Effect of composition and nanostructure on the mechanical properties and thermal stability of Zr100-xCux thin film metallic glasses

•The mechanical properties and thermal stability of nanostructured columnar Zr100-xCux thin film metallic glasses were investigated and compared to those of homogeneous films.•Crystallization temperature, hardness and elastic modulus were found to be mostly dependent on composition and local atomic order rather than from film nanostructure.•Viscoplastic behavior show high influence on both film composition and nanostructure, with columnar Zr-rich films showing higher tendency toward serrated flow deformation.•Resistance to cracking is higher for Cu-rich and homogeneous films thanks to the higher density of full icosahedral atomic packing, while interfaces favored crack initiation.