均匀化处理对7050铝合金ECAP的成形性影响机制  

Influence Mechanism of Homogenization Treatment on Formability of 7050 Aluminum Alloy during ECAP

作　　者：贾东昇 何涛 杜向阳 霍元明 JIA Dongsheng;HE Tao;DU Xiangyang;HUO Yuanming(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)

机构地区：[1]上海工程技术大学机械与汽车工程学院,上海201620

出　　处：《热加工工艺》2025年第6期93-98,共6页Hot Working Technology

基　　金：国家重点研发项目(2018YFB1307900);上海市自然基金项目(20ZR1422100);上海市人才发展资项目(2019022)。

摘　　要：针对7XXX系铝合金在等通道转角挤压(ECAP)性能提升过程中存在的载荷数值高、变形不均匀等问题,通过DEFORM-3D有限元软件模拟了铸态、465℃/24 h-炉冷、465℃/24 h-水冷、465℃/24 h+475℃/4 h-炉冷以及465℃/24 h+475℃/4 h-水冷5种不同制度处理后7050铝合金的ECAP成形过程,分析了不同状态铝合金在ECAP过程中载荷的数值及变化规律、等效应变的分布规律,解释了均匀化处理对7050铝合金ECAP成形性的影响机制。结果表明:与其他均匀化制度相比,双级均匀化水冷处理后的挤压峰值载荷最高,为9.2 t,归因于细小弥散相颗粒对位错的钉扎作用;双级均匀化炉冷处理后的挤压峰值载荷最低,为6.6 t,原因是细小弥散相颗粒发生粗化;双级均匀化炉冷处理后材料的应变均匀性最好,内角与中间位置的最大应变差为0.025,比其他状态下降了50%~60%。In order to alleviate the problems such as high load value and inhomogeneous deformation during equal channel angular pressing(ECAP),which can improve the mechanical properties of 7XXX series aluminum alloys,ECAP forming process of 7050 aluminum alloy with five different homogenization treatment methods including as-cast,465℃/24 h-furnace cooling,465℃/24 h-water cooling,465℃/24 h+475℃/4 h-furnace cooling and 465℃/24 h+475℃/4 h-water cooling were simulated by DEFORM-3D finite element software.The distribution and change law of extrusion load and equivalent strain of aluminum alloys in different states during ECAP process were analyzed.The effect mechanism of homogenization treatment on the ECAP formability of 7050 aluminum alloy was explained.The results show that compared with other states,peak extrusion load under the double-stage homogenization with water cooling treatment is highest as 9.2 t because of the pinning effect to dislocations of fine dispersed phases;peak extrusion load under the double-stage homogenization with furnace cooling treatment is owest as 6.6 t because that the fine dispersed phases are coarsened during the furnace cooling process;the distribution of effective strain under the double-stage homogenization with air cooling treatment is best,and the effective strain difference between the inner corner and the middle position of the material are 0.025,which decreases by about 50%-60% compared with other treatment system.

关 键 词：等通道转角挤压 7050铝合金 挤压载荷 不均匀变形 

分 类 号：TG166.3[金属学及工艺—热处理]