Simulation of dendritic deformation induced by convection in alloy solidification

Abstract

Abstract Dendritic deformation induced by convection of thermal fluid is one of the factors leading to dendrite fragmentation and plays a crucial role in grain structure of alloy, which lacks in-depth understanding. In this paper, we simulate the flow-induced mechanical deformation of dendrites during the solidification of Al-4.5wt.%Cu alloy by combining the cellular automaton-finite volume method (CA-FVM) for the dendrite growth and the finite element method (FEM) for handling the dendritic deformation with the complex boundary conditions given by CA-FVM results. It shows that the dendritic deformation strongly depends on the flow velocities of melt and dendritic morphology. The dendrites can undergo visible bending above the critical flow velocities for dendrite yield (ranging from 0.023 m/s to 0.126 m/s as the inlet velocity increases) and the von Mises stress increases as the flow is enhanced during the growth process.