论文标题
谷物不兼容决定了无定形晶界肤色的局部结构
Grain incompatibility determines the local structure of amorphous grain boundary complexions
论文作者
论文摘要
无定形的晶界肤色缺乏远距离的晶体顺序，但并非没有特征，因为已经通过其厚度报道了结构短距离顺序中的不同梯度。在这项工作中，我们检验了以下假设：短距离顺序的分布是通过使用Cu-ZR双晶和随机多晶的原子模拟来确定晶体的。 Voronoi Polyhedra的结构类似于完美面部的立方体作为高结构秩序的特征，仅在无定形 - 晶体过渡区域才能找到。发现特定的无定形晶体过渡区域内有序结构基序的密度不是直接由接触谷物的晶粒的方向和对称性确定，而是通过两种约束晶粒之间的不兼容。发现有序的多面体密度与谷物不相容性成反比，这意味着狭窄晶体之间的较大不相容性导致无定形 - 晶状体过渡区域的顺序较小。必须考虑必须考虑整个晶粒膜颗粒系统以明确理解局部结构的发现，表明无定形肤色不仅是在晶界处发生成核的独立相的集合。相反，无定形的晶界肤色是找到局部平衡构型的单个实体。
Amorphous grain boundary complexions lack long-range crystalline order but are not featureless, as distinct gradients in structural short-range order have been reported through their thickness. In this work, we test the hypothesis that the distribution of short-range order is determined by the confining crystals using atomistic simulations of both Cu-Zr bicrystals and a random polycrystal. Voronoi polyhedra with structures similar to that of perfect face-centered cubic serve as signatures of high structural order and are only found at the amorphous-crystalline transition regions. The density of the ordered structural motifs within a specific amorphous-crystalline transition region is found to not be directly determined by the orientation and symmetry of the grain which touches it, but rather by the incompatibility between the two confining grains. Ordered polyhedra density is found to be inversely related to grain incompatibility, meaning that large incompatibilities between the confining crystals lead to less order in the amorphous-crystalline transition region. The finding that the entire grain-film-grain system must be considered to understand local structure unequivocally demonstrates that amorphous complexions are not simply a collection of independent phases which happen to nucleate at a grain boundary. Rather, an amorphous grain boundary complexion is a single entity that finds a local equilibrium configuration.
