Creep Resistance of Bulk Copper-Niobium Composites: an Inverse Effect of Multilayer Length Scale

Journal Article · Sat Jun 22 00:00:00 EDT 2019 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2019.06.029· OSTI ID:1530774

Avallone, Jaclyn T. ^[1]; Nizolek, Thomas Joseph  ^[2]; Bales, Benjamin B. ^[1]; Pollock, Tresa Marie ^[1]

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1. Univ. of California, Santa Barbara, CA (United States)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

We present that 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 2μm to 65μm. 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. Additionally, unlike the conventional effect of grain size on creep resistance, this study reveals that decreasing length scale increases creep resistance.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of California, Santa Barbara, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); Laboratory Directed Research & Development (LDRD)
• Grant/Contract Number: 89233218CNA000001; NA0003857
• OSTI ID: 1530774
• Alternate ID(s): OSTI ID: 1668304; OSTI ID: 1780365
• Report Number(s): LA-UR-18-21753
• Journal Information: Acta Materialia, Vol. 176; ISSN 1359-6454
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Cu-Nb
Creep
Multilayer
Length Scale