Enhanced plasticity by introducing icosahedral medium-range order in ZrCuNiAl metallic glass

The deformation behavior of the Zr69.5Cu12Ni11Al7.5 bulk metallic glass (BMG) was examined by compression, tension and three-point bending test. It was found that the BMG exhibits excellent room temperature plasticity and toughness with a compressive strain over 11.5%, a tension strain of about 0.2–0.3% and a notch toughness of 86 ± 5.5 MPa m1/2. Structural analyses revealed that the existence of strong icosahedral medium-range order (IMRO) clusters in amorphous phase, which contributes to the good plasticity and toughness of the BMG studied.

► Zr69.5Cu12Ni11Al7.5 metallic glass exhibits excellent plasticity and toughness.
► The compressive strain is over 11.5% and tension strain of about 0.2–0.3%.
► The notch toughness is 86 ± 5.5 MPa m1/2.
► There is a strong icosahedral medium-range order clusters in amorphous phase.
► There is no crystallization in shear band during plastic deformation.