Pressure–temperature route from disordered BCC to a 2 × 2 × 2 B2 superstructure

作者：Raimundas Sereika, Andrew D. Pope, C.G. Knight, Kallol Chakrabarty, Yogesh K. Vohra · 发表于：Scientific Reports · 年份：2025 · DOI：10.1038/s41598-025-33729-6 · 被引用次数：1 · 研究领域：High Entropy Alloys Studies、Intermetallics and Advanced Alloy Properties、Boron and Carbon Nanomaterials Research

The interplay between configurational entropy and the enthalpy of ordered structures governs phase stability in compositionally complex alloys. In the refractory alloy Re 0.6 (NbTiZrHf) 0.4 , this balance is particularly delicate: pressure stabilizes a disordered body-centred-cubic (bcc) solid solution over the ambient hexagonal Laves phase via a martensitic route. Using in situ laser heating with synchrotron X-ray diffraction in a diamond-anvil cell, we demonstrate that the metastable bcc phase can be controllably transformed into a large-scale 2 × 2 × 2 B2-type superstructure with primitive-cubic symmetry ( \(\:Pm\stackrel{-}{3}m\) ). This long-period ordered phase is crystallographically distinct from conventional B2 ordering in multicomponent alloys, establishing a pathway to achieve chemical ordering from pressure-stabilized solid solutions. More broadly, these findings demonstrate that combining compression with subsequent thermal activation can unlock recoverable three-dimensional superstructures, offering new opportunities to tailor strength, transport properties, and stability in compositionally complex alloys.