Liu Li, Paudel Ramesh, Liu Yong, Zhao Xiao-Liang, Zhu Jing-Chuan
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Nepal Academy of Science and Technology (NAST), Khumaltar, Lalitpur 44700, Nepal.
Materials (Basel). 2020 Sep 30;13(19):4353. doi: 10.3390/ma13194353.
The fundamental challenge for creating the crystal structure model used in a multi-principle element design is the ideal combination of atom components, structural stability, and deformation behavior. However, most of the multi-principle element alloys contain expensive metallic and rare earth elements, which could limit their applicability. Here, a novel design of low-cost AlCrTiFeNi multi-principle element alloy is presented to study the relationship of structure, deformation behavior, and micro-mechanism. This structured prediction of single-phase AlCrTiFeNi by the atomic-size difference, mixing enthalpy ΔHmix and valence electron concentration (VEC), indicate that we can choose the bcc-structured solid solution to design the AlCrTiFeNi multi-principle element alloy. Structural stability prediction by density functional theory calculations (DFT) of single phases has verified that the most advantageous atom occupancy position is (FeCrNi)(AlFeTi). The experimental results showed that the structure of AlCrTiFeNi multi-principle element alloy is bcc1 + bcc2 + L phases, which we propose as the fundamental reason for the high strength. Our findings provide a new route by which to design and obtain multi-principle element alloys with targeted properties based on the theoretical predictions, first-principles calculations, and experimental verification.
在多主元设计中创建晶体结构模型面临的根本挑战是原子组分、结构稳定性和变形行为的理想组合。然而，大多数多主元合金含有昂贵的金属和稀土元素，这可能会限制它们的适用性。在此，提出了一种低成本AlCrTiFeNi多主元合金的新颖设计，以研究结构、变形行为和微观机制之间的关系。通过原子尺寸差异、混合焓ΔHmix和价电子浓度（VEC）对单相AlCrTiFeNi进行的这种结构预测表明，我们可以选择体心立方结构的固溶体来设计AlCrTiFeNi多主元合金。通过对单相进行密度泛函理论计算（DFT）的结构稳定性预测已经证实，最有利的原子占据位置是(FeCrNi)(AlFeTi)。实验结果表明，AlCrTiFeNi多主元合金的结构是bcc1 + bcc2 + L相，我们认为这是其高强度的根本原因。我们的研究结果提供了一条新途径，通过基于理论预测、第一性原理计算和实验验证来设计和获得具有目标性能的多主元合金。
