Strain mapping of plastically-deformed bulk metallic glasses
The unique experimental setup consisting of focused hard X-ray beam, large Q range and high resolution detector/camera permits to create spatially-resolved strain maps and allows to investigate the atomic rearrangements occurring in bulk metallic glasses as a result of room temperature plastic deformation. Through these investigations we have experimentally identify the overall structural signature of plastic deformation in metallic glasses, namely strong shear strain and considerable directional anisotropy. These findings are in contrast to the behavior observed for elastically-deformed BMGs, which instead display no significant shear component and directional anisotropy, marking a clear difference between elastic and plastic deformation of metallic glasses. These observations not only provide a direct experimental evidence of the effects of plastic deformation on the atomic structure of metallic glasses, but also may contribute to the understanding of how one can positively influence the formation and propagation of detrimental shear bands in order to mitigate the room temperature brittleness of bulk metallic glasses.
S. Scudino, H. Shakur Shahabi, M. Stoica, I. Kaban, B. Escher, U. Kühn, G.B.M. Vaughan, J. Eckert: “Structural features of plastic deformation in bulk metallic glasses”, Applied Physics Letters 106 (2015) 031903 URL