中國(guó)有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 27 No. 5 May 2017 |
（Department of Materials Science and Engineering, Norwegian University of Science and Technology, Trondheim 7491, Norway）
Abstract:Two aluminum alloys, Al-8Zn and Al-6Bi-8Zn were subjected to equal channel angular pressing (ECAP) up to 5 passes at room temperature. The microstructural evolution and the grain refinement behavior of these alloys were systematically studied by electron backscatter diffraction (EBSD). After 5 passes of ECAP, ultrafine grained microstructures formed in both alloys. However, the grain structure in the Al-6Bi-8Zn alloy is much finer than that of Al-8Zn alloy, showing that the soft Bi particles have a strong influence on enhancing the grain refinement during ECAP. The strengths of the ECAP-processed materials were measured by hardness test and it showed that after 5 passes of ECAP, the hardness of the Al-6Bi-8Zn alloy was higher than that of the Al-8Zn alloy. The effects of soft Bi particles on the deformation behavior during ECAP and the final strength of the Al-6Bi-8Zn alloy were discussed.
Key words: Al alloys; equal channel angular pressing (ECAP); Bi particle; grain refinement; hardness
