3D FEM simulations and experimental validation of plastic deformation of pure aluminum deformed by ECAP and combination of ECAP and direct extrusion  

纯铝等径角挤压及等径角挤压和直接挤压结合的塑性变形3D有限元模拟和实验验证（英文）

作　　者：Mohamed Ibrahim Abd EL AAL 

机构地区：[1]Mechanical engineering Department College of Engineering, Prince Sattam Bin Abdulaziz University,Wadi Addawasir, Kingdom of Saudi Arabia [2]Mechanical Design & Production Department, Faculty of Engineering, Zagazig University, Zagazig, Egypt

出　　处：《Transactions of Nonferrous Metals Society of China》2017年第6期1338-1352,共15页中国有色金属学报（英文版）

摘　　要：Rigid-viscoplastic3D finite element simulations(3D FEM)of the equal channel angular pressing(ECAP),thecombination of ECAP+extrusion with different extrusion ratios,and direct extrusion of pure aluminum were performed andanalyzed.The3D FEM simulations were carried out to investigate the load-displacement behavior,the plastic deformationcharacteristics and the effective plastic strain homogeneity of Al-1080deformed by different forming processes.The simulationresults were validated by microstructure observations,microhardness distribution maps and the correlation between the effectiveplastic strain and the microhardness values.The3D FEM simulations were performed successfully with a good agreement with theexperimental results.The load-displacement curves and the peak load values of the3D FEM simulations and the experimentalresults were close from each other.The microhardness distribution maps were in a good conformity with the effective plastic straincontours and verifying the3D FEM simulations results.The ECAP workpiece has a higher degree of deformation homogeneity thanthe other deformation processes.The microhardness values were calculated based on the average effective plastic strain.Thepredicted microhardness values fitted the experimental results well.The microstructure observations in the longitudinal andtransverse directions support the3D FEM effective plastic strain and microhardness distributions result in different formingprocesses.对纯铝进行等径角挤压、等径角挤压结合不同挤压比直接挤压及直接挤压,并采用刚-粘塑性3D有限元模拟进行分析。利用3D有限元模拟研究不同成形过程变形Al-1080的载荷-位移行为、塑性变形特征和有效塑性应变均匀性。用显微组织观察、显微硬度分布图、有效塑性应变和显微硬度值验证模拟结果。结果表明:模拟结果与实验结果一致;模拟载荷-位移曲线和最大载荷与实验结果接近;显微硬度分布图符合有效塑性应变等高线,证实了3D有限元模拟结果。等径角挤压工件的变形均匀性程度比其他变形过程的高。根据平均有效塑性应变计算了显微硬度值。预测显微硬度值与实验结果吻合。横向和纵向显微组织观察验证了不同成形过程中3D有限元模拟有效塑性应变和显微硬度分布结果。

关 键 词：equal channel angular pressing (ECAP) EXTRUSION finite element method (FEM) MICROHARDNESS deformation homogeneity microstructure 

分 类 号：TG379[金属学及工艺—金属压力加工]