title: Structural evolution and strain induced mixing in Cu-Co composites studied by transmission electron microscopy and atom probe tomography.
abstract: A Cu-Co composite material is chosen as a model system to study structural evolution and phase formations during severe plastic deformation. The evolving microstructures as a function of the applied strain were characterized at the micro-, nano-, and atomic scale-levels by combining scanning electron microscopy and transmission electron microscopy including energy-filtered transmission electron microscopy and electron energy-loss spectroscopy. The amount of intermixing between the two phases at different strains was examined at the atomic scale using atom probe tomography as complimentary method. It is shown that Co particles are dissolved in the Cu matrix during severe plastic deformation to a remarkable extent and their size, number, and volume fraction were quantitatively determined during the deformation process. From the results, it can be concluded that supersaturated solid solutions up to 26 at.% Co in afccCu-26 at.% Co alloy are obtained during deformation. However, the distribution of Co was found to be inhomogeneous even at the highest degree of investigated strain.
authors.affiliation: Chair of Materials Science and Methods, Saarland University, Saarbrücken, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Bachmaier
authors.affiliation: Chair of Functional Materials, Saarland University, Saarbrücken, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Aboulfadl
authors.affiliation: INM-Leibniz Institute for New Materials, Saarbrücken, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Pfaff
authors.affiliation: Chair of Functional Materials, Saarland University, Saarbrücken, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Mücklich
authors.affiliation: Chair of Materials Science and Methods, Saarland University, Saarbrücken, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Motz
keywords: Atom probe tomography; Cu–Co; High-pressure torsion; Mechanical alloying; Microstructure; Nano-composite; Transmission electron microscopy