Title | Creep resistance of bulk copper–niobium composites: An inverse effect of multilayer length scale |
Publication Type | Journal Article |
Year of Publication | 2019 |
Authors | Avallone JT, Nizolek TJ, Bales BB, Pollock TM |
Journal | Acta Materialia |
Volume | 176 |
Pagination | 189–198 |
ISSN | 13596454 |
Keywords | Creep, Cu-Nb, Length scale, Multilayer |
Abstract | Metallic multilayer systems show promising performance in extreme environments, with high stability of bi-metal interfaces down to nanometer length scales. The creep behavior of bulk, accumulative roll bonded (ARB) Copper–Niobium (Cu–Nb) composites has been studied at 400 °C as a function of layer thickness, ranging from 2 μm to 65 nm. Similar to single phase metallic systems, three regimes are observed during creep: transient, steady-state and tertiary. The mechanism controlling minimum creep rate for all conditions tested has a strong dependence on stress, consistent with dislocation-dominated creep. Unlike the conventional effect of grain size on creep resistance, this study reveals that decreasing length scale increases creep resistance. |
URL | https://doi.org/10.1016/j.actamat.2019.06.029 |
DOI | 10.1016/j.actamat.2019.06.029 |