Laser cladding process inherently includes multi-scale, highly non-linear, and non-equilibrium transport phenomena due to non-uniform and rapid heat flow caused by the laser and the material interaction. Therefore, there is a growing demand to develop systematic modeling and simulation approaches for the multi-scale problem. To address this issue, a process model of solidification microstructure evolution has been studied by utilizing a phase-field method. The phase-field method has become a widely used computational tool for the modeling of solidification microstructure evolution with the advantage of avoiding tracking the interface explicitly and satisfying interfacial boundary conditions. In present work, the numerical solutions of a phase-field model have been analyzed. The linking of macro-scale process and solidification microstructure evolution was examined by considering the relationship of macro- and micro-parameters. The effects of laser power on clad height and surface roughness have also been studied. The predicted results for pure metal dendrite growth were compared with the microsolvability theory and a good agreement was found. Different solidification morphologies of different locations in the melt pool are also investigated. It was found that it is not the mass transfer but the heat transfer in the melt pool that dominates the solidification process.
Coupled Analysis of Microstructure Evolution with Creep Deformation in Nickel-based Superalloys by the Phase- field Method
