Modeling Heat and Mass Transfer and Fluid Flow in Three-Dimensional Gas Metal Arc Welding

Manufacturing ◽  
2002 ◽  
Author(s):  
Y. Wang ◽  
H. L. Tsai ◽  
S. P. Marin ◽  
P. C. Wang
Keyword(s):  
Weld Pool ◽  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Three Dimensional ◽  
Marangoni Effect ◽  
Surface Tension Force ◽  
Droplet Impingement ◽  
Metal Arc Welding ◽  
Welding Direction ◽  
First Time

This paper extends a mathematical model and numerical techniques previously developed for simulating stationary 2-D gas metal arc welding (GMAW), to moving 3-D GMAW. The filler droplets carrying mass, momentum, thermal energy, and species periodically impinge onto the weld pool, while moving at a certain speed in the welding direction. The complicated transport phenomena in the weld pool are caused by the combined effect of droplet impingement, gravity, electromagnetic force, plasma arc force, and surface tension force (Marangoni effect). The weld pool shape and the distributions of temperature, species, and velocity in the weld pool are calculated as functions of time. For the first time, the phenomena of “open and close-up” for a crater and the formation of ripples at the surface of a solidified weld bead are predicted by mathematical modeling. Under the welding conditions used in the present study, detailed mechanisms leading to the formation of ripples are discussed.

scholarly journals Weld Pool Dynamics and the Formation of Ripples in 3D Gas Metal Arc Welding

2007 ◽  
Author(s):  
J. Hu ◽  
H. Guo ◽  
H. L. Tsai
Keyword(s):  
Weld Pool ◽  
Arc Welding ◽  
Present Model ◽  
Gas Metal Arc Welding ◽  
Marangoni Effect ◽  
Surface Tension Force ◽  
Plasma Arc ◽  
Droplet Impingement ◽  
Metal Arc Welding ◽  
First Time

This article studies the transient weld pool dynamics under the periodical impingement of filler droplets that carry mass, momentum, thermal energy, and species in a moving 3D gas metal arc welding. The complicated transport phenomena in the weld pool are caused by the combined effect of droplet impingement, gravity, electromagnetic force, plasma arc force, and surface tension force (Marangoni effect). The weld pool shape and the distributions of temperature, velocity, and species in the weld pool are calculated as a function of time. The phenomena of “open and close-up” for a crater in the weld pool and the corresponding weld pool dynamics are analyzed. The commonly observed ripples at the surface of a solidified weld bead are, for the first time, predicted by the present model. Detailed mechanisms leading to the formation of ripples are discussed.

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.

Modeling of Metal Transfer in Short Circuiting Arc Welding

2004 ◽  
Author(s):  
Guo Xu ◽  
William W. Schultz ◽  
Elijah Kannatey-Asibu ◽  
S. Jack Hu ◽  
Pei-Chung Wang
Keyword(s):  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Marangoni Effect ◽  
Welding Current ◽  
Metal Transfer ◽  
Vof Model ◽  
Metal Arc Welding ◽  
Method Effects ◽  
Velocity Pressure ◽  
First Time

The short-circuiting metal transfer during gas metal arc welding (GMAW) is simulated by a numerical model. To the best of our knowledge, for the first time the energy equation and the Marangoni convection are considered in analyzing the short-circuiting time. A front-tracking free surface method is applied to explicitly track the bridge profile. To benchmark this method, effects of the density and viscosity ratios between different phases are investigated by simulating a drop driven by surface tension. The temporal profile of the drop is compared to that computed by a Volume of Fluid (VOF) model, and very good agreement is found. The model is then applied to simulate GMAW short-circuiting transfer. The velocity, pressure, temperature and electromagnetic fields are calculated. Effects of welding current and Marangoni shear stress on short-circuiting time are examined. It is shown that the Marangoni effect plays an important role in GMAW short-circuiting transfer.

Three-Dimensional Modeling of Gas Metal Arc Welding of Aluminum Alloys

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
H. Guo ◽  
J. Hu ◽  
H. L. Tsai
Keyword(s):  
Weld Pool ◽  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Three Dimensional ◽  
Welding Process ◽  
Weld Bead ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
Metal Arc Welding ◽  
Arc Welding Process

A three-dimensional mathematical model and numerical techniques were developed for simulating a moving gas metal arc welding process. The model is used to calculate the transient distributions of temperature and velocity in the weld pool and the dynamic shape of the weld pool for aluminum alloy 6005-T4. Corresponding experiments were conducted and in good agreement with modeling predictions. The existence of a commonly observed cold-weld at the beginning of the weld, ripples at the surface of the weld bead, and crater at the end of the weld were all predicted. The measured microhardness around the weld bead was consistent with the predicted peak temperature and other metallurgical characterizations in the heat-affected zone.

scholarly journals Investigation on the Dynamic Behavior of Weld Pool and Weld Microstructure during DP-GMAW for Austenitic Stainless Steel

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 754
Author(s):  
Tao Chen ◽  
Songbai Xue ◽  
Peng Zhang ◽  
Bo Wang ◽  
Peizhuo Zhai ◽  
...  
Keyword(s):  
Weld Metal ◽  
Dynamic Behavior ◽  
Weld Pool ◽  
Heat Input ◽  
Arc Welding ◽  
Gas Metal Arc Welding ◽  
Oscillation Amplitude ◽  
Droplet Impingement ◽  
Metal Arc Welding ◽  
Arc Pressure

The influence of heat and droplet transfer into weld pool dynamic behavior and weld metal microstructure in double-pulsed gas metal arc welding (DP-GMAW) was investigated by the self-designed high-speed welding photography system. The heat input, the arc pressure, the droplet momentum and impingement pressure were measured and calculated. It was found that the arc pressure is far less than the droplet impingement pressure. The heat input and droplet impingement pressure per unit time acting on weld pool were proportional to the current pulse frequency, which fluctuated with thermal pulse. The size and oscillation amplitude of the weld pool had noticeable periodic changes synchronized with the process of heat input and droplet impingement. Compared to the microstructure of pulsed gas metal arc welding (P-GMAW) weld metal, that of DP-GMAW weld metal was significantly refined. High oscillation amplitude assisted the enhancement of weld pool convection, which leads to more constitutional supercooling. The heat input and shear force during the peak of thermal pulse causing dendrite fragmentation which provided sufficient crystal nucleus for the growth of equiaxed grains and the possibility of grain refinement. The effects of current parameters on welding behavior and weld metal grain size are investigated for further understanding of DP-GMAW.

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.

Sign in / Sign up

Export Citation Format

Share Document