Phase-Field Simulation of Grain Boundary Evolution In Microstructures Containing Second-Phase Particles with Heterogeneous Thermal Properties
Phase-Field Simulation of Grain Boundary Evolution In Microstructures Containing Second-Phase Particles with Heterogeneous Thermal Properties
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DOI：
10.1038/s41598-019-54883-8
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发表时间：
2019-12
影响因子：
4.6
通讯作者：
T. Flint;Y. Sun;Q. Xiong;M. Smith;J. Francis
中科院分区：
文献类型：
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作者：
T. Flint;Y. Sun;Q. Xiong;M. Smith;J. Francis
了解复杂的热场和金属组织之间的相互作用，在细观尺度是至关重要的预测在热机械加工过程中的微观组织演变。晶粒的竞争生长是冶金学和固体物理学中最基本的现象之一。第二相粒子的存在，作为钉扎网站的边界，大大改变了系统的粗化行为，特别是当考虑到这些粒子具有不同的热性能的主相。在这项工作中，多相场模型，结合热梯度和曲率驱动力，被用来预测晶粒生长aTi6Al4V合金系统与第二相颗粒夹杂物的氧化物和碳化物沉淀物的代表。多相场框架完全耦合到热方程。热梯度驱动力的结合使得能够预测颗粒周围的晶界的详细行为。它示出，具有较低的热导率的颗粒的夹杂物上的各种系统的晶粒的粗化行为有显着的影响，由于热屏蔽和边界和钉扎颗粒之间的热梯度驱动力的产生的综合效应。
Understanding the interaction between complex thermal fields and metallic structures at the meso-scale is crucial for the prediction of microstructural evolution during thermomechanical processing. The competitive growth of crystal grains, driven by thermodynamic forces at the grain boundaries, is one of the most fundamental phenomena in metallurgy and solid state physics. The presence of second phase particles, which act as pinning sites for boundaries, drastically alters the coarsening behaviour of the system; particularly when considering that these particles have different thermal properties to the primary phase. In this work a multi-phase field model, incorporating thermal gradient and curvature driving forces, is used to predict grain growth in aTi6Al4Valloy system with second phase particle inclusions representative of oxide and carbide precipitates. The multi-phase field framework is fully coupled to the heat equation. The incorporation of the thermal gradient driving force enables the detailed behaviour of the grain boundaries around the particles to be predicted. It is shown that the inclusion of particles with a lower thermal conductivity has a significant influence on the coarsening behaviour of various systems of grains, due to the combined effects of thermal shielding and the generation of thermal gradient driving forces between the boundaries and pinning particles.