Modeling of weld pool phenomena in tungsten inert gas, CO2-laser and hybrid (TIG+CO2-laser) welding

Abstract

The efficiency of the welding process in terms of weld penetration and weld width is greatly determined by the heat, mass, and charge transfer phenomena in the weld pool. These phenomena, in turn, depend on the thermal and electromagnetic interaction of the heat source used with the metal being welded. The most adequate models of the welding processes should consider the interaction of the phenomena in the heat source, on the base metal surface and inside its volume by a self-consistent way. This paper is devoted to the development of a self-consistent model of weld pool dynamics in tungsten inert gas (TIG), laser and hybrid (laser + TIG) spot welding without a keyhole formation. The proposed model allows simulation of processes taking place in the weld pool and on its surface. The model takes into account free surface deformation, influence of plasma shear stress, thermocapillary Marangoni effect, and Lorentz forces on the weld pool, as well as of the processes in the arc plasma including laser-arc interaction. For this purpose, the model of the weld pool is combined with a model of arc plasma column where the interaction processes between Gaussian beam radiation emitted by a continuous-wave CO2 laser and the argon arc plasma are described. The equations of the model proposed are solved numerically by means of finite element method. The simulation results are compared with real welding experiments performed with steel S-235JR. A good accordance between simulation and experimental results is observed.

Thermocapillary approaches to the deliberate patterning of polymers

“…The resultant thermocapillary migration is observed as a ridge of material surrounding the "weld pool" of material melted during the weld, and has been studied mainly for its mitigation during welding. [91][92][93][94] In the late 1970s and early 1980s, similar surface rippling during the LSA of semiconductor thin films was observed by multiple researchers 95,96 and later attributed to thermocapillary forces by Cline et al 97 This effect and its suppression has been subsequently studied in laser 92,98,99 and electron-melted 100-102 hard matter. The first deliberate use of this effect to pattern structures was by Baumgart coworkers, who used the thermocapillary dewetting to generate structures for magnetic memory.…”

“…As a result, thermal gradients once again up to are regularly generated in the molten slag. The resultant thermocapillary migration is observed as a ridge of material surrounding the “weld pool” of material melted during the weld, and has been studied mainly for its mitigation during welding . In the late 1970s and early 1980s, similar surface rippling during the LSA of semiconductor thin films was observed by multiple researchers and later attributed to thermocapillary forces by Cline et al This effect and its suppression has been subsequently studied in laser and electron‐melted hard matter.…”

Non-Equimolar Cantor High Entropy Alloy Fabrication Using Metal Powder Cored Wire Arc Additive Manufacturing

“…The presence of the substrate metal with BCC lattice in deposited metal and vice versa are commonly known phenomena. This effect is explained by the 'Marangoni effect' [36][37][38] which describes mixing metal in the welding bath due to the convection flow of the molten metal under the arc pressure.…”

Laser Spot Welding a Three-Layered Panel in Different Spatial Positions

“…In welding industry spot welding is one of the most widespread methods of manufacturing thinsheet metal structures [19][20][21][22][23]. It is used to create products for construction purposes, railway cars, frame structures in rocket building, etc.…”