A canonical stability–elasticity relationship verified for one million face-centred-cubic structures
A canonical stability–elasticity relationship verified for one million face-centred-cubic structures
复制标题
针对一百万个面心立方结构验证了规范的稳定性-弹性关系
作者：
Maisel;Höfler;Müller
任何稳定或亚稳定的相对应于一个潜在的非常复杂的能量景观的局部最小值。但是，无论晶体有多复杂，这种能量景观在其最小值附近都是抛物线形的。粗略地说，这个能量阱相对于某个参考能级的深度决定了系统的热力学稳定性，而抛物线在其最小值附近的陡度决定了系统的弹性性质。虽然改变合金元素及其在给定材料中的浓度以增强某些性能可以追溯到青铜时代，但在固定化学计量下系统地寻找亚稳原子构型中的理想性能是材料设计中的一个非常新的工具。在这里，我们证明，使用第一性原理研究的四个二元合金系统，面心立方金属间化合物的弹性性能服从一定的规则。基于对面心立方配置空间的一个巨大子集的计算，我们得出了两个结论。首先，刚度和热的形成是负相关的几乎恒定的斯皮尔曼相关性的所有浓度。第二，在固定浓度下，亚稳组态的平均刚度随它们到基态线（零开尔文下合金的相图）的距离线性衰减。我们希望我们的方法将有助于简化从广阔的配置空间中寻求具有最佳性能的新材料。
Any thermodynamically stable or metastable phase corresponds to a local minimum of a potentially very complicated energy landscape. But however complex the crystal might be, this energy landscape is of parabolic shape near its minima. Roughly speaking, the depth of this energy well with respect to some reference level determines the thermodynamic stability of the system, and the steepness of the parabola near its minimum determines the system’s elastic properties. Although changing alloying elements and their concentrations in a given material to enhance certain properties dates back to the Bronze Age,, the systematic search for desirable properties in metastable atomic configurations at a fixed stoichiometry is a very recent tool in materials design. Here we demonstrate, using first-principles studies of four binary alloy systems, that the elastic properties of face-centred-cubic intermetallic compounds obey certain rules. We reach two conclusions based on calculations on a huge subset of the face-centred-cubic configuration space. First, the stiffness and the heat of formation are negatively correlated with a nearly constant Spearman correlation for all concentrations. Second, the averaged stiffness of metastable configurations at a fixed concentration decays linearly with their distance to the ground-state line (the phase diagram of an alloy at zero Kelvin). We hope that our methods will help to simplify the quest for new materials with optimal properties from the vast configuration space available.
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希腊、伊特鲁里亚和罗马文明使用的铜合金的成分： 2. 古风、古典和希腊化时期的希腊人
影响因子：
2.8
作者：
P. Craddock
通讯作者：
P. Craddock
大自然缺失的结构在哪里？
影响因子：
41.2
作者：
G. Hart
通讯作者：
G. Hart
影响因子：
2.8
作者：
CRADDOCK, PT
通讯作者：
CRADDOCK, PT
DOI：
10.1088/0965-0393/17/5/055003
发表时间：
2009-07-01
影响因子：
1.8
作者：
Lerch, D.;Wieckhorst, O.;Mueller, S.
通讯作者：
Mueller, S.