Transformation-induced plasticity is a fundamental solution for improving the ductility of bulk metallic glass composites (BMGCs). However, the underlying mechanism remains controversial. Here, by using in situ transmission electron microscopy, we present direct observation of the transformation dynamics from β/ω phase to α’ phase of the crystalline dendrites in a TiZrCuBe BMGC under uniaxial tensile deformation. The transformation redistributes the stress in the adjacent matrix, making interfacial regions potential preferential sites for shear band nucleation. The high density of nucleation sites is believed to promote the formation of shear band networks and enhance the ductility of BMGCs.

转变诱导的可塑性是提高块状金属玻璃复合材料（BMGC）延展性的基本解决方案。但是，其潜在机制仍存在争议。在这里，通过使用原位透射电子显微镜，我们可以直接观察到TiZrCuBe BMGC在单轴拉伸变形下从晶体的β / ω相到α'相的转变动力学。该转变将应力重新分布在相邻基体中，使界面区域成为剪切带形核的潜在优先位置。据信高密度的成核位点可促进剪切带网络的形成并增强BMGC的延展性。