Welding in the World

, Volume 53, Issue 9–10, pp R253–R263

# Experimental Studies and Mathematical Modelling of Penetration in TIG and A-TIG Stationary Arc Welding of Stainless Steel

• Konstantin A. Yushchenko
• Dmitry V. Kovalenko
• Igor V. Krivtsun
• Igor V. Kovalenko
• Aleksey B. Lesnoy
Peer-Reviewed Section

## Abstract

Experimental investigations of the kinetics of penetration of stainless steel in TIG and A-TIG welding, and theoretical analysis of thermal, electromagnetic and hydrodynamic processes occurring in the weld pool metal were conducted. The stationary arc welding process was chosen as the focus of investigation, in order to study physical-metallurgical peculiarities of metal penetration in TIG and A-TIG welding. This makes it possible to describe processes occurring in the weld pool within the framework of axisymmetric approximation. The conjugate model of heat exchange in the base metal and hydrodynamics of the weld pool, with the melt affected by the electromagnetic (Lorentz force), buoyancy (Archimedean force) and thermal-capillary (Marangoni effect) forces, was formulated. Comparative analysis of the impact of the electric characteristics of the arc (current, voltage, anode spot diameter) and different force factors causing motion of liquid metal on hydrodynamics of the weld pool and shape of penetration of stainless steel in TIG and A-TIG welding was carried out by the method of mathematical modelling. The relationship between the deformation of the free surface of the molten metal (due to changes in its density depending on the temperature) and energy characteristics of the arc was analysed. It is shown that in contraction of the anode region of the arc (with decrease in diameter of the anode spot, which is characteristic of A-TIG welding), the magnetic-hydrodynamic processes become the dominating factor, determining the penetration depth and formation of the weld as a whole.

## IIW-Thesaurus keywords

A TIG welding Arc welding Gas shielded arc welding GTA welding Mathematical models Penetration Practical investigations Reference lists Stainless steels Steels

## References

1. [1]
Yushchenko K.A., Savitskiy M.M., Kovalenko D.V., Lupan A.F.: A-TIG welding of carbon-manganese and stainless steel, In Proceedings of Conference “Welding technology Paton Institute” (Abington, Oct., 1993), Abington Publishers, 1993, pp. 254–262.Google Scholar
2. [2]
Lucas W., Howse D.S., Savitsky M.M., Kovalenko I.V.: A-TIG flux for increasing the performance and productivity of welding processes, IIW Doc. XII-1448–96, 1996.Google Scholar
3. [3]
Savitsky M.M., Kushnirenko V.N., Olejnik O.I.: Features A-TIG welding of steels, The Paton Welding Journal, 1999, Pilot issue, pp. 20–26.Google Scholar
4. [4]
Lowke J., Tanaka M., Ushio M.: Mechanisms giving increased weld-depth to a flux, Journal of Physics D: Applied Physics, 2005, vol. 38, pp. 3438–3445.
5. [5]
Yushchenko, K.A., Kovalenko, D.V., Kovalenko, I.V.: Comparative analysis of A-TIG and TIG welding of stainless steel, IIW Doc. SG-212-1088–05, 2005.Google Scholar
6. [6]
Paton B.E., Yushchenko K.A., Kovalenko D.V., Krivtsun I.V., Demchenko V.F., Kovalenko I.V., Lesnoi A.B.: Factors of increasing penetrating capacity of A-TIG welding of stainless steel, IIW Doc. XII-1911–06, 2006.Google Scholar
7. [7]
David S.A., DebRoy T., Vitek J.M.: Phenomenological modelling of fusion welding processes, MRS Bulletin, 1994, vol. 14, no. 1, p. 29.Google Scholar
8. [8]
Lowke J., Tanaka M., Ushio M.: Insulation effects of flux layer in producing greater weld depth, IIW Doc. SG-212-1053-04/XII-1800–04, 2004.Google Scholar
9. [9]
Sato T., Ochiai T., Fujii H., Lu S., Nogi K.: Effect of shielding gas on penetration shape in double shielded GTA welding, IIW Doc. XII-1892–06, 2006.Google Scholar
10. [10]
Tanaka M., Lowke J.: Predictions of weld pool profiles using plasma physics, Journal of Physics D: Applied Physics, 2007, vol. 40, R1–R23.
11. [11]
Paton B.E., Yushchenko K.A., Kovalenko D.V., Krivtsun I.V., Demchenko V.F., Kovalenko I.V., Lesnoj A.B.: Role of quasi-keyhole and Marangoni convection in formation of deep penetration in A-TIG welding of stainless steel (Phenomenological model of A-TIG welding of stainless steel. In: Proceedings of Joint 16th Int. Conf. on Computer Technology in Welding and Manufacturing and 3rd Int. Conf. on Mathematical Modelling and Information Technologies in Welding and Related Processes (Kiev, Ukraine, June, 2006), Kiev: PWI, pp. 258–263.Google Scholar
12. [12]
Paton B.E., Yushchenko K.A., Kovalenko D.V., Krivtsun I.V., Demchenko V.F., Kovalenko I.V.: Formation of quasi keyhole is a cause of deep penetration in A-TIG welding of stainless steel, IIW Doc. SG-212-1085–05, 2005.Google Scholar
13. [13]
Yushchenko K.A., Kovalenko D.V., Kovalenko I.V.: Investigation of peculiarities of A-TIG welding of stainless steels, Doc. IIW SG-212-1047–03, 2003.Google Scholar
14. [14]
Shoek P.A.: Investigation of energy balance at the anode of high-current arcs burning in argon atmosphere, Current Problems of Heat Transfer, M.-L.: Energiya, 1966, pp. 110–139.Google Scholar
15. [15]
Füssel U., Schnick M., Munoz J.E.F., Zschetzsche J., Siewert E.: Experimentelle Moglichkeiten der WSG-Lichtbogenanalyse (Experimental possibilities of TSG arc investigations), Schweissen und Schneiden, 2007, vol. 59, no. 7–8, pp. 396–403 (in German).Google Scholar
16. [16]
Krivtsun I.V., Demchenko V.F., Lesnoy A.B.: Model of evaporation-condensation processes in welding and material treatment. In: Proc. of Joint 16th Int. Conf. on Computer Technology in Welding and Manufacturing and 3rd Int. Conf. On Mathematical Modelling and Information Technologies in Welding and Related Processes (Kiev, Ukraine, June, 2006), Kiev: PWI, 2006, pp. 184–187.Google Scholar
17. [17]
Lyashko I. I., Demchenko V.F., Vakulenko S.A.: Modification of the method for splitting the equations of dynamics of viscous incompressible liquid on the Langrangian-Euler nets, Doklady AN USSR, series A, 1981, pp. 43–47.Google Scholar
18. [18]
Demchenko V.F., Lesnoi A.B.: Langrangian-Euler method for numerical solution of multi-dimensional problems of convective diffusion. Doklady AN USSR, 2000, 11, pp. 71–75.Google Scholar
19. [19]
Lancaster J.F., Mills K.C.: Recommendations for the avoidance of variable penetration in gas tungsten arc welding, Doc. IIW-1194-92 (ex-doc. SG-212-796–91), Abington publishing, 1994.Google Scholar
20. [20]
Fujii H, Suglyama H., Lu S.P., Yamashina K., Tanaka M., Nogi K.: Effect of Minor Elements on Penetration Depth in GTA Welding, Journal of JWRI, 2001, vol. 61, no. 4, pp. 97–102.Google Scholar

© International Institute of Welding 2009

## Authors and Affiliations

• Konstantin A. Yushchenko
• 1
• Dmitry V. Kovalenko
• 1
• Igor V. Krivtsun
• 1