Dynamic recrystallization,texture and mechanical properties of high Mg content Al−Mg alloy deformed by high strain rate rolling  

高Mg含量Al−Mg合金高应变速率轧制变形下的动态再结晶、织构和力学性能

作　　者：Xin-yu LI Wei-jun XIA Ji-hua CHEN Hong-ge YAN Zhen-zhen LI Bin SU Min SONG 黎新宇;夏伟军;陈吉华;严红革;李贞贞;苏斌;宋旼(湖南大学材料科学与工程学院,长沙410082;湖南大学湖南省喷射沉积技术与应用重点实验室,长沙410082;中南大学粉末冶金国家重点实验室,长沙410083)

机构地区：[1]College of Materials Science and Engineering,Hunan University,Changsha 410082,China [2]Hunan Provincial Key Laboratory of Spray Deposition Technology&Application,Hunan University,Changsha 410082,China [3]State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2021年第10期2885-2898,共14页中国有色金属学报（英文版）

摘　　要：The Al−Mg alloy with high Mg addition(Al−9.2Mg−0.8Mn−0.2Zr-0.15Ti,in wt.%)was subjected to different passes(1,2 and 4)of high strain rate rolling(HSRR),with the total thickness reduction of 72%,the rolling temperature of 400℃and strain rate of 8.6 s^(−1).The microstructure evolution was studied by optical microscope(OM),scanning electron microscope(SEM),electron backscattered diffraction(EBSD)and transmission electron microscope(TEM).The alloy that undergoes 2 passes of HSRR exhibits an obvious bimodal grain structure,in which the average grain sizes of the fine dynamic recrystallization(DRX)grains and the coarse non-DRX regions are 6.4 and 47.7mm,respectively.The high strength((507±9)MPa)and the large ductility((24.9±1.3)%)are obtained in the alloy containing the bimodal grain distribution.The discontinuous dynamic recrystallization(DDRX)mechanism is the prominent grain refinement mechanism in the alloy subjected to 2 passes of HSRR.对高Mg含量Al−Mg合金(Al−9.2Mg−0.8Mn−0.2Zr−0.15Ti,质量分数,%)进行不同道次(1,2和4)高应变速率轧制变形,终轧变形量、轧制温度和应变速率分别为72%、400℃和8.6 s^(−1)。采用光学显微镜、扫描电镜、电子背散射衍射技术和透射电镜研究合金的组织演变。合金经2道次高应变速率轧制变形后获得明显的双峰组织,其中细小再结晶晶粒和未再结晶组织的平均尺寸分别为6.4和47.7μm。合金具有高的抗拉强度((507±9)MPa)和伸长率((24.9±1.3)%)。在2道次高应变速率轧制变形过程中,晶界非连续动态再结晶为合金主要的再结晶机制。

关 键 词：Al−Mg alloy high strain rate rolling bimodal grain structure dynamic recrystallization 

分 类 号：TG146.21[一般工业技术—材料科学与工程]