Metallic glasses: Deciphering their atomic choreography
Did you know that the strongest known engineering alloy is a metallic glass? This and many other world records have emerged along the success story of amorphous metals. With their unique structural and functional properties, and arising from a vast structural design space, metallic glasses are the amorphous counterpart to the high-entropy alloys paradigm. Sixty years after their discovery, metallic glasses have matured to industrial applications, but our structural understanding remains far behind. Presently, the advent of novel structural and dynamical probing methods, combined with new theoretical and modeling approaches, allow for the first time a one-to-one mapping of structure and structural dynamics. These developments emphasize medium-range order, extended network formation, and distinct structural partitioning in long-sought depth and detail for atomically disordered solids. Such a new view on metallic-glass microstructure and dynamics bears the promise of unifying numerous macroscopically observed phenomena, including negative creep, enthalpy recovery, stress-driven rejuvenation, and many more. This issue of MRS Bulletin aims at highlighting these advances, their promise to predictively understand macroscopic behavior, and to formulate reliable descriptors for structure and dynamics and for structure–property relationships of glassy materials. Metallic glasses are outstanding metallic alloys that combine the best properties from glassy solids and crystalline engineering alloys. This article introduces the current state-of-the-art and projects the future of structure and dynamics research of metallic glasses. As an overview article, it sets the stage for a series of subsequent focused contributions in this special issue Metallic glasses are outstanding metallic alloys that combine the best properties from glassy solids and crystalline engineering alloys. This article introduces the current state-of-the-art and projects the future of structure and dynamics research of metallic glasses. As an overview article, it sets the stage for a series of subsequent focused contributions in this special issue