Work

Three-dimensional network of multi-fold twins enabled by geometrically necessary amorphous zones

Year: 2025

Type: article

Abstract: Three-dimensional multi-fold twin architectures are valuable for tailoring material properties but constructing them in man-made crystals remains challenging due to angular misfits from incomplete 360° space filling in large volumes, particularly lacking in-situ observations of crystal growth. Here, we successfully create three-dimensional architectures of plural multi-fold twins in a growing FeCoNiCuZn and the other multi-principal element alloy. The inherent chemical composition inhomogeneity entails twin fault energy variation across different {111} twinning planes, activating multiple twinning systems simultaneously. Importantly, we discover the commonly existed geometrically necessary amorphous zones in such three-dimensional multi-fold twin architectures. Combining in-situ transmission electron microscopy heating experiments and atomic electron tomography, we find that these geometrically necessary amorphous zones, typically several nanometers in size, fill the twin junctions and accommodate large geometric misfits, preventing crystallization even near the melting point. The construction of three-dimensional networks of multi-fold twins is limited by angular misfits in large crystals. Here, this study reveals the atomic-scale growth of such architectures in FeCoNiCuZn alloys, stabilized by amorphous zones at twin junctions.

Source: Nature Communications

DOI: 10.1038/s41467-025-66378-4