Amorphous alloys or bulk metallic glasses (BMGs) and their matrix composites (BMGMCs) are an emerging family of high-performance engineering materials that are ready to make a significant impact in a wide range of applications. Our fully and partially vitrified BMGs and BMGMCs offer a suite of desirable mechanical properties such as ultra high strength, high hardness, high elastic limit, good wear properties, and fatigue resilience, and can have additional useful properties integrated such as improved fracture toughness, enhanced ductility, excellent resistance to high temperature and corrosion, and low density.