3D Finite Element Modelling of Weld Bead Penetration in Tungsten Inert Gas (TIG) Welding of AISI 1020 Low Carbon Steel Plate

Abstract

Weld quality is adversely influenced by bead penetration depth, as deeper penetration can improve the strength and load bearing capacity of weldments in service condition. Based on Design of Experiment (DOE), an experimental design matrix having thirteen (13) center points, six (6) axial points and eight (8) factorial points resulting in twenty (20) experimental runs was generated for TIG welding current, voltage, gas flow rate L/min and temperature. Maximum bead penetration of 8.44 mm was obtained from the FEM simulation with corresponding input variables of 190 A, 19 V, 18 L/min and 298.44 ^oC compared to maximum bead penetration of 7.942 mm obtained from the welding experimentation with corresponding input variables of 155 A, 22 V, 15.50 L/min and 278.46 ^oC.  To clearly understand the rate of heat distribution across the as-welded plate, FEM bead penetration profiles were developed using Solid Works (2017 version) thermal transient analysis which revealed that the higher the temperature distribution the wider the Heat Affected Zones (HAZs) which are indications of phase transformations and alterations in mechanical properties of the welded metal which may lead to induced residual stresses if the welding parameters particularly the amperage is not controlled adequately. In addition, there was proximity in the trend of bead penetration from the regression plot where the FEM model had a coefficient of determination (R²) of 0.9799 while R² of 0.9694 was obtained for the welding experimentation, indicating about 97.4% variance which in this context signifies that both bead penetration values can be adopted for real practical scenarios where deep weld bead penetrations are required.

Keywords

• TIG welding,Bead penetration,Temperature,Heat distribution

References

1. Razak, N. A., Shing, S. N. (2014). Investigation of effects of MIG welding on corrosion behaviour of AISI 1010 carbon steel. Journal of Mechanical Engineering and Sciences 7: 1168–78, Doi: 10.15282/jmes.7.2014.16.0114.
2. Nuraini, A. A., Zainal, A. S., Ariff, M. Hanim, A. (2014). The effects of Welding Parameters on Butt Joints Using Robotic Gas Metal Arc Welding. Journal of Mechanical Engineering and Sciences, 6: 988-994.
3. Singh, A. K., Dey, V., Rai, R. N. (2017). A Study to Enhance the Depth of Penetration in Grade P91 Steel Plate Using Alumina as Flux in FBTIG Welding. Arab Journal of Science and Engineering, 42: 4959-4970.
4. Memduh, K., Yukler, A., Bilici, M., Catalgol, Z. (2015). Effects Of Welding Current And Arc Voltage On Fcaw Weld Bead Geometry. International Journal of Research in Engineering and Technology, 4(9): 23-28.
5. Ikpe, A. E., Owunna, I., Ememobong, I. (2017). Effects of Arc Voltage and Welding Current on the Arc Length of Tungsten Inert Gas Welding (TIG). International Journal of Engineering Technologies-IJET, 3(4): 213-221.
6. Mohd, S., Mohd, P., Pratibha, K. (2013). Effect of MIG Welding Input Process Parameters on Weld Bead Geometry on HSLA Steel. International Journal of Engineering Science and Technology, Vol. 5(1): 200-212.
7. Bodude, M. A., Momohjimoh, I. (2015). Studies on Effects of Welding Parameters on the Mechanical Properties of Welded Low-Carbon Steel. Journal of Minerals and Materials Characterization and Engineering, 3: 142-153.
8. Sushant S. P. (2015). Theoretical and experimental study of MIG/MAG welding technique. International Journal of Engineering Trends and Technology (IJETT), 24(3): 142-144.

9. Abbasi, K., Alam, S., Khan, M. I. (2012). An Experimental Study on the Effect of MIG Welding parameters on the Weld-Bead Shape Characteristics. Engineering Science and Technology: An International Journal (ESTIJ), 2(4): 599- 602.
10. Satyaduttsinh P. C., Jayesh V., Tushar, M. (2014). A Review on Optimization of MIG Welding Parameters using Taguchi’s DOE Method. International Journal of Engineering and Management Research, 4(1): 16-21.
11. Yadav, P. K., Abbas, M., Patel, S. (2014). Analysis of Heat Affected Zone of Mild Steel Specimen Developed due to MIG Welding. International Journal of Mechanical Engineering and Robotic Research, 3(3): 399-404.
12. Tewari, S. P., Gupta, A., Prakash, J. (2010). Effect of Welding Parameters on the Weldability of Material, International Journal of Engineering Science and Technology, 2(4): 512-516.
13. Ghazvinloo, H. R., Honarbakhsh-Raouf, A., Shadfar, N. (2010). Effect of arc voltage, welding current and welding speed on fatigue life, impact energy and bead penetration ofAA6061 joints produced by robotic MIG welding. Indian Journal of Science and Technology, 3(2): 156-162.
14. Sudhakaran, R., Vel-Murugan, V., Sivasakthivel, P. S. (2012). Effect of Process Parameters on Depth of Penetration in Gas Tungsten Arc Welded (GTAW) 202 Grade Stainless Steel Plates Using Response Surface Methodology. The Journal of Engineering Research, 9(1): 64-79.
15. Cho, J. H., Na, S. J. (2009). Three-dimensional analysis of molten pool in GMA-laser hybrid welding. Welding Journal, 88: 35-43.
16. Piekarska, W., Kubiak, M. (2011). Three-dimensional model for numerical analysis of thermal phenomena in laser–arc hybrid welding process. International Journal of Heat and Mass Transfer, 54: 4966-4974.
17. Sura, N., Mittal, V. (2015). Experimental Study on Effects of Process Parameters on HAZ of Plain Carbon Steel Using GMAW. International Journal of Latest Research in Science and Technology, 4(2): 167-170.
18. www.kobelco.co.jp/english/welding/events/files/2015_KOBELCO_Defect.pdf, 2017.
19. Kamble, A. G., Rao, R. V. (2013). Experimental Investigation on the Effects of Process Parameters of GMAW and Transient Thermal Analysis of AlSl321 Steel. Advances in Manufacturing, 1(4): 362-377.