TMS 2020 Annual Meeting & Exhibition, California, United States Of America, 23 - 27 February 2020, pp.1
Nanolayered metallic glass-crystalline structures provide an effective approach to improving the low ductility of monolithic metallic glasses. Previous work on metallic glass-FCC crystalline nanolayers has shown that the strength of these nanolayers is dominated by the response of the softer crystalline phase. As a result, the strength increases with decreasing layer thickness, resembling the Hall-Petch behavior. In this work, we investigated metallic glass-HCP crystalline nanolayers such as CuTi/Ti and CuZr/Zr, and observed that the strength does not vary with layer thickness. Furthermore, the strength is virtually the same as that of the corresponding monolithic metallic glass (CuZr and CuTi). We attribute this interesting behavior to the higher strength of the HCP phase when compared to the metallic glass, as predicted by the confined-layer slip model. The results show that the mechanical behavior of metallic glass-crystalline composites strongly depends on the crystal structure and the relative strengths of the layers.