| Designing Metallic Glasses and Heterophase Materials for Engineering Applications Juergen Eckert1; 1ERICH SCHMID INSTITUTE OF MATERIALS SCIENCE, Leoben, Austria; PAPER: 70/SISAM/Regular (Oral) SCHEDULED: 14:00/Fri. 25 Oct. 2019/Dr. Christian Bernard ABSTRACT: The structure of glasses is generally taken to be isoconfigurational, although it is well-known that the details of structure arrangement strongly depend on the temperature-time history experienced while establishing the glassy state. Recent studies of glass-forming metallic systems have revealed intriguing complexity, e.g. unusual shifts in radial distribution functions with temperature change or upon mechanical loading in the elastic or plastic regime. Nearest neighbour distances and medium-range order structural arrangements appear to change, e.g. shorten upon heating or become larger with decreasing temperature. Concomitantly, temperature changes as well as static or dynamic mechanical loading within the nominally elastic regime can trigger significant changes in glass properties, which are directly correlated with local non-reversible configurational changes due to non-affine elastic or anelastic displacements. All these findings strongly suggest that the characteristics of the atomic structure decisively determine the properties of the glass and of nanostructured materials derived from glass-forming systems. Recent findings and developments along this line will be summarized. Results from high-energy synchrotron x-ray radiation investigations at different temperatures and after mechanical loading will be related to the atomic structure of the material. It will also be related to its dependence on temperature, mechanical load as well as intrinsic heterogeneities and length-scale modulation to elucidate the correlation between atomic arrangement and mechanical or magnetic properties. References: 1. Ashby, M.F., Greer, A.L.: Metallic glasses as structural materials. Scripta Materialia 54, 321 (2006). 2. Cubuk, E.D., et al: Structure-property relationships from universal signatures of plasticity in disordered solids. Science 358, 1033 (2017). 3. Scudino, S., Shakur Shahabi, H., Stoica, M., Kaban, I., Escher, B., Kühn, U., Vaughan, G.B.M., Eckert, J.: Structural features of plastic deformation in bulk metallic glasses. Applied Physics Letters 106, 031903 (2015). 4. Sarac, B., Zhang, L., Kosiba, K., Pauly, S., Stoica, M., Eckert, J.: Towards the better: Intrinsic property amelioration in bulk metallic glasses. Scientific Reports 6, 27271 (2016). 5. Bian, X.L., Wang, G., Yi, J., Jia, Y.D., Bednarcik, J., Zhai, Q.J., Kaban, I., Sarac, B., Mühlbacher, M., Spieckermann, F., Keckes, J., Eckert, J.: Atomic origin for rejuvenation of a Zr-based metallic glass at cryogenic temperature. Journal of Alloys and Compounds 718, 254 (2017). 6. Sarac, B., Ivanov, Y.P., Chuvilin, A., Schöberl, T., Stoica, M., Zhang, Z., Eckert, J.: Origin of large plasticity and multiscale effects in iron-based metallic glasses, Nature Communications 9, 1333 (2018). |
