Phase‐field–lattice Boltzmann simulation of dendrite growth under natural convection in multicomponent superalloy solidification

Authors:
Publisher website
Google Scholar
Abstract
The thermosolutal convection can alter segregation pattern, change dendrite morphology and even cause freckles formation in alloy solidification. In this work, the multiphase‐field model was coupled with lattice Boltzmann method to simulate the dendrite growth under melt convection in superalloy solidification. In the isothermal solidification simulations, zero and normal gravitational accelerations were applied to investigate the effects of gravity on the dendrite morphology and the magnitude of melt flow. The solute distribution of each alloy component along with the dendrite tip velocity during solidification was obtained, and the natural convection has been confirmed to affect the microsegregation pattern and the dendrite growth velocity. In the directional solidification simulations, two typical temperature gradients were applied, and the dendrite morphology and fluid velocity in the mushy zone during solidification were analyzed. It is found that the freckles will form when the average fluid velocity in the mushy zone exceeds the withdraw velocity.
Funding Information
  • National Key Research and Development Program of China (2017YFB0701503)
  • National Natural Science Foundation of China (51374137)
  • National Key Research and Development Program of China (2017YFB0701503)
  • National Science and Technology Major Project (2017ZX04014001)
  • National Natural Science Foundation of China (51374137)

This publication has 29 references indexed in Scilit: