Microstructures and boundary distributions in Al polycrystals rolled at different temperatures

作者：Zhang XM^*; Deng YL; Liu Y; Tang JG; Zhou ZP

来源：Acta Metallurgica Sinica, 2005, 41(9): 947-952.

• Al polycrystal
• rolled
• microstructure
• boundary
• orientation
• Taylor factor

The orientation imaging micrographs (OlMs) in high purity aluminum rolled to 80% under room temperature and 180 degrees C were investigated using the SEM-EBSD technique. It was found that the elongated bands parallel to the rolling direction (RD) have two morphologies-the orientation concentrated and the orientation scattered, the orientations of the former mainly rotated toward beta-fibre, and the area fraction of the low angle (2 degrees-5 degrees) boundaries in the bands with the Br-({011}(211]) orientation was about 10%-15% larger than those of the S-({123}(634]) and C-({112}(111]) orientations. When the rolling temperature changed from the room temperature to 180 V, the area fraction of the middle angle (5 degrees-15 degrees) boundaries was increased by about 10% because of stronger recovery during rolling at 180 degrees C. The energy difference of the boundary distributions for the orientations along the beta-fibre has been analyzed in term of Bishop-Hill crystal plasticity theory. It is shown that the orientations with smaller values of Taylor factor M and larger combination numbers of 5 independent active systems correspond to less boundary energy and lower angle boundary during rolling.

• 出版日期2005-9
• 单位中南大学