Glass formation in pure metals

If the cooling rate is sufficiently fast, it is thought that any metallic liquid can be frozen into a glassy state, which can in turn yield a solid metal with unusual and potentially useful mechanical properties. In practice, such glass formation is mainly limited to metals composed of two or more elements: the cooling rates required to produce a monatomic metallic glass are usually too high to be achieved experimentally. Li Zhong et al. have found a way around this experimental difficulty. They have developed a nanoscale heating system in which a pulsed electrical current can locally melt the metal (briefly forming a small volume of metallic liquid), which then rapidly loses its heat into the surrounding solid bulk and leaves behind a sample of monatomic metallic glass amenable for study of its structure and properties.