Elastic-Plastic Modeling of the Residual Stresses Caused by Laser Beam Welding in Aerospace Structures

Authors

1 M. Sc., Mech. Eng. Dept., Urmia Univ., Urmia, Iran

2 Assoc. Prof., Mech. Eng. Dept., Urmia Univ., Urmia, Iran

Abstract

An appropriate joining technology is the laser beam welding process, because of its low localized energy input leading to low distortion, high strength of the joint and high processing speeds. The growing of aircraft industry in reducing the weight of aerospace structure has led the introduction of laser beam welding into the fabrication of aerospace structure with stiffeners, instead of riveted joints. In the present paper an analytical model for calculation of the residual stresses induced by laser welding is proposed and numerically validated.
The aim of this work is to study the transverse residual stress distribution of plates made of an aluminum alloy 6061-T6, which is used for fabrication of fuselage panels. The results show that, if the maximum stress amount induced in the workpiece does not exceed the material yield stress, no plastic penetration will occur and there will be no residual stress. It was found that high stresses are developing close to the plate surface while these stresses decrease rapidly to almost zero values at the lower surface. An ideal elastic-plastic material curve was assumed. Good accordance is found between the calculated and numerical results.

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References

[1] Labeas G, Diamantakos I (2013) Laser beam welding residual stresses of cracked T-joints. Theor Appl Fract Mec 63-64: 69-76.
[2] Zain-ul-abdein M, Daniel N, Jullien J, Deloison D (2010) Experimental investigation and finite element simulation of laser beam welding induced residual stresses and distortions in thin sheets of AA 6056-T4. Mater Sci Eng A 527: 3025-3039.
[3] Schubert E, Klassen M, Zerner I, Walz C, Sepold G (2001) Light-weight structures produced by laser beam joining for future applications in automobile and aerospace industry. J Mater Process Tech 115: 2-8.
[4] Yang Z, Tao W, Li L, Chen Y, Li F, Zhang Y (2012) Double-sided laser beam welded T-joints for aluminum aircraft fuselage panels: process, microstructure, and mechanical properties. Mater Design 33: 652–658.
[5] Moraitis G, Labeas G (2008) Residual stress and distortion calculation of laser beam welding for aluminum lap joints. J Mater Process Tech 198: 260-269.
[6] Ranatowski E, Ciechacki K (2010) Mathematical modelling of laser welding in shipbuilding. Sci J 24(96): 80–87.
[7] Ranatowski E (2010) Problems of welding in shipbuilding. Part I: Theoretical basis of modelling and an analytical assessment of heat sources models. Pol Marit Res 1(64): 75-79.
[8] Lee H, Wu  Jia (2009) Correlation between corrosion resistance properties and thermal cycles experienced by gas tungsten arc welding and laser beam welding Alloy 690 butt weldments. Corros Sci 51:733-743.
[9] Yang L, Xiao Z (1995). Elastic-plastic  modelling of  the  residual  stress  caused  by  welding. J Mater Process Tech 48: 589-601.
[10] Zimmerman J, Wlosinski W, Lindemann Z (2009) Thermo-mechanical and diffusion modelling in the process of ceramic–metal friction welding. J Mater Process Tech 209: 644-653.
[11] Kong F, Ma J, Kovacevic R (2011) Numerical and experimental study of thermally induced residual stress in the hybrid laser–GMA welding process. J Mater Process Tech 211: 1102-1111.
Journal of Solid and Fluid Mechanics
Volume 5, Issue 2 - Serial Number 2
July and August 2015
Pages 153-162

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