中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 22 No. 11 November 2012 |
（1. Research Center for Analysis and Measurement, Kunming University of Science and Technology,
Kunming 650093, China;
2. Key Lab of Advanced Materials in Rare and Precious and Non-ferrous Metals of Ministry of Education,
Kunming University of Science and Technology, Kunming 650093, China;
3. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology,
Kunming 650093, China）
Abstract:The initial copper with large grain sizes of 60-100 μm was processed by six passes asymmetrical accumulative rolling-bond (AARB) and annealing, the ultra-fine-grained (UFG) copper with grain size of 200 nm was obtained, and the microstructures and properties were studied. The results show that there are large sub-structures and also texture component C for the UFG copper obtained by six passes AARB, possessing high strength and microhardness in company with poor elongation and conductivity. Thereafter, the UFG copper was annealed at 220 °C for 35 min, in which the sub-structures disappear, the grain boundaries are composed of big angle grain boundaries, and the textures are composed of a variety of texture components and parts of twins. Compared with the UFG copper obtained by six passes AARB, the tensile strength and yield strength for the UFG copper obtained by six passes AARB and annealing at 220 °C for 35 min are decreased slightly, the elongation and conductivity are improved obviously.
Key words: ultra-fine-grain copper; asymmetrical accumulative rolling-bond; annealing; formation mechanism; organizational controlling; elongation; conductivity
