Numerical Simulation of Heat Transfer and Fluid Flow in Co-axial Laser Cladding of Ti6Al4V Alloys

In this article, a 2D FEM model is built to simulate the heat transfer and fluid flow in the laser cladding process of the Ti6Al4V alloy. Physical phenomena such as melt pool generation, mass addition due to powder flow, Marangoni convection, and re-solidification of the melt pool have been incorporated in the developed model. The governing equations pertaining to mass, momentum, and energy were solved in a Lagrangian moving frame to predict temperature and velocity field along with geometrical dimensions of the deposited clad. The temperature and temperature gradients were calculated at “14” located points in three different directions, to scrutinize the thermal behavior of the melt pool. Further, the influence of driving forces such as Marangoni force and thermal buoyancy force was analyzed. The prediction of microstructure evolution was based on the estimation of the temperature gradient, cooling rate, and solidification rate in the fusion zone.