Stress analysis on welded specimen with multiple methods

Abstract

Effects of the thermal stress due to welding on the mechanical property of the welded work are analyzed with multiple methods. Strain gauges and an acoustic microscope are used to measure the residual stress, and electronic speckle pattern interferometry (ESPI) is used to analyze the response of the welded wok to external force. A tensile load is applied to butt-welded, thin-plate steel specimens, and the resultant strain field is analyzed with the ESPI. Comparison is made with the case of a non-welded specimen of the same material and dimensions. The analyses indicate that the residual stress due to welding makes the normal strain due to the external tensile load asymmetric. The asymmetry enhances shear and rotational modes of deformation, generating stress concentration at a point away from the weld where the residual stress is substantially negligible.