Phase filed simulation of dendritic growth of copper films irradiated by ultrashort laser pulses

A phase field model (PFM) is combined with a two-dimensional two-temperature model (TTM) to simulate the evolution of dendritic growth during re-solidification of ultrafast laser-material interaction. The dynamic solidification conditions at different locations of the melting pool obtained from TTM are fed into the quantitative PFM based on the macro-micro coupled method. A series of simulations are executed to investigate the influence of laser parameters, such as laser influence and pulse duration, on melting pool characteristics and local dendrite morphology. Besides, dendrite structures calculated at different areas of the melting pool were discussed based on local solidification conditions, and the simulated dendrite arm spacing (DAS) for various cooling rates was made comparison with previously published experimental data. The simulated results reveal that the maximum temperature gradient has significant influence on the local dendritic competitive growth, while the laser parameters effect the local microstructure distinctly due to the changes of solidification conditions. This work demonstrates the potential application of PFM to predict the microstructure morphology presented in ultrashort laser-material interaction and other industrially relevant conditions with complex solidification conditions. (C) 2018 Elsevier B.V. All rights reserved.