Multiscale observation of nano-oxide particles in oxide-dispersion-strengthened Cu alloys

Saito, Toshiki*; Yu, H.*; Gao, Z.*; Inoue, Koji*; Kondo, Sosuke*; Kasada, Ryuta*; Nagai, Yasuyoshi*; Oba, Yojiro*; Hiroi, Kosuke  

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 YZrO and YZrO 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.