Linking the pressure dependence of the structure and thermal stability to {\alpha}- and \b{eta}-relaxations in metallic glasses

Jie Shen; Antoine Cornet; Alberto Ronca; Eloi Pineda; Fan Yang; Jean-Luc Garden; Gael Moiroux; Gavin Vaughan; Marco di Michiel; Gaston Garbarino; Fabian Westermeier; Celine Goujon; Murielle Legendre; Jiliang Liu; Daniele Cangialosi; Beatrice Ruta

arXiv · 2501.11026

Linking the pressure dependence of the structure and thermal stability to {\alpha}- and \b{eta}-relaxations in metallic glasses

Jie Shen·Antoine Cornet·Alberto Ronca·Eloi Pineda·Fan Yang·Jean-Luc Garden·Gael Moiroux·Gavin Vaughan·Marco di Michiel·Gaston Garbarino·Fabian Westermeier·Celine Goujon·Murielle Legendre·Jiliang Liu·Daniele Cangialosi·Beatrice Ruta

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Abstract

Glasses derive their functional properties from complex relaxation dynamics that remain enigmatic under extreme conditions. While the temperature dependence of these relaxation processes is well-established, their behavior under high-pressure conditions remains poorly understood due to significant experimental difficulties. In this study, we employ cutting-edge experimental techniques to probe the pressure evolution of the relaxation spectrum in a Zr46.8Ti8.2Cu7.5Ni10Be27.5 metallic glass across gigapascal pressure ranges. Our findings reveal two distinct relaxation mechanisms under high pressure: In the \b{eta}-relaxation regime, compression drives the system with reduced atomic mobility and enhanced structural disorder, without significant density changes. Conversely, {\alpha}-relaxation under pressure promotes density-driven structural ordering that improves thermal stability. Notably, the transition between these regimes occurs at a constant T/Tg,P ratio, independent of applied pressure. These results provide crucial insights for decoupling the competing structural and relaxation contributions to glass stability, establishing a systematic framework for tailoring glass properties through controlled thermo-mechanical processing.

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Jie Shen, Antoine Cornet, Alberto Ronca, Eloi Pineda, Fan Yang, Jean-Luc Garden, Gael Moiroux, Gavin Vaughan, Marco di Michiel, Gaston Garbarino, Fabian Westermeier, Celine Goujon, Murielle Legendre, Jiliang Liu, Daniele Cangialosi, Beatrice Ruta. 2025-01-19. Linking the pressure dependence of the structure and thermal stability to {\alpha}- and \b{eta}-relaxations in metallic glasses. https://arxiv.org/abs/2501.11026

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