Importance of outliers: A three-dimensional study of coarsening in α -phase iron
Importance of outliers: A three-dimensional study of coarsening in
α
-phase iron
复制标题
异常值的重要性：α 粗化的三维研究
DOI：
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发表时间：
2019
影响因子：
3.4
通讯作者：
Robert M. Suter
中科院分区：
文献类型：
--
作者：
Yu;S. Maddali;David B. Menasche;A. Bhattacharya;Gregory S. Rohrer;Robert M. Suter
用高能X射线衍射显微镜研究了α相铁样品的三维晶粒粗化行为。完全在样品内部的4971个颗粒在初始状态下被分段，3905个颗粒在退火后保持不变。一个匹配程序被用来跟踪这两个状态之间的3299个颗粒，而其余的要么被邻居消费，要么跟踪算法无法将它们关联起来。在单次退火热处理过程中，平均晶粒体积增加了13%。每种状态下的统计分析都产生了颗粒大小和最近邻数分布的细微变化。将拓扑特征与状态之间的体积变化相关联，平均行为被认为符合曲率驱动粗化的各向同性模型，但每个拓扑类中体积变化的分散度与平均行为的总体趋势相当。因此，在各向同性假设下，这里使用的拓扑特征并不能预测单个颗粒的行为。对轶事案例的研究可以理解一些离群值，但另一些似乎与各向同性理论背道而驰。
Grain coarsening behavior in an α-phase iron sample is studied in three dimensions using high energy x-ray diffraction microscopy. 4971 grains that are entirely inside the sample are segmented in the initial state and 3905 remain after annealing. A matching procedure was used to track 3299 grains between the two states while the remainder were either consumed by neighbors or the tracking algorithm failed to correlate them. During the single annealing treatment, the average grain volume increased by 13%. Statistical analysis in each state yields subtle changes in the grain size and nearest neighbor number distributions. Correlating topological features with volume changes between states, the average behavior is seen to be consistent with an isotropic model of curvature driven coarsening, but the dispersion of volume changes in each topological class is comparable to the overall trend in the average behaviors. Thus, the topological characterizations used here are not predictive of the behavior of individual grains under the isotropic assumption. Examination of anecdotal cases allows understanding of some outliers but others appear counter to an isotropic theory.