title: Design of exceptionally strong and conductive Cu alloys beyond the conventional speculation via the interfacial energy-controlled dispersion of γ-Al2O3 nanoparticles.
abstract: The development of Cu-based alloys with high-mechanical properties (strength, ductility) and electrical conductivity plays a key role over a wide range of industrial applications. Successful design of the materials, however, has been rare due to the improvement of mutually exclusive properties as conventionally speculated. In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled. We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes. It is shown that the Ti dramatically drives the interfacial phase transformation from very irregular to homogeneous spherical morphologies resulting in substantial enhancement of the mechanical property of Cu matrix. Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu. We validate experimental results using TEM and EDX combined with first-principles density functional theory (DFT) calculations, which all consistently poise that our materials are suitable for industrial applications.
authors.affiliation: Structural Materials Division, Korea Institute of Materials Science, Changwon, 51508, Korea.
authors.forename: Seung Zeon
authors.initials: SZ
authors.lastname: Han
authors.affiliation: School of Materials Science and Engineering, Pusan National University, Pusan, 46241, Korea.
authors.forename: Kwang Ho
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Energy Systems Engineering, DGIST, Daegu, 42997, Korea.
authors.forename: Joonhee
authors.initials: J
authors.lastname: Kang
authors.affiliation: Research and Development Division, KOS Ltd., Yangsan, 50592, Korea.
authors.forename: Hongrae
authors.initials: H
authors.lastname: Joh
authors.affiliation: Research and Development Division, Seowon, Ansan, 15599, Korea.
authors.forename: Sang Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Structural Materials Division, Korea Institute of Materials Science, Changwon, 51508, Korea.
authors.forename: Jee Hyuk
authors.initials: JH
authors.lastname: Ahn
authors.affiliation: Department of Materials Science and Engineering, Changwon National University, Changwon, 51140, Korea.
authors.forename: Jehyun
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Advanced Materials Science &Engineering, Kangwon National University, Chuncheon, 24341, Korea.
authors.forename: Sung Hwan
authors.initials: SH
authors.lastname: Lim
authors.affiliation: Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, 03722, Korea.
authors.forename: Byungchan
authors.initials: B
authors.lastname: Han