Arc welding in a rectangular path using DFLUX subroutine Abaqus

Project Overview

In this example, the arc welding process in a rectangular path is simulated using the DFLUX subroutine in Abaqus.

A volumetric heat flux is used to simulate the welding process. The Goldak's double-ellipsoid heat source model is used to define the volumetric heat flux around the welding pool.

The DFLUX subroutine is used to define the Goldak's double-ellipsoid heat source and the resulting nonuniform heat flux.

Rectangular Welding Path

One of the main features of this example is the rectangular welding path.

The welding torch moves successively through the following segments:

Therefore, the welding torch follows a rectangular path during the simulation. The movement of the heat source along this path is defined using the DFLUX subroutine.

Goldak's Double-Ellipsoid Heat Source

The Goldak's double-ellipsoid heat source model is adopted to calculate the volumetric heat flux distribution around the welding pool.

The equations of the Goldak heat source model are defined as a function of position and time, together with a number of heat source parameters.

The constants a, b, Cf, and Cr are heat source parameters that define the size and shape of the ellipses. These parameters are obtained from experimental analysis.

Welding Parameters

The welding parameters used in this simulation are:

• Welding voltage: 22 V
• Welding current: 110 A
• Welding efficiency: 0.8
• Welding speed: 10 mm/s

These parameters are used to define the heat input associated with the welding process.

Welding and Cooling Process

The analysis is performed in two steps.

In the first step, the welding process is simulated for a duration of 32 seconds. During this step, the moving volumetric heat flux is applied using the DFLUX subroutine.

In the second step, the welding heat source is removed and the cooling process is simulated for a duration of 120 seconds.

Thermal-Mechanical Analysis

Two Coupled Temperature-Displacement steps are defined for the simulation.

This analysis considers the thermal and mechanical response of the plate during the welding and subsequent cooling process.

Material Properties

The material of the plate is SUS304 stainless steel.

The following material properties are defined as temperature-dependent properties:

• Density
• Thermal conductivity
• Specific heat
• Thermal expansion
• Elastic properties
• Plastic properties

What You Will Learn

• How to simulate arc welding in Abaqus.
• How to use the DFLUX subroutine for arc welding.
• How to define a volumetric heat flux.
• How to implement Goldak's double-ellipsoid heat source.
• How to define a nonuniform heat flux using DFLUX.
• How to simulate welding along a rectangular path.
• How to define the AB, BC, CD, DE and EA welding segments.
• How to control the movement of the welding torch using DFLUX.
• How to define welding voltage of 22 V.
• How to define welding current of 110 A.
• How to define welding efficiency of 0.8.
• How to define a welding speed of 10 mm/s.
• How to define Goldak heat source parameters.
• How to define the parameters a, b, Cf and Cr.
• How to perform a 32-second welding step.
• How to perform a 120-second cooling step.
• How to perform a Coupled Temperature-Displacement analysis.
• How to define temperature-dependent material properties.
• How to implement a Fortran DFLUX subroutine in Abaqus.

Key Features

• Arc welding simulation in Abaqus.
• Rectangular welding path.
• DFLUX Fortran subroutine.
• Volumetric heat flux.
• Goldak's double-ellipsoid heat source.
• Nonuniform heat flux distribution.
• Welding path: AB → BC → CD → DE → EA.
• Welding voltage: 22 V.
• Welding current: 110 A.
• Welding efficiency: 0.8.
• Welding speed: 10 mm/s.
• 32-second welding stage.
• 120-second cooling stage.
• Two Coupled Temperature-Displacement steps.
• Temperature-dependent material properties.
• SUS304 stainless steel.
• Goldak heat source parameters a, b, Cf and Cr.
• Research article included.