0
Research Papers

Coupled Field Analysis of a Gas Tungsten Arc Welded Butt Joint—Part II: Parametric Study

[+] Author and Article Information
D. Sen

Department of Mechanical Engineering,
Virginia Tech,
Blacksburg, VA 24061
e-mail: sen@vt.edu

M. A. Pierson, K. S. Ball

Department of Mechanical Engineering,
Virginia Tech,
Blacksburg, VA 24061

1Corresponding author.

Manuscript received December 10, 2012; final manuscript received April 2, 2013; published online December 13, 2013. Assoc. Editor: Lili Zheng.

J. Thermal Sci. Eng. Appl 6(2), 021009 (Dec 13, 2013) (11 pages) Paper No: TSEA-12-1222; doi: 10.1115/1.4024704 History: Received December 10, 2012; Revised April 02, 2013

The process of welding has a direct influence on the integrity of the structural components and their mechanical response during service. Welding is an inherently multiphysics problem, encompassing a large array of physical phenomena—fluid flow in the weld pool, heat flow in the structure, microstructural evolution/phase transformations, thermal stress development, and distortion of the welded structure. The mathematical model to simulate the coupled fields of the welding process has been outlined in Part I of the present study. In Part I, the developed model have been validated with experimental results and the depth/width (D/W) predictions agree well. Part II documents the effects of welding parameters (welding current/speed, electrode gap, and electrode angle) on the weld D/W ratio, for both low (≤40 ppm) and high (≥150 ppm) surface active agent (oxygen) content. The parametric characterization of the weld D/W ratio is validated with published experimental data. They agree well. Results show that increasing the oxygen content beyond 150 ppm does not increase the weld D/W ratio. At high oxygen content of 150 ppm and under current variation, the weld D/W ratio increases and remains constant beyond 160 A. However, when the welding speed is varied, the weld D/W ratio decreases with increasing speed. Similarly, increasing the electrode gap under high oxygen content decreases the weld D/W ratio. The weld D/W ratio shows weak variation with electrode tip angle. The results from the present simulations have also been used to predict the modes of weld solidification. With increase in welding speed, finer dendritic microstructures are expected to be formed near the weld centerline. The variation of weld D/W with heat input per unit length of weld is also presented elaborately. The workpiece deformation and stress distributions are also highlighted. The present study shows the pertinence of coupled welding process simulation to delineate the underlying physical processes and thereby better predict the behavior of welded structures.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Kou, S., 2002, Welding Metallurgy, 2nd ed., John Wiley & Sons, New York.
Sen, D., Pierson, M. A., and Ball, K. S., 2013, “Coupled Field Analysis of a Gas Tungsten Arc Welded Butt Joint—Part I: Improved Modeling,” ASME J. Therm. Sci. Eng. Appl., 5(1), p. 011010. [CrossRef]
Sluzalec, A., 1990, “Thermal Effects in Friction Welding,” Int. J. Mech. Sci., 32, pp. 467–478. [CrossRef]
Khandkar, M. Z. H., and Jamil, K., 2003, “Predicting Residual Thermal Stresses in Friction Stir Welding,” ASME IMECE, Washington, DC, Nov. 15–21, Vol. 374, pp. 355–360.
Canas, J., Picon, R., Paris, F., Blazquez, A., and Marin, J. C., 1996, “A Simplified Numerical Analysis of Residual Stresses in Aluminum Welded Plates,” Comput. Struct., 58(1), pp. 59–69. [CrossRef]
Oddy, A. S., McDill, J. M., and Goldak, J. A., 1990, “Consistent Strain Fields in 3D Finite Element Analysis of Welds,” ASME J. Pressure Vessel Technol., 112(3), pp. 309–311. [CrossRef]
Yuan, F., and Sun, H., 1991, “Transient Temperature Fields and Residual Stress Fields of Metallic Materials Under Welding,” Appl. Math. Mech., 12, pp. 595–599. [CrossRef]
Murakawa, H., Luo, Y., and Ueda, Y., 1998, “Theoretical Prediction of Welding Deformation at Groove in Narrow Gap Welding,” ASM Proceedings of the International Conference: Trends in Welding Research, Pine Mountain, GA, pp. 993–998.
Chidiac, S. E., and Mirza, F. A., 1993, “Thermal Stress Analysis Due to Welding Processes by the Finite Element Method,” Comput. Struct., 46, pp. 407–412. [CrossRef]
Kong, F., and Kovacevic, R., 2010, “3D Finite Element Modeling of the Thermally Induced Residual Stress in the Hybrid Laser/Arc Welding of Lap Joint,” J. Mater. Process. Technol., 210, pp. 941–950. [CrossRef]
Oreper, G. M., Eagar, T. W., and Szekely, J., 1983, “Convection in Arc Weld Pools,” Weld. J., 62(11), pp. 307–312.
Kou, S., and Wang, Y. H., 1986, “Weld Pool Convection and Its Effect,” Weld. J., 65(3), pp. 63s–70s.
Heiple, C. R., and Roper, J. R., 1982, “Mechanism for Minor Element Effect on GTA Fusion Zone Geometry,” Weld. J., 61, pp. 97s–102s.
Heiple, C. R., and Roper, J. R., 1982, “Effects of Minor Elements of GTAW Fusion Zone Shape,” Trends in Welding Research in the United States, ASM, Materials Park, OH, pp. 489–520.
Heiple, C. R., Roper, J. R., Stagner, R. T., and Aden, R. J., 1983, “Surface Active Element Effects on the Shape of GTA, Laser, and Electron Beam Welds,” Weld. J., 62, pp. 72s–77s.
Sheng, I. C., and Chen, Y., 1992, “Modeling Welding by Surface Heating,” ASME J. Eng. Mater. Technol., 114, pp. 439–449. [CrossRef]
Chen, Y., and Sheng, I. C., 1993, “On the Solid-fluid Transition Zone in Welding Analysis,” ASME J. Eng. Mater. Technol., 115, pp. 17–23. [CrossRef]
Leblond, J. B., and Devaux, J. C., 1984, “A Kinetic Model for Anisothermal Metallurgical Transformation in Steels Including Effect of Austenite Grain Size,” Acta Metall., 32, pp. 137–146. [CrossRef]
Leblond, J. B., Mottet, G., and Devaux, J. C., 1986, “A Theoretical and Numerical Approach to the Plastic Behavior of Steels During Phase Transformations: I: Derivation of General Equations,” J. Mech. Phys. Solids, 34, pp. 395–409. [CrossRef]
Oddy, A. S., Goldak, J. A., and McDill, J. M., 1990, “A General Transformation Plasticity Relation for 3D Finite Element Analysis of Welds,” Eur. J. Mech. A/Solids, 9, pp. 253–263.
Oddy, A. S., Goldak, J. A., and McDill, J. M., 1992, “Transformation Plasticity and Residual Stresses in Single-Pass Repair Welds,” ASME J. Pressure Vessel Technol., 114, pp. 33–38. [CrossRef]
Ronda, J., Murakawa, H., Oliver, G. J., and Ueda, Y., 1995, “Thermo-Mechano-Metallurgical Model of Welded Steel: II. Finite Element Formulation and Constitutive Equations,” Trans. JWRI, 14, pp. 1–21.
Kim, J. W., Im, S. W., and Kim, H. G., 2005, “Numerical Implementation of a Thermo-Elastic-Plastic Constitutive Equation in Consideration of Transformation Plasticity in Welding,” Int. J. Plast., 21, pp. 1383–1408. [CrossRef]
Deng, D., and Murakawa, H., 2006, “Prediction of Welding Residual Stress in Multi-Pass Butt-Welded Modified 9cr-1Mo Steel Pipe Considering Phase Transformation Effects,” Comput. Mater. Sci., 37, pp. 209–219. [CrossRef]
Lee, C. H., 2008, “Computational Modeling of the Residual Stress Evolution due to Solid-State Phase Transformation During Welding,” Modell. Simul. Mater. Sci. Eng., 16, pp. 1–16. [CrossRef]
Lindgren, L. E., 2001, “Finite Element Modeling and Simulation of Welding. Part 1: Increased Complexity,” J. Therm. Stresses, 24(2), pp. 141–192. [CrossRef]
Lindgren, L. E., 2001, “Finite Element Modeling and Simulation of Welding. Part 2: Improved Material Modeling,” J. Therm. Stresses, 24(3), pp. 195–231. [CrossRef]
Lindgren, L. E., 2007, Computational Welding Mechanics—Thermomechanical and Microstructural Simulations, 1st ed., Woodhead Publishing, Cambridge, UK.
Lu, S. P., Fujii, H., and Nogi, K., 2005, “Influence of Welding Parameters and Shielding Gas Composition on GTA Weld Shape,” ISIJ Int., 45, pp. 66–70. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Weld D/W ratio variation with surface active agent (oxygen) content

Grahic Jump Location
Fig. 2

Weld D/W ratio variation with welding current under (a) low (30 ppm) oxygen content and (b) high (150 ppm) oxygen content

Grahic Jump Location
Fig. 3

Weld D/W ratio variation with welding speed under (a) low (30 ppm) oxygen content and (b) high (150 ppm) oxygen content

Grahic Jump Location
Fig. 4

Weld D/W ratio variation with electrode gap (arc length) under (a) low (30 ppm) oxygen content and (b) high (150 ppm) oxygen content

Grahic Jump Location
Fig. 5

Weld D/W ratio variation with electrode tip angle

Grahic Jump Location
Fig. 6

Weld D/W ratio variation with heat input per unit weld length for cases (a) welding current changed to vary heat input and (b) welding speed changed to vary heat input

Grahic Jump Location
Fig. 7

Effect of temperature gradient G and growth rate R on the morphology and size of solidification microstructure

Grahic Jump Location
Fig. 8

Schematic plot for calculation of temperature gradients at the weld centerline and fusion line

Grahic Jump Location
Fig. 9

Variation of temperature gradient at weld centerline and fusion line against welding speed with 100 ppm of oxygen under 160 A current, and 1 mm arc length

Grahic Jump Location
Fig. 10

Variation of (a) G/R and (b) G*R at the weld pool centerline with different welding speeds

Grahic Jump Location
Fig. 11

Structural analysis boundary conditions definition

Grahic Jump Location
Fig. 12

x-direction deformation (in meters) of the workpiece. Welding away from fixed face AA′B′B.

Grahic Jump Location
Fig. 13

y-direction deformation (in meters) of the workpiece. Welding away from fixed face AA′B′B.

Grahic Jump Location
Fig. 14

z-direction deformation (in meters) of the workpiece. Welding away from fixed face AA′B′B.

Grahic Jump Location
Fig. 15

Total deformation (in meters) of the workpiece. Welding away from fixed face AA′B′B.

Grahic Jump Location
Fig. 16

x-direction deformation (in meters) of the workpiece. Welding toward the fixed face CC′D′D.

Grahic Jump Location
Fig. 17

y-direction deformation (in meters) of the workpiece. Welding toward the fixed face CC′D′D.

Grahic Jump Location
Fig. 18

z-direction deformation (in meters) of the workpiece. Welding toward the fixed face CC′D′D.

Grahic Jump Location
Fig. 19

Total deformation (in meters) of the workpiece. Welding toward the fixed face CC′D′D.

Grahic Jump Location
Fig. 20

Distribution of von-Mises stress when face AA′B′B is fixed and welding is done away from the fixed face

Grahic Jump Location
Fig. 21

Distribution of von-Mises stress when face CC′D′D is fixed and welding is done toward the fixed face

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In