Abstract:

For better understanding of the residual stress fields associated with Tungsten Inert Gas (TIG) welding, thermal analysis was carried out using Solid Works 2017 version and ESI Visual-Environment to compute the transient temperature profile due to welding thermal loading and resulting stress field in three categories namely; von-mises stress, axial stress and thermal stress. A range of welding temperatures including 1746oC , 1912oC , 2100oC , 2410oC and 2800oC were experimentally applied in the joining process of AISI 1020 low carbon steel plate of 10 mm thickness and a strain gauge was used to measure the thermal stresses induced in the steel plate which the average was recorded as 38,200MPa. The experimental parameters and conditions were applied in finite element simulation of the same plate dimension, and average von-mises stress of 37,508 MPa , average axial stress of 30,732 MPa and average thermal stress of 20,101 MPa was obtained. However, it was observed that the higher the welding temperature, the higher the stresses induced in the welding material. Hence, temperature for TIG welding process should be regulated at its optimum to avoid fatigue acceleration, stress propagation, early crack nucleation and possible fracture on the welded component which may limit the longevity and performance of such component in its service condition.

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