Nanoglass–Nanocrystal Composite - a Novel Material Class for Enhanced Strength–Plasticity Synergy

The properties of a material can be engineered by manipulating its atomic and chemical architecture. Nanoglasses which have been recently invented and comprise nanosized glassy particles separated by amorphous interfaces, have shown promising properties. A potential way to exploit the structural benefits of nanoglasses and of nanocrystalline materials is to optimize the composition to obtain crystals forming within the glassy particles. Here, a metastable Fe‐10 at% Sc nanoglass is synthesized. A complex hierarchical microstructure is evidenced experimentally at the atomic scale. This bulk material comprises grains of a Fe$_{90}$Sc$_{10}$ amorphous matrix separated by an amorphous interfacial network enriched and likely stabilized by hydrogen, and property‐enhancing pure‐Fe nanocrystals self‐assembled within the matrix. This composite structure leads a yield strength above 2.5 GPa with an exceptional quasi‐homogeneous plastic flow of more than 60% in compression. This work opens new pathways to design materials with even superior properties.