DYNAMIC RECOVERY AND RECRYSTALLIZATION OF COMMERCIAL ALUMINIUM UNDER TORSION AT ELEVATED TEMPERATURES
SHEN Jian; (Department of Materials Science and Engineering; Central South University of Technology; Changsha 410083) ZHANG Xinming; ZHANG Siqi; YIN Zhimin; LU Bin (Central South University of Technology; Changsha 410083); SONG Hengzao; SHU Xianjin (Chengdu Seamless Steel Tube Mill; Chengdu 610069)
Cite this article:
SHEN Jian; (Department of Materials Science and Engineering; Central South University of Technology; Changsha 410083) ZHANG Xinming; ZHANG Siqi; YIN Zhimin; LU Bin (Central South University of Technology; Changsha 410083); SONG Hengzao; SHU Xianjin (Chengdu Seamless Steel Tube Mill; Chengdu 610069). DYNAMIC RECOVERY AND RECRYSTALLIZATION OF COMMERCIAL ALUMINIUM UNDER TORSION AT ELEVATED TEMPERATURES. Acta Metall Sin, 1995, 31(9): 411-416.
Abstract Hot torsion testing was conducted on commercial aluminium at 300-500℃ and constant surface strain rate of 5.0 s-1 to study the dynamic recovery and dynamic recrystallization. The microstructural observations under OM and TEM show that the dynamic recovery is the only operative restoration mechanism if the deformation temperatures are below 400℃, and substructure consists of approximately equiaxial subgrains.The material, however, is mainly softened by dynamic recrystallization when torsion temperatures exceed 450℃ . The fine and homogeneous recrystallized grains, which are different from the coarse initial grains, develops over the gauge length of the specimens after large strain of about 3.85.The essential features of the torsional equivalent stress-strain behaviours are consistent with that of periodically oscillating flow. A Hall-Petch relationship was satisfied by linear regression between the reciprocal of average diameter of subgrains and Zener-Hollomon parameters.
