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选用经多向锻造和再结晶退火的晶粒组织均匀(平均晶粒尺寸为20 mm)且取向均匀的高纯Al(99.99%)为原料,将2组平行样品分别进行等效应变e≈2的等径角挤压(ECAP)和单向轧制(DR)变形后,再经360℃再结晶退火8~90 min,利用基于体视学原理和电子背散射衍射技术(EBSD)的五参数分析法(FPA)对比研究了不同变形方式对高纯Al退火再结晶晶界面取向分布的影响.结果表明,经变形及360℃退火后,2组样品中其再结晶晶界面主要取向于低能稳定的{111},并主要对应于以<111>为转轴的大角度扭转晶界.ECAP与DR样品退火后的主要差异在于,前者再结晶晶界面取向于{111}的过程较迟缓;后者再结晶晶界面比较容易取向于{111}.分析指出,DR变形更容易使高纯Al再结晶晶面取向于低能稳定的{111},更有益于晶界特征分布的优化.这与DR变形形成的<110>//ND织构导致其再结晶退火过程中晶粒容易长大有关.
High-purity Al (99.99%) with uniform grain structure (average grain size of 20 mm) and uniform orientation was selected as the raw material through multi-directional forging and recrystallization annealing, and the two parallel samples were respectively subjected to equivalent strain e≈2 (ECAP) and uniaxial rolling (DR) deformation, and then recrystallization annealing at 360 ℃ for 8 ~ 90 min, using the five parameters based on stereological principles and electron backscatter diffraction (EBSD) The effects of different deformation modes on the orientation distribution of the recrystallized grain boundary of high purity Al annealed were analyzed by using the analysis method (FPA). The results show that the recrystallized grain boundaries of the two samples are mainly oriented to low energy stability after deformation and annealing at 360 ℃ {111}, mainly corresponding to the large angle twist of the <111> axis.The main difference between the ECAP and DR samples after annealing is that the former recrystallization interface is slower than the latter at the {111} The recrystallized interface is easier to be oriented to {111}. It is pointed out that DR deformation is more likely to orient the high purity Al recrystallized plane to low energy stable {111}, which is more beneficial to the optimization of grain boundary distribution. The formed <110> // ND texture is responsible for the easy grain growth during recrystallization annealing.