Role of minor additions on metallic glasses and composites

Microalloying refers to the addition of a small concentration of an alloying element to tune the properties of the parent alloy. Microalloying technology enables to control the glass formation and the mechanical properties of bulk metallic glasses (BMGs). This manuscript presents a comprehensive review on recent developments and breakthroughs in the field of microalloying for tuning the properties of BMGs and composites with focus on the results. The ability of multiple element co-addition to optimize the glass formation and the importance of future alloy developments have been highlighted. Proper microalloying can be used to tailor not only the mechanical properties of the amorphous phase but also those of the crystalline phase, which opens up the possibility for tuning the mechanical performance at different length scales. The effectiveness in controlling the mechanical performance through microalloying was shown to greatly depend on the alloy composition and closeness to the critical amorphous diameter. A tentative outlook commenting the potential and challenges of this exciting field of research is also presented.