Cast defects induced sample-size dependency on compressive strength and fracture toughness of Mg-Cu-Ag-Gd bulk metallic glass

► We investigate specimen-size dependency of fracture strength and toughness of Mg BMG. ► Cast defects result in a reduction of fracture strength as sample diameter increases. ► Cast defects result in a reduction of notch toughness as plate thickness increases. ► FEA confirms size effect is not caused by plane-stress to plane-strain transition.