Cellular Automata Simulation Study of Particles on the Convergent Growth of Al-4.5 wt％ Cu Alloys for Directional Solidification
Directional solidification is one of the important techniques for the preparation of single crystals,which is widely used in aerospace,energy,electronics,medical devices and other fields.However,defects such as stray crystals and inclusions inevitably occur during directional solidification,so it is important to study the effect of particles on the competitive growth mechanism of dendrites for the preparation of high-quality single-crystal specimens.In this paper,based on the Eulerian multiphase flow model and the metacellular automata method,the reliability of the model is verified by constructing a dendrite growth model for Al-4.5 wt％Cu alloys,and comparing the differences in the solute distribution along the front of the dendrite and the length of the dendrite obtained from dendrites with different orientations under the same conditions,and then carrying out a study on the evolution of the solidification organisation of the two grains during the directional solidification and the effect of the particles on the growth of the dendrites.The simulation results show that non-optimally oriented dendrites suppress the growth of optimally oriented dendrites in the convergent competitive growth without the influence of particles,reproducing the anomalous elimination phenomenon.However,by introducing particles into the alloy near the grain boundaries of directional solidification convergent growth,the presence of particles interferes with the growth of non-optimally oriented dendrites and improves the stability of optimally oriented dendrites,thus controlling the anomalous elimination phenomenon.
万方数据
