Validation of transient thermal analysis of 4 mm butt-welded joints using thermocouples and infrared camera

Abstract

In this study, finite element transient thermal analysis was conducted to simulate thermal history of S700 steel butt-welded joints with thickness of 4 mm welded using gas metal arc welding process. The validation of thermal analysis was investigated by comparing its results with laboratory measurements of thermal history using thermocouples and infrared camera. The accuracy of infrared camera and emissivity values were validated using thermocouples. Goldak’s double ellipsoid heat source model was used in the thermal analysis to simulate heat input caused by the welding process. The cooling process was modelled through convection and radiation heat loss. Both the heat source and the heat loss models were incorporated in Abaqus software using user’s subroutine DFLUX and SFILM. The effect of modelling parameters is discussed and a validation of the thermal analysis using laboratory measurements is reached. The results also show that infrared camera may be calibrated to show acceptably accurate results to be used when validating the thermal analysis.