Numerical Simulation of the Grains Growth on Titanium Alloy Electron Beam Welding Process

Abstract

In the paper, the grain growth of TC4-DT (Damage Tolerance) alloy joint during electron beam welding (EBW) process was simulated by using Cellular Automaton method. In order to consider the effects of the growth of neighborhood cellular on the center cells in the model, the solid fraction and solute distribution algorithms of classical CA model were improved. The growth of equiaxed grains and columnar crystals under uniform and nonuniform temperature fields was simulated successfully by applying the modified model, respectively. The temperature distribution near the fusion line of TC4-DT EBW joint was also calculated by using double ellipsoid heat source model. Then, coupling the CA model with the temperature field, the grain growth process of the cross-section of the welded zone was simulated. The simulation result fits well with experimental ones on the morphology and the size of the columnar crystals.