Topological Characteristics of Two-Dimensional Grain Growth-Simulation and Analysis
Topological Characteristics of Two-Dimensional Grain Growth-Simulation and Analysis
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DOI：
10.1007/s11661-009-0139-0
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发表时间：
2010-03
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影响因子：
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通讯作者：
A. Sprague;B. Patterson;Suresh Grandhi
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文献类型：
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作者：
A. Sprague;B. Patterson;Suresh Grandhi
一个二维（2-D）晶粒生长模拟，使用曲率驱动的顶点模型应用到最初的蒙特卡罗（MC）生成的微结构，已开发的拓扑特性的过程中，包括不同的拓扑事件的速率和这些事件的影响，不断演变的晶粒结构的分析。研究结果包括一个恒定的比例消失的晶粒的数量分数的面积分数扫过的晶界的4/3;边界清扫由于晶粒消失（~ 2%），边界切换事件（~ 8%），和简单的边界运动（~ 90%）的恒定分数;和一个恒定的比例为1.34边界切换事件每晶粒消失。开发了一个亲和力项来描述不同边缘类的颗粒相对于随机行为相互接触或参与不同拓扑事件的趋势。最高和最低的边类，3和12，分别表现出最高的亲和力相互接触，16次随机发生，但亲合力约为0与自己的接触。中间边缘类显示出~1的亲和力，随机接触，与其他类或与自己。少边晶粒在接触消失的三角形或在边缘切换事件中获得边缘时显示出~0的亲和力，但在切换事件中失去边缘时具有接近6的高亲和力。多边缘颗粒表现出相反的趋势和中间边缘类表现出随机或较少的趋势参与任何拓扑事件。统计结果表明，单个晶粒的生长速率完全由边缘类控制，基本上没有直接的影响，从晶粒尺寸。的晶粒面积和边缘类分布的演变进行了监测整个过渡从瞬态到稳态晶粒生长，达到稳定状态后，损失约1/3的初始晶粒。边缘类和晶粒面积分布的变异系数（CV）的稳态值分别为~0.2和0.7。
A two-dimensional (2-D) grain growth simulation, using a curvature-driven vertex model applied to an initially Monte Carlo (MC)–generated microstructure, has been developed for analysis of the topological characteristics of the process, including the rates of different topological events and the effect of these event frequencies on the evolving grain structure. Findings include a constant ratio of the number fraction of disappearing grains to the area fraction swept by the grain boundary of 4/3; constant fractions of boundary sweeping due to grain disappearance (~2 pct), boundary-switching events (~8 pct), and simple boundary motion (~90 pct); and a constant ratio of 1.34 boundary-switching events per grain disappearance. An affinity term was developed to describe the tendency of grains of different edge classes to contact each other or to be involved in different topological events, relative to random behavior. The highest and lowest edge classes, 3 and 12, respectively, exhibited the highest affinity for mutual contact, a 16 times random occurrence, but an affinity of ~0 for contact with themselves. Intermediate edge classes showed an affinity of ~1, random contact, with other classes or with themselves. Few-edged grains showed ~0 affinity for contacting a disappearing trigon or gaining an edge in an edge-switching event, but had a high affinity, approaching 6, for losing an edge in a switching event. Many-edged grains showed the opposite trends and intermediate edge classes showed a random or less tendency for participation in any topological event. It was shown statistically that the growth rate of individual grains is controlled solely by the edge class, with essentially no direct effect from the grain size. The evolution of the grain area and edge class distributions were monitored throughout the transition from transient to steady-state grain growth, with a steady state achieved after loss of approximately 1/3 of the initial grains. The steady-state values of the coefficients of variation (CVs) of the edge class and grain area distributions were ~0.2 and 0.7, respectively.