PDF(Sci-hub)
Abstract：
Recently we have developed a new energetic model based on the determination of the energies on each site of random solid solutions after relaxation as a function of both the local composition and the nominal concentration. It allows to determine the main thermodynamics driving forces of disordered alloys. Here, we extend the effective site energy model to ordered alloys and illustrate the results for the AucPd1-csystem. As a first step, we show the ability of this energetic model to reproduce the hierarchy of ordered phases. Then, we derive general mean-field analytic formulae for ordered systems and get the phase diagram. We determine the relative role of the cohesive effect, the chemical effect and the size effect and find that the chemical effect differs significantly between the disordered state and the ordered state. Finally, we link the energy formation of antisite to the permutation enthalpy and give the driving forces for the formation of antisite.
摘要：
最近，我们开发了一种新的能量模型，该模型基于确定弛豫后随机固溶体每个位置上的能量作为局部成分和标称浓度的函数。它允许确定无序合金的主要热力学驱动力。这里,我们将有效位点能量模型扩展到有序合金，并说明了AucPd1-c系统的结果。作为第一步,我们展示了这种能量模型再现有序相层次的能力。然后，我们推导了有序系统的一般平均场解析公式，并得到了相图。我们确定了凝聚效应的相对作用，化学效应和尺寸效应，发现无序状态和有序状态之间的化学效应存在显着差异。最后,我们将反位点的能量形成与排列焓联系起来，并给出反位点形成的驱动力。
