Multiscale observation of nano-oxide particles in oxide-dispersion-strengthened Cu alloys
Toshiki Saito, Hao Yu, Zimo Gao, Koji Inoue, Sosuke Kondo, Ryuta Kasada, Yasuyoshi Nagai, Yojiro Oba, Kosuke Hiroi
Abstract
Cu alloys with high durability and high thermal and electric conductivities are the key to achieving a more energetically efficient and eco-friendly future. Noble Zr-added oxide-dispersion-strengthened Cu alloys (ODS-Cu) with high strengths are promising materials for meeting all future service requirements. In this study, three-dimensional atom probe (3D-AP) and transmission electron microscopy (TEM) revealed that the majority of nano-oxide particles in the Zr-added ODS-Cu were novel yttria-stabilized zirconia (YSZ) particles with a diameter of less than 4 nm, which were completely different from Y2Zr2O7 and Y4Zr3O12 observed in other Zr-added ODS alloys. Multiscale observations including small-angle X-ray scattering (SAXS), 3D-AP, and TEM were performed to clarify the morphology of the oxide particles in the Zr-added ODS-Cu. Further strength enhancement through microstructural homogenization and specific incremental strength values were proposed.