Abstract:Metallic glasses (MGs), fabricated by a melt-quench method, possess many unique properties compared with conventional crystalline metals and alloys, including high fracture strength up to 6 GPa, the highest fracture toughness of 200 MPa?m1/2, large elastic limit (2%, the theoretical elastic limit), good corrosion and wear resistance. These superior properties of MGs have attracted tremendous attention scientifically and industrially. However, the following three key problems hinder the applications of MGs: (1) the relationship between the atomic-scale structures and physical properties of MGs; (2) enhancements in the ductility of MGs; (3) the fatigue mechanisms and improvement of the fatigue limit of MGs. In this review, we introduce the history, the formation process, major properties and applications, challenges, structural characterizations, and atomic-scale structural models of MGs. Then, the deformation and fracture mechanisms of MGs and some strategies used to improve the ductility of MGs are also described in detail. Last but not least, we review the fatigue behaviors of MGs and provide proposals for future work in the field of MGs.