发表机构
Federal University of São Carlos; Uppsala University; Wallenberg Initiative Materials Science for Sustainability, Uppsala University; Massachusetts Institute of Technology; The University of Manchester; Baylor University; AF Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB（圣卡洛斯联邦大学; 乌普萨拉大学; 乌普萨拉大学瓦伦堡可持续发展材料科学倡议; 麻省理工学院; 曼彻斯特大学; 贝勒大学; 赖特-帕特森空军基地材料与制造局空军研究实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究Co30Cr40Ni30合金中化学短程有序（CSRO）对变形机制的影响，通过对比淬火和时效状态，结合量热法、衍射及显微镜等手段，辅以原子模拟，证实CSRO是调节堆垛层错能、控制变形路径的额外自由度。
AI 中文摘要
化学短程有序（CSRO）是复杂集中合金（CCA）的固有特征，但其对变形机制的影响存在争议，因为变形过程中CSRO量化尚无定论。本文提供实验证据表明，CSRO在Co30Cr40Ni30合金中作为控制堆垛层错能和变形路径的固有热力学状态变量。通过比较具有等效晶粒结构和相组成的淬火（贫CSRO）和时效（富CSRO）条件，分离出原子尺度化学有序对力学行为的影响。量热法证实CSRO形成可逆，同步加速器X射线衍射和电子显微镜表明CSRO在室温和低温下均抑制变形诱导的fcc-hcp马氏体转变。尽管转变动力学不同，但宏观拉伸响应仍大致相似。原子模拟表明CSRO增加了稳定和不稳定堆垛层错能，提高了部分位错活动的能垒并稳定了fcc晶格以防止转变。实验和计算结果共同确立了CSRO作为调节堆垛层错能和控制复杂集中合金变形路径的额外自由度。
英文摘要
Chemical short-range order (CSRO) is an intrinsic feature of complex concentrated alloys (CCAs), yet its influence on deformation mechanisms is controversial because of the inconclusive state of concurrent CSRO quantification during deformation. Here, we provide experimental evidence that CSRO acts as an intrinsic thermodynamic state variable governing stacking-fault energetics and deformation pathways in a Co30Cr40Ni30 alloy. By comparing quenched (CSRO-lean) and aged (CSRO-enriched) conditions with equivalent grain structure and phase constitution, we isolate the influence of atomic-scale chemical ordering on mechanical behavior. Calorimetry confirms reversible CSRO formation, while synchrotron X-ray diffraction and electron microscopy reveal that CSRO suppresses deformation-induced fcc-hcp martensitic transformation at both room and cryogenic temperatures. Despite differences in transformation dynamics, the macroscopic tensile response is still broadly similar. Atomistic simulations show that CSRO increases both stable and unstable stacking-fault energies, raising the energetic barrier for partial-dislocation activity and stabilizing the fcc lattice against transformation. Together, the experimental and computational results establish CSRO as an added degree of freedom for tuning stacking-fault energetics and controlling deformation pathways in complex concentrated alloys.
Comments22 pages, 7 figures, 8 supplementary information figures, 46 references
