Experimental and Numerical Investigation of Residual Stress and Distortion Control during Welding of AISI-316L Plates

Abstract:

Welding residual stress and subsequent distortions are a common problem during fabrication. Several techniques for controlling residual stress and distortion during welding, amongst which transient thermal tensioning is one of the more promising methods. Thermal tensioning can be achieved by two side heaters moving along with the weld heat source. The concept of transient thermal tensioning induces a redistribution of the stress field in the welded plate by altering the thermal field. In this paper, the results are presented on the mitigation of out-of-plane deformation during gas tungsten arc butt welding of 2 mm thick AISI-316L stainless steel. Acetylene-air burners are applied as side heaters. The thermal tensioning process induces a number of additional process parameters including the intensity, the size and the location of the heaters. A thermo-mechanical (TM) finite element model is used to cope with the complexity of the process. The model provides a better understanding of the development of the stress field, both in conventional and transient thermal tensioned welds and of the mechanisms which mitigate distortion. The model is validated by temperature, stress and distortion measurements. It appears that the redistribution of stresses and the introduction of tensile stresses by side heating is the main mechanism responsible for the reduction of distortion.

• Periodical: Materials Science Forum (Volumes 706-709)
• Pages: 2950-2955
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.706-709.2950
• Online since: January 2012
• Authors: A.M.A. Pazooki, M.J.M. Hermans, I.M. Richardson
• Keywords: Numerical Modeling, Transient Thermal Tensioning, Welding, Welding Distortion, Welding Residual Stress (WRS)

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DOI: 10.1201/9780203402818