亚稳态固溶体转变为复杂纳米结构

Instability in a high-entropy alloy drives structural changes that strengthen the alloy Wenhao Sun and Amit Misra I n traditional alloys, strength often comes from an interplay of structural features such as precipi- tates, grain boundaries, and dislocations, which can range from nanometer to micrometer sizes. By contrast, in high-entropy alloys, near-equal ra- tios of five or more elements are homogeneously mixed in a solid state (solid solution) (1). The goal of achiev- ing uniformity in high-entropy alloys conflicts with long- standing principles of designed heterogeneity in metal- lurgy, in which hierarchical defects strengthen alloys by impeding dislocation motions across length scales. On page 1308 of this issue, Zhang et al. (2) report a strategy that bridges uniformity and heterogeneity. …