Three-dimensional phase-field simulation of microstructural evolution in three-phase materials with different interfacial energies and different diffusivities
Three-dimensional phase-field simulation of microstructural evolution in three-phase materials with different interfacial energies and different diffusivities
复制标题
不同界面能和不同扩散系数三相材料微观结构演化的三维相场模拟
DOI：
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发表时间：
2017
影响因子：
4.5
通讯作者：
N. Moelans
中科院分区：
文献类型：
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作者：
Hamed Ravash;J. Vleugels;N. Moelans
三相材料，如共晶合金的粗化行为，是一个很有技术价值的问题。本文以三维三元三相多晶材料为研究对象，研究了体扩散和相排列对粗化动力学的影响。
扩散迁移率被定义为在三个阶段是不同的。通过改变相界能和晶界能，得到了不同相排列的显微组织，其中不同类型的晶粒有交替或聚集的趋势。在所有情况下，达到一个政权的平均晶粒尺寸遵循幂增长规律与增长指数$$n=3$$n=3，表明体扩散控制粗化。相排列、相界能的大小和不同相的扩散迁移率明显地影响整体生长速率和单个相的生长速率。在所有情况下，具有最低扩散迁移率的相显示出最高的生长速率和平均更大数量的晶粒面。虽然晶粒面的平均数量在具有恒定晶界能的系统中在时间上变得恒定，但晶粒面的平均数量在整个模拟时间期间当晶界能是取向差依赖的时继续增加。
AbstractThe coarsening behavior of three-phase materials, such as eutectic alloys, is of high technological interest. In this study, 3D ternary three-phase polycrystalline materials were modeled to study the effect of bulk diffusion and phase arrangement on the coarsening kinetics.
The diffusion mobilities were defined to be different in the three phases. By varying the phase boundary and grain boundary energies, microstructures with different phase arrangements were obtained, in which the different types of grains had a tendency to alternate or cluster. In all cases, a regime was reached where the average grain size follows a power growth law with growth exponent $$n=3$$n=3, indicating bulk diffusion-controlled coarsening. The overall growth rate and that of the individual phases were clearly affected by the phase arrangement, the magnitude of the phase boundary energy and the diffusion mobilities of the different phases. In all cases, the phase with the lowest diffusion mobility showed the highest growth rate and on average a larger number of grain faces. While the average number of grain faces became constant in time in systems with constant grain boundary energy, the average number of grain faces continued to increase during the whole simulation time when the grain boundary energy was misorientation dependent.