喷射沉积态Al-Zn-Mg-Cu合金的高温变形行为及组织演变  

Deformation Characteristics and Microstructure Evolution of Spray-Deposited Al-Zn-Mg-Cu Alloy

作　　者：罗锐[1] 曹赟 邱宇[2,3] 袁志钟 李绍伟[1] 程晓农 Luo Rui;Cao Yun;Qiu Yu;Yuan Zhizhong;Li Shaowei;Cheng Xiaonong(School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,China;China FSW Center,Beijing Aeronautical Manufacturing Technology Research Institute,Beijing 100024,China;AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]北京赛福斯特技术有限公司中国搅拌摩擦焊中心,北京100024 [3]中国航空制造技术研究院,北京100024

出　　处：《稀有金属》2022年第2期144-152,共9页Chinese Journal of Rare Metals

基　　金：江苏省高等学校自然科学研究面上项目(19KJB430001);江苏省重点研发计划项目(产业前瞻与共性关键技术)(BE2017127);中国博士后科学基金项目(2019M661738);国家自然科学基金项目(51771082)资助。

摘　　要：利用物理模拟技术对喷射沉积态Al-Zn-Mg-Cu合金在高温变形参数(350~450℃,0.001~20.000 s^(-1))下的热变形特征进行了研究。结合金相显微镜(OM)、扫描电镜(SEM)以及透射电镜(TEM)等微观多种表征手段系统分析了材料在变形过程中的微观组织演化过程,尤其是其第二相的演变规律。实验结果表明:变形温度和应变速率的变化对该合金所受的变形抗力影响显著,其抗力值随变形温度的上升或应变速率的下降而下降,并呈现出动态回复(DRV)的特征;基于动态材料模型理论(DMM)构筑了Al-Zn-Mg-Cu合金的热加工图,并结合不同变形区域条件下的微观组织进行验证。明确了该合金的流变失稳区域,主要位于高温(>420℃)高应变速率(>1.000 s^(-1))附近,并随应变的增加失稳区域有所扩大。合金的热加工窗口为390~450℃,0.001 s^(-1);原始态合金中存在着100 nm左右的η-MgZn_(2)相,随着变形温度的升高,η-MgZn_(2)相粗化趋势显著,形变诱导析出了大量纳米级的共格Al_(3)Zr相,有效起到钉扎位错迁移的作用。7055 aluminum alloy is a typical kind of Al-Zn-Mg-Cu alloy,which is widely used in the high-end equipment manufacturing fields such as the aerospace industry and defense industry.7055 aluminum alloy possesses a series of excellent properties,such as high specific strength,specific stiffness,toughness and great corrosion resistance,which renders itself a title of the best comprehensive property aluminum alloy.In the manufacturing process of such aluminum alloy,hot forging,hot rolling and other hot processing can enhance the material properties through deformation strengthening,recrystallization and other behaviors.However,the determination of improper hot processing parameters can easily cause the material to fail,generating cracks,poles and adiabatic shear band.In addition,such kinds of aluminum alloys possess abundant second phases,which attributes to the high strength of the alloy.In the process of hot processing,the evolution of the second phase particles will have a potential impact on the subsequent microstructure transformation.As a result,the determination of reasonable hot processing parameters is of paramount importance to improve the material final working and service performance.The aim of this paper is to precisely detect the flow stress behavior of the 7055 Al-Zn-Mg-Cu alloy,determining the best hot deformation domain and investigating the microstructure evolution law of such alloy,especially the evolution of the second phase during hot deformation.Thus,the successful investigation of this paper can be useful to both the industry manufacturing and scientific studies.In this paper,a special kind of Al-Zn-Mg-Cu aluminum alloys with spray forming state was prepared.And a series of experiments were carried out to systematically investigate the high-temperature deformation behavior and microstructure evolution of such Al-Zn-Mg-Cu aluminum alloys.The raw material was machined into a round bar shape with a diameter of 10 mm and a height of 15 mm.The hot compression test was carried out using a Gleeble-3500

关 键 词：喷射成形 AL-ZN-MG-CU合金 热变形 加工图 第二相 

分 类 号：TG146.1[一般工业技术—材料科学与工程]