Section: C1 = L + (L − S)mentioning

confidence: 99%

“…As n grows without bound, the term 1 − 1 n tends to 1, and the welding speed equation can be simplified to Equation (7).…”

Section: C1 = L + (L − S)mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations