多向锻造对Al-Zn-Mg-Cu合金缺陷消除及微观组织的影响  

Effect of Multi-directional Forging on Defect Elimination and Microstructure of Al-Zn-Mg-Cu Alloy

作　　者：魏德金 韩陆依 吕正风 谢撰业 韩兆玉 王广春[2] 赵国群[2] WEI Dejin;HAN Luyi;LÜZhengfeng;XIE Zhuanye;HAN Zhaoyu;WANG Guangchun;ZHAO Guoqun(Shandong Nanshan Aluminum Co.,Ltd.,Longkou 264000;Key Laboratory for Liquid-Solid Structure Evolution&Processing of Materials Ministry of Education,Shandong University,Jinan 250061)

机构地区：[1]山东南山铝业股份有限公司,龙口264000 [2]山东大学材料液固结构演变与加工教育部重点实验室,济南250061

出　　处：《机械工程学报》2023年第24期131-139,共9页Journal of Mechanical Engineering

基　　金：山东省重点研发计划(重大科技创新工程)资助项目(2021ZLGX01)。

摘　　要：Al-Zn-Mg-Cu合金广泛应用于航空航天等高端关键构件,然而由于其残余结晶相及晶界元素偏析等缺陷的影响,造成构件的力学性能较差等问题。因此,在变形温度435℃和变形速率0.01 s^(-1)的条件下,对均质后的Al-Zn-Mg-Cu合金方坯进行多向锻造(Multi-directional forging,MDF)试验。通过扫描电子显微镜(Scanning electron microscopy,SEM)、能谱仪(Energy dispersive spectrometer,EDS)和电子背散射衍射(Electron back scatter diffraction,EBSD)等微观表征手段,研究多向锻造道次对该合金晶粒形态、残余结晶相分布和元素偏析的影响规律。结果表明,锻造道次对变形后Al-Zn-Mg-Cu合金残余结晶相的消减效果有较大影响。随着锻造道次的增加,合金中的残余结晶的数量逐渐减少,Cu元素偏析问题得到明显改善。经多向锻造后,方坯芯部区域的微观组织表现为整体晶粒粗大,在大晶粒周围存在大量新生再结晶晶粒,且新生晶粒晶界具有典型的动态再结晶特征,而这种动态再结晶趋势随锻造道次增加其效果更明显。Al-Zn-Mg-Cu alloys are widely used for high-end carrier components in the aerospace industry,however,the mechanical properties of the components are poor due to the influence of defects such as residual crystalline phases and grain boundary element segregation.Therefore,multi-directional forging(MDF)tests are performed on homogenized Al-Zn-Mg-Cu alloy billets at a deformation temperature of 435°C and a deformation rate of 0.01 s^(-1).The effects of multi-directional forging pass on the grain morphology,residual crystalline phase distribution,and elemental segregation during the multi-directional forging process are investigated by scanning electron microscope(SEM),energy dispersive spectroscopy(EDS),and electron backscattered diffraction(EBSD)microscopic characterization.The results show that the number of forging passes has a large effect on the reduction of the residual crystalline phase of Al-Zn-Mg-Cu alloy after deformation.With the increase of forging passes,the number of residual crystallites in the alloy gradually decreases,and the problem of Cu elemental segregation is significantly improved.After multi-directional forging with different forging passes,the core region shows coarser grains in microstructure,but a large number of newly recrystallized grains existed around the large grains,and the grain boundaries of the newly recrystallized grains had typical different continuous dynamic recrystallization characteristics,and this dynamic recrystallization trend was more obvious with the increase of forging passes.

关 键 词：AL-ZN-MG-CU合金 多向锻造 残余结晶相 元素偏析 微观组织 

分 类 号：TB31[一般工业技术—材料科学与工程]