Measurement of Residual Stresses of DH32 Steel Plates in Different Welding Joints by Using Conventional Strain Gauges and FEA Methods

Abstract

Residual stresses are those stresses that remain in an object (in particular, in a welded component) even in the absence of external loading or thermal gradients. In some cases, residual stresses result in significant plastic deformation, leading to warping and distortion of an object. This paper investigates the prediction of residual stresses developed in shielded metal arc welding of high thickness DH32 (ASTM A131) steel plates through Finite Element Simulation and experiments. To evaluate the residual stresses in weldment, conventional strain gauges are used. These stresses are developed on the Butt joint and T joint. The geometry of the T joint and butt-welded Low Carbon Steel (ASTM A131) plates was modeled and the residual stresses were simulated using ANSYS V19.2. Sequentially coupled transient thermal-mechanical, three-dimensional finite element models were developed and the Element Birth and Death Technique was used in simulation to evaluate the stresses in simulation. The conventional strain gauges are placed in different weld zones and the obtained results from these gauges are different as per the FE results. These results show that the residual stresses obtained by prediction from the finite element method are in fair agreement with the experimental results. Based on this, it can be concluded that how far we can use the strain gauges used in the measurement of residual stresses. and also the Finite Element Model can be used to replicate and determine the expected residual stresses that would be generated before an actual welding process is carried out.