Nanocrystallitzation of metallic glasses and subsequent structure changes in the resulted nanomaterials

Dmitri V. Louzguine

Mathematics for Advanced Materials-OIL, AIST-Tohoku University

WPI Advanced Institute for Materials Research, Tohoku University

Various nanostructures formed by crystallization metallic glasses either on heating or by deformation  (see Fig. 1, for example) will be presented here. Such processes lead to the formation of the samples with unique mechanical properties unattainable in the precursor materials. Thermal nanocrystallization leads to the formation of mixed phase glassy/crystalline or glassy/quasicrystalline structures in various bulk metallic glasses. This, in turn, leads to the improvement of plasticity of initially monolithic bulk metallic glasses. Kinetics of the crystallization process in metallic glasses including an early stage nucleation process [1], growth of nanoparticles [2] and subsequent structure coarsening will be reported. The process of phase separation which competes with crystallization will also be discussed [3].

Nano-structured metallic glasses consisting of glassy nanoparticles separated by glassy interfaces which possess enhanced chemical and magnetic properties owing to large surface area and small particles size will also be reported [4].  The formation of the nano-structured metallic glasses provides new insights in materials science offering the opportunity for further development of their physical and chemical properties.