EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Grain microstructures formed during solidification processes have a large influence on the mechanical properties of cast metals and alloys. The Cellular Automaton – Finite Element (CAFE) method is a method for simulating grain microstructures coupled with thermal evolution at a scale of approximately one liter. In the classical CAFE method, only the envelop of dendritic grains is modeled on a cellular grid, using an analytical law to determine the envelop growth velocity at the scale of automaton cells. This analytical law is however not relevant to describe dendritic kinetics under non-stationary state. The Parabolic Thick Needle (PTN) method, representing dendritic branches as a network of needles, is a numerical method to model dendritic growth at a scale between the microscopic scale of the Phase-Field (PF) method and the mesoscopic scale of the Cellular Automaton (CA) method. This model determines the growth velocity of dendrite branches from the concentration flux in the vicinity of dendrite tips. In order to improve the precision of the classical CAFE method, we couple the CA method with the PTN method. The PTN method is implemented based on Finite Element method and adaptive anisotropic meshing technic. Growth of dendritic grains under both stationary and non-stationary condition is simulated using the Cellular Automaton – Parabolic Thick Needle (CAPTN) method. Our simulation results are compared with benchmarks of published results of the PF method.