Development of Numerical Models of the Weld Pool and the Heat Source in Gas Metal Arc Welding

2017 ◽  
Vol 86 (1) ◽  
pp. 32-37
Author(s):  
Yosuke OGINO
Keyword(s):  
Heat Source ◽  
Weld Pool ◽  
Arc Welding ◽  
Numerical Models ◽  
Gas Metal Arc Welding ◽  
Metal Arc Welding

Modeling of Three-Dimensional Gas Metal Arc Welding With Groove

2007 ◽  
Author(s):  
J. Hu ◽  
H. L. Tsai
Keyword(s):  
Weld Pool ◽  
Arc Welding ◽  
Filler Metal ◽  
Gas Metal Arc Welding ◽  
Three Dimensional ◽  
Plasma Arc ◽  
Droplet Impingement ◽  
Sulfur Species ◽  
Metal Arc Welding ◽  
Arc Pressure

This article analyzes the dynamic process of groove filling and the resulting weld pool fluid flow in gas metal arc welding of thick metals with V-groove. Filler droplets carrying mass, momentum, thermal energy, and sulfur species are periodically impinged onto the workpiece. The complex transport phenomena in the weld pool, caused by the combined effect of droplet impingement, gravity, electromagnetic force, surface tension, and plasma arc pressure, were investigated to determine the transient weld pool shape and distributions of velocity, temperature, and sulfur species in the weld pool. It was found that the groove provides a channel which can smooth the flow in the weld pool, leading to poor mixing between the filler metal and the base metal, as compared to the case without a groove.

Tandem laser-gas metal arc welding joining of 20 mm thick super duplex stainless steel: An experimental and numerical study

2020 ◽  
Vol 234 (5) ◽  
pp. 697-710
Author(s):  
A Mathieu ◽  
I Tkachenko ◽  
JM Jouvard ◽  
I Tomashchuk
Keyword(s):  
Numerical Simulation ◽  
Heat Source ◽  
Laser Beam ◽  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Image Correlation ◽  
Angular Distortion ◽  
Metal Arc Welding ◽  
Welded Structure ◽  
Welding Processes

The present work covers the topic of strains and stresses prediction in case of welded steel structures. Steel sheets of 20 mm thickness made in UR™2507Cu are welded using a laser and gas metal arc welding processes combination. The focused laser beam leads the arc in a Y-shape chamfer geometry. Both sources are 20 mm apart from each other in order to avoid any synergic effect with each other. In order to predict residual strain, a 3D unsteady numerical simulation has been developed in COMSOL finite element software. A volume heat source has been identified based on the temperature measurements made by 10 K-type thermocouples, implanted inside the workpiece. The 50 mm deep holes are drilled in the workpiece using dye-sinking Electrical Discharge Machining (EDM) machine. Before the implantation in the hole, each thermocouple is surrounded by Inconel sheathing. Hot junctions of the thermocouples are positioned in a way to feel two advancing molten pools. The equivalent heat source is composed of three sources. First one is a Goldak source that represents the molten pool induced by gas metal arc welding. The second one is a cylinder with an elliptic cross-section that represents the focused laser beam penetrating into the workpiece. The third one is a surface Gaussian source that represents energy radiated by arc and blocked by workpiece surface. Concerning mechanical simulation, an elasto-plastic behavior with isotropic hardening is implemented. A weak coupling is established between equations governing heat transfer and mechanics thanks to the temperature dependent coefficient of linear expansion. This numerical simulation made with some simplifying assumptions predicts an angular distortion and a longitudinal shrinkage of the welded structure. The numerical results are consistent with the displacements measured by digital image correlation method.

scholarly journals An adaptive approach to compensate seam tracking error in robotic welding process by a moving fixture

2018 ◽  
Vol 15 (6) ◽  
pp. 172988141881620
Author(s):  
Reza Ebrahimpour ◽  
Rasul Fesharakifard ◽  
Seyed Mehdi Rezaei
Keyword(s):  
Weld Pool ◽  
Arc Welding ◽  
Sliding Mode ◽  
Gas Metal Arc Welding ◽  
Tracking Error ◽  
Welding Process ◽  
Seam Tracking ◽  
Ball Screw ◽  
Robotic Welding ◽  
Metal Arc Welding

Welding is one of the most common method of connecting parts. Welding methods and processes are very diverse. Welding can be of fusion or solid state types. Arc welding, which is classified as fusion method, is the most widespread method of welding, and it involves many processes. In gas metal arc welding or metal inert gas–metal active gas, the protection of the molten weld pool is carried out by a shielding gas and the filler metal is in the form of wire which is automatically fed to the molten weld pool. As a semi-metallic arc process, the gas metal arc welding is a very good process for robotic welding. In this article, to conduct the metal active gas welding torch, an auxiliary ball screw servomechanism is proposed to move under a welder robot to track the welded seam. This servomechanism acts as a moving fixture and operates separately from the robot. At last, a decentralized control method based on adaptive sliding mode is designed and implemented on the fixture to provide the desired motion. Experimental results demonstrate an appropriate accuracy of seam tracking and error compensation by the proposed method.

scholarly journals Multi-objective calibration of the double-ellipsoid heat source model for GMAW process simulation

2021 ◽  
pp. 181-181
Author(s):  
Miso Bjelic ◽  
Branko Radicevic ◽  
Karel Kovanda ◽  
Ladislav Kolařík ◽  
Aleksandra Petrovic
Keyword(s):  
Numerical Model ◽  
Heat Source ◽  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Calibration Procedure ◽  
Source Model ◽  
Objective Functions ◽  
Heat Source Model ◽  
Metal Arc Welding ◽  
Input Parameters

The scope of application of simulation models in welding is limited by the accuracy of their output results. This paper presents a calibration procedure for a three-dimensional quasi-stationary model of heat transfer for gas metal arc welding. The double-ellipsoid heat source used in this model has five input parameters whose value cannot be specified accurately. To estimate these values, we employed a multi-objective calibration procedure with two objective functions using the paretosearch optimization algorithm. Objective functions represented the error between simulated and experimentally observed values of penetration depth and weld bead width during gas metal arc welding of P355GH steel plates. All input parameters were assumed to be a power function of line energy. To reduce computational time, we replaced the numerical model with a response surface methodology metamodel based on an optimal set of simulation results from the numerical model. The results of the simulations based on calculated values of input parameters for the heat source model showed excellent matching with the experimental results.

Sign in / Sign up

Export Citation Format

Share Document