Structure and mechanical properties of Cu-X (X = Nb,Cr,Ni) nanolayered composites

Journal Article · Tue Aug 04 04:00:00 EDT 1998 · Scripta Materialia

DOI:https://doi.org/10.1016/S1359-6462(98)00196-1· OSTI ID:651151

Misra, A; Verdier, M; Lu, Y C; Kung, H; Mitchell, T E; Nastasi, M; Embury, J D ^[1]

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1. Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

Sputtered Cu/Cr and Cu/Nb multilayers have polycrystalline microstructures with nanometer scale grain sizes, while Cu/Ni multilayers evaporated on single crystal Cu or NaCl were single crystalline. The hardness of the multilayers for layer thicknesses (h) > 50 nm is explained by Hall-Petch model with grain boundaries and interfaces as barriers. At h < 50 nm, a deviation from the Hall-Petch behavior is observed for all three composites. In this regime, plastic flow is believed to occur by single dislocations gliding on closely spaced planes with flow stress proportional to (1/h)ln(h/b). High hardnesses in nanolayered composites result from a combination of increased yield strength and increased work hardening rate at low h.

• OSTI ID: 651151
• Report Number(s): CONF-980202--
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 4-5 Vol. 39; ISSN 1359-6462; ISSN SCMAF7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM
COMPOSITE MATERIALS
COPPER
DISLOCATIONS
GRAIN SIZE
HARDNESS
MICROSTRUCTURE
NICKEL
NIOBIUM
PLASTICITY
STRAIN HARDENING