Mechanical characteristics of Mg–Cu–Zr thin film metallic glasses

For improving the ductility of metallic glasses, nanocrystals within the amorphous matrix are frequently intentionally added. In this study, the MgCuZr thin film metallic glasses (TFMGs) with a positive mixing heat between Mg and Zr are fabricated via co-sputtering in an attempt to separate the pure Mg nano-particles. The microstructure and mechanical properties of the sputtered MgCuZr thin films and their FIB-machined micropillars are examined as a function of Mg content from 39 to 100 at.%. From the nanoindentation and micropillar load–displacement curves, the Mg-rich metallic glass composites exhibit smoother nature and more ductile behavior. Meanwhile, due to strong (0002) basal texture, the Mg-rich thin films and micropillars possess strong modulus (~ 80 GPa), hardness (~ 3.5 GPa), and yield stress (~ 1.5 GPa), coupled with more ductile behavior. All of these would allow promising applications in micro-electro-mechanical systems.

► Strong and ductile amorphous MgZrCu thin-film composites ► Phase separated Mg nano-particles ► Microstructure and nanoindentation/micropillar mechanical behavior