Heating a strip electrode with welding current in arc welding with a stationary consumable electrode

2004 ◽  
Vol 18 (2) ◽  
pp. 145-150
Author(s):  
V O Bushma
Keyword(s):  
Arc Welding ◽  
Welding Current ◽  
Consumable Electrode ◽  
Strip Electrode

Application of pulsed impact in consumable electrode gas-shielded arc welding (Review)

2019 ◽  
Vol 2019 (8) ◽  
pp. 30-40
Author(s):  
V.A. Lebedev ◽  
◽  
S.V. Dragan ◽  
G.V. Zhuk ◽  
S.V. Novikov ◽  
...  
Keyword(s):  
Arc Welding ◽  
Consumable Electrode ◽  
Gas Shielded Arc Welding

scholarly journals Effects of robotic CO2 arc welding variables on penetration and microstructure of weld in C-80 grade steel

2010 ◽  
Vol 7 (1) ◽  
pp. 67-75
Author(s):  
Hamid Reza Ghazvinloo ◽  
Abbas Honarbakhsh-Raouf ◽  
Nasim Shadfar
Keyword(s):  
Weld Metal ◽  
Cross Sections ◽  
Arc Welding ◽  
Welding Process ◽  
Welding Current ◽  
Residual Austenite ◽  
Martensite Phase ◽  
Optical Observations ◽  
Bead Geometry ◽  
Steel Joints

Generally, the quality and properties of a weld joint is strongly influenced by welding variables during process. In order to achieve an ideal weld, it is important attention to bead geometry and microstructure evolution of weld metal. The effect of process variables on penetration and microstructure of C-80 steel joints produced by robotic CO2 arc welding was studied in present work. Different samples were produced by employing arc voltages of 23, 25 and 27 V, welding currents of 100, 110 and 120 A and welding speeds of 42, 62 and 82 cm/min. After welding process, geometric measurements were performed on welding specimens and the microstructural evolutions were investigated by optical observations of the weld cross sections. Results were clearly illustrated that increasing in welding current or arc voltage increases the depth of weld penetration. The highest penetration in this research was observed in 62 cm/min welding speed. The metallographic examinations also indicated that the microstructure of weld metal in all of specimens was composed mainly of martensite (M) and residual austenite (A) phases that a portion of martensite phase had been tempered.

scholarly journals Relationship among Welding Defects with Convection and Material Flow Dynamic Considering Principal Forces in Plasma Arc Welding

Metals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1444
Author(s):  
Huu Loc Nguyen ◽  
Anh Van Nguyen ◽  
Han Le Duy ◽  
Thanh-Hai Nguyen ◽  
Shinichi Tashiro ◽  
...  
Keyword(s):  
Weld Pool ◽  
Material Flow ◽  
Arc Welding ◽  
Welding Current ◽  
Plasma Arc Welding ◽  
Plasma Arc ◽  
Flow Dynamic ◽  
Pool Surface ◽  
Welding Defects ◽  
Marangoni Force

The material flow dynamic and velocity distribution on the melted domain surface play a crucial role on the joint quality and formation of welding defects. In this study, authors investigated the effects of the low and high currents of plasma arc welding on the material flow and thermodynamics of molten pool and its relationship to the welding defects. The high-speed video camera (HSVC) was used to observe the convection of the melted domain and welded-joint appearance. Furthermore, to consider the Marangoni force activation, the temperature on the melted domain was measured by a thermal HSVC. The results revealed that the velocity distribution on the weld pool surface was higher than that inside the molten weld pool. Moreover, in the case of 80 A welding current, the convection speed of molten was faster than that in other cases (120 A and 160 A). The serious undercut and humping could be seen on the top surface (upper side) and unstable weld bead was visualized on the back side (bottom surface). In the case of 160 A welding current, the convection on the weld pool surface was much more complex in comparison with 80 A and 120 A cases. The excessive convex defect at the bottom side and the concave defect at the top surface were observed. In the case of 120 A welding current, two convection patterns with the main flow in the backward direction were seen. Almost no welding defect could be found. The interaction between the shear force and Marangoni force played a solid state on the convection and heat transportation processes in the plasma arc welding process.

Application of a Front Tracking Method in Gas Metal Arc Welding (GMAW) Simulation

2004 ◽  
Vol 127 (3) ◽  
pp. 590-597 ◽  
Author(s):  
Guo Xu ◽  
William W. Schultz ◽  
Elijah Kannatey-Asibu
Keyword(s):  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Welding Current ◽  
Front Tracking ◽  
Front Tracking Method ◽  
Surface Method ◽  
Metal Arc Welding ◽  
Initial Drop ◽  
Velocity Pressure ◽  
First Time

A numerical model is developed to simulate the short-circuiting metal transfer process during gas metal arc welding (GMAW). The energy equation and the Marangoni convection are considered for the first time in analyzing the short-circuiting time. A front-tracking free surface method explicity tracks the profile of the liquid bridge. The electromagnetic field, distribution of velocity, pressure, and temperature are calculated using the developed model. Effects of welding current, surface tension temperature coefficient, and initial drop volume on short-circuiting duration time are examined. The results show that both the electromagnetic force and Marangoni shear stress play significant roles in short-circuiting transfer welding.

Structure and Crack Resistance of N-A-XTRA-70 Steel Joints Manufactured by Hybrid Laser-Arc Welding

2018 ◽  
Vol 927 ◽  
pp. 29-34 ◽  
Author(s):  
V. Pozniakov ◽  
L. Markashova ◽  
O. Berdnikova ◽  
T. Alekseienko ◽  
S. Zhdanov
Keyword(s):  
Crack Resistance ◽  
Welded Joints ◽  
Arc Welding ◽  
Structural Phase ◽  
Consumable Electrode ◽  
Phase Changes ◽  
External Loading ◽  
Hybrid Laser Arc Welding ◽  
Source Power ◽  
Scanning Electron

Crack resistance of welded joints is one of the most important indices of service reliability of critical designation structures. The purpose of the research is the establishment of the influence of technological modes, hybrid laser-arc welding of high strength steel NA-XTRA-70 on the formation of structure in the metal welded joints, as well as analysis of the influence of this structure on their crack resistances. For the experiments the laboratory setup has been developed on which the experiments were carried out in the technological scheme that provides the location of the consumable electrode arc at a certain distance in front of the laser beam in the welding direction. Nd: YAG-laser DY 044 of company ROFIN (Germany) was a laser radiation source. Power for consumable electrode arc was carried out by welding generator PSG-500. Investigations of structural-phase changes in weld metal and HAZ were carried out by means of optical microscopy (optical microscope Versamet-2 and Neophot-32), microhardness was measured using M-400 gage of Leco company at 0.98N loading. Fractographic investigations were carried out by scanning electron microscopy (scanning electron microscope SEM-515 of PHILIPS company, Netherlands) on fractured specimens of welded joints, made as a result of impact bend tests. An analysis of crack resistance of the welded joints was carried out under different conditions of test temperatures. It was based on experimental data, received by a quantitative fractography method. It is shown that metal of a welded joint produced by hybrid laser-arc welding at Vw = 72m/h rate has mainly failure of ductile nature after external loading. This indicates sufficient level of crack resistance and further working capacity under operation conditions.

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