叠轧深变形制备超细晶Al-1%Mg合金

Manufacturing ultrafine-grained Al-1%Mg alloy by accumulative Roll-Bonding process

叠轧深变形技术具有商业化生产超细晶材料的潜力. 在叠轧等效应变为4 0的条件下得到了平均晶粒为0 5μm的Al 1%Mg合金超细晶组织; 在热作用下合金组织由亚稳定态向稳定态转化, 在退火温度高于200℃时晶粒变化明显, 在200℃以下, 晶粒生长比较缓慢; 随着退火温度的升高, 合金组织发生静态回复与静态再结晶过程, 静态回复是通过位错的滑移和攀移而进行的, 再结晶是通过亚晶合并生长而进行的.

Accumulative Roll-Bonding process has a potential application for commercial production of ultrafine-grained materials. Ultrafine-grained Al-1%Mg alloy in an average scale of 0.5μm was produced at an equivalent plastic strain of 4.0. Alloy microstructure evolves from metastable to stable state under thermal actions. When the annealing temperature is higher than 200℃, grain grows sharply, while the annealing temperature is lower than 200℃, grain grows slowly. With annealing temperature gradually increasing, static recovery and static recrystallization occur in the alloy. Static recovery is carried out by dislocation slipping and climbing, and recrystallization proceeds by subgrain coalescence and subgrain growth.