In-situ observations on shear-banding process during tension of a Zr-based bulk metallic glass composite with dendrites

•The shear-banding process in a Zr-based MG composite is observed.•The shear band originates from MG matrix at its interface with the dendrites.•The shear band multiplies in the MG matrix between dendrites.•Dendrites change propagation direction of shear bands or terminate it within them. In-situ quasistatic tension experiments inside scanning electron microscope were performed to study shear-banding behaviors of a Zr-based bulk metallic glass composite with the 50% volume fraction of dendritic phases. It was observed that the shear band initiates at the interface of metallic glass matrix and dendrites, and then propagates in the glass matrix. Dendrites change the propagation direction of shear bands or terminate the shear band within them. Both modes facilitate the multiplication of shear bands in the glass matrix between dendrites. Upon further loading, shear bands preferentially develop into cracks in the matrix, but the dendrites significantly improve the crack resistance. This work provides the first-hand information of shear-banding and failure of the Zr-based metallic glass composite with dendrites.