Material World Network: Theoretical, Computational and Experimental Studies of 3D Microstructural Evolution in Ultra-high Volume Fraction Coarsening System

提出了一项为期三年的研究项目，对超高体积分数（V V0.9）固液混合物的三维相粗化进行理论、计算和实验研究。本项目的主要目标是：(1)利用时间分辨x射线微层析成像技术测量两相体系的三维微观结构演变，从而同时揭示粗化的全局平均动力学和内部界面的局部迁移；(2)进行了超高电压下三维相粗化的大规模相场模拟，预测了相变的全局和局部特征；(3)建立了超高电压下相粗化理论，填补了适用于低电压下的Lifshitz/ Slyozov/Wagner理论与晶粒生长理论（V V1.0）之间的空白；(4)通过与仿真和实验结果的定量比较，对理论进行检验和改进。该项目是美国科学家和德国科学家之间的合作，前者将从事理论和计算方面的研究，后者将通过断层扫描进行样品制备和表征。

A three-year research project is proposed to conduct theoretical, computational and experimental studies of three-dimensional phase coarsening in ultra-high-volume-fraction (V V 0.9 ) solid-liquid mixtures. The primary goals of this project are (1) to measure the three-dimensional microstructural evolution of two-phase systems in situ using timeresolved x-ray microtomography, thus revealing simultaneously the globally averaged kinetics of coarsening and the local migration of internal interfaces; (2) to conduct largescale phase-field simulations of 3-D phase coarsening at ultra-high V V , obtaining predictions regarding the global and local characteristics of the transformation; (3) to develop a new theory for phase-coarsening at ultra-high V V , thus filling the gap between the Lifshitz/ Slyozov/Wagner theory, which is valid at low V V , and theories for grain growth (V V 1.0 ); and (4) to test and improve the theory by comparing its predictions quantitatively to the results of simulation and experiment. The project is a collaborative effort between scientists in the USA, who will pursue the theoretical and computational aspects, and Germany, where the sample preparation and characterization via tomography will be carried out.