摘要
An Al−3.6Cu−1Li alloy was subjected to room temperature rolling and cryorolling to investigate their effects on microstructure evolution and mechanical properties.The microstructure and aging characteristics of the room temperature-rolled and the cryorolled alloys with 70%and 90%of thickness reductions were studied by microstructure analysis and mechanical tests.The samples subjected to cryorolling with 90%of thickness reduction have high strength and good toughness.This is mainly due to the inhibition of dynamic recovery and the accumulation of high-density dislocations in cryorolled samples.In addition,the artificial aging reveals that the temperature at which peak hardness is attained is inversely proportional to the deformation amount and directly proportional to the rolling temperature.Moreover,bright field images of cryorolled samples after aging indicate the existence of T1(Al2CuLi)precipitates.This suggests that the high stored strain energy enhances the aging kinetics of the alloy,which further promotes the nucleation of T1 phases.
对Al−3.6Cu−1Li合金进行室温轧制和深冷轧制,并研究工艺对材料显微组织演变和力学性能的影响。通过显微组织分析与力学性能测试,研究厚度压下率为70%和90%的室温轧制和深冷轧制样品的显微组织和时效特性。经过90%厚度压下率的深冷轧制样品具有高强度和良好的韧性,这主要是由于深冷轧制样品对动态回复的抑制和高密度位错的积累。人工时效研究结果表明,达到峰值硬度的温度与变形量成反比,与轧制温度成正比。此外,明场透射电子显微镜照片表明,时效处理的深冷轧制样品存在T1(Al2CuLi)相析出。研究表明,高存储的应变能增强合金的时效动力学,进而促进强化相形核。
作者
Chang LI
Han-qing XIONG
Laxman BHATTA
Lin WANG
Zhao-yang ZHANG
Hui WANG
Charlie KONG
Hai-liang YU
李畅;熊汗青;Laxman BHATTA;王琳;张朝阳;王辉;Charlie KONG;喻海良(中南大学高性能复杂制造国家重点实验室,长沙410083;中南大学机电工程学院,长沙410083;Research Center for Advanced Science and Technology,The University of Tokyo,Meguro,Tokyo 1530041,Japan;Electron Microscope Unit,University of New South Wales,Sydney,NSW 2052,Australia;中南大学轻合金研究院,长沙410083)
基金
Project(2019YFB2006500)supported by the National Key Research and Development Program of China
Project(51674303)supported by the National Natural Science Foundation of China
Project(2018RS3015)supported by the Huxiang High-Level Talent Gathering Project of Hunan Province,China
Project(2019CX006)supported by the Innovation Driven Program of Central South University,China
Project supported by the Research Fund of the Key Laboratory of High Performance Complex Manufacturing at Central South University,China。
