颗粒对Al-4.5 wt% Cu合金定向凝固汇聚生长的元胞自动机模拟研究  

Cellular Automata Simulation Study of Particles on the Convergent Growth of Al-4.5 wt%Cu Alloys for Directional Solidification

作　　者：傅瑜峰 葛鸿浩 蒋波 任凤丽 倪益华[1] FU Yufeng;GE Honghao;JIANG Bo;REN Fengli;NI Yihua(College of Optical,Mechanical and Electrical Engineering,Zhejiang A&F University,Hangzhou 311300,China;College of Mechanical Engineering,Zhejiang University of Technology,Hangzhou 310014,China;Hangzhou Steam Turbine Power Group Co.,Ltd.,Hangzhou 310022,China)

机构地区：[1]浙江农林大学光机电工程学院,杭州311300 [2]浙江工业大学机械工程学院,杭州310014 [3]杭州汽轮铸锻股份有限公司,杭州310022

出　　处：《有色金属工程》2024年第8期39-46,共8页Nonferrous Metals Engineering

基　　金：国家自然科学基金青年项目(52304415);浙江省自然科学基金(LQ22E040002)。

摘　　要：定向凝固是制备单晶的重要技术之一,被广泛应用于航空航天、能源、电子、医疗器械等领域。但是在定向凝固过程中难免会出现杂晶、夹杂等缺陷,因此研究颗粒对枝晶竞争生长机制的影响对制备高品质单晶试样具有重要意义。基于欧拉多相流模型与元胞自动机方法,通过构建Al-4.5 wt%Cu合金枝晶生长模型,比较不同取向枝晶在相同条件下获得的枝晶前沿溶质分布和枝晶长度差异来验证模型的可靠性,然后开展了定向凝固双晶粒凝固组织演化和颗粒对枝晶生长影响的研究。模拟结果表明,无颗粒影响的汇聚竞争生长中非择优取向枝晶压制择优取向枝晶生长,再现了反常淘汰现象。但是通过将颗粒引入合金定向凝固汇聚生长的晶界附近后,颗粒的存在干扰了非择优生长取向枝晶生长,亦可提高择优取向枝晶生长稳定性,实现了对反常淘汰现象的控制。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.

关 键 词：元胞自动机 定向凝固 汇聚生长 模拟研究 

分 类 号：TG111.4[金属学及工艺—物理冶金]