An analytical solution to predict the transient temperature distribution in fillet arc welds

This paper presents an analytical solution for predicting the transient temperature distribution in fillet arc welds. The analytical solution is obtained by solving a transient, three-dimensional heat conduction equation with convection boundary conditions on the surfaces of an infinite plate with finite thickness and mapping an infinite plate onto the fillet weld geometry with an energy equation. The electric arc heat input on the fillet weld and on the infinite plate is assumed to have a traveling bivariate Gaussian distribution. To check the validity of the solution, gas tungsten arc (GTA) and flux cored arc (FCA) welding experiments were performed under various conditions. The actual isotherms of the weldment cross sections at various distances from the arc start point are compared with those of the simulation result. As the result shows satisfactory accuracy, this analytical solution can be used to predict the transient temperature distribution in fillet welds of finite thickness under a moving bivariate Gaussian distributed heat source. The simplicity and short calculation time of the analytical solution provide rationale to use the analytical solution for modeling welding control systems or for optimizing welding process parameters.