LPSO相对Mg-7Gd-5Y-1Nd-x Zn-0.5Zr(x=1,1.5,2)合金热压缩动态再结晶过程的影响  

Dynamic Recrystallization Process of Mg-7Gd-5Y-1Nd-x Zn-0.5Zr(x=1,1.5,2)Alloy During Hot Compression with LPSO

作　　者：庞铮 赵春雷 杜志伟 韩小磊[1,2,4] 车聪 李永军 Pang Zheng;Du Zhiwei;Zhao Chunlei;Han Xiaolei;Che Cong;Li Yongjun(National Center of Analysis and Testing for Nonferrous Metals and Electronic Materials,China GRINM Group Co.,Ltd,Beijing 100088,China;Guobiao(Beijing)Testing&Certification Co.,Ltd.,Beijing 101407,China;Beijing General Research Institute for Nonferrous Metals,Beijing 100088,China;China United Test&Certification Co.,Ltd.,Beijing 101407,China;State Key Laboratory of Nonferrous Metals&Processes,GRIMAT Engineering Institute Co.,Ltd.,Beijing 101407,China)

机构地区：[1]中国有研科技集团有限公司国家有色金属及电子材料分析测试中心,北京100088 [2]国标(北京)检验认证有限公司,北京101407 [3]北京有色金属研究总院,北京100088 [4]国合通用测试评价认证股份公司,北京101407 [5]有研工程技术研究院有限公司有色金属材料制备加工国家重点实验室,北京101407

出　　处：《稀有金属》2023年第8期1059-1069,共11页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51871195,51501015);国家新材料测试评价平台-主中心项目(TC170A5SU-1)资助。

摘　　要：将Mg-7Gd-5Y-1Nd-x Zn-0.5Zr(x=1,1.5,2)铸态合金在510℃下均匀化热处理48 h,随炉冷却至480℃并分别保温0/1/8 h,利用扫描电镜(SEM)探究热处理后的组织形貌;对热处理后的合金样品进行一系列热压缩试验,并使用电子背散射衍射(EBSD)技术对热压缩后合金的动态再结晶情况进行研究。结果表明:炉冷+预析出热处理过程中,晶粒内部有片层状长周期堆垛有序(LPSO)相析出;晶界、晶界块状LPSO相及晶内片层状LPSO相均对动态再结晶的发生有促进作用,但其促进作用依次减弱,形核位置的优先级依次为晶界、块状LPSO相界面、片层状LPSO相界面。晶内片层状LPSO相的存在能够为动态再结晶提供潜在的形核质点,使动态再结晶晶粒能够从原始晶粒内部开始生长。晶内动态再结晶在片层状LPSO相界面处形核并长大,同时片层状LPSO相抑制了动态再结晶晶粒沿垂直片层方向的生长,使其只能在片层中间生长拉长,不再呈现等轴晶状。Magnesium alloy has the advantages of high specific strength and high specific rigidity,and has a wide range of application prospects in the lightweight of aerospace and transportation.Mg alloys containing long period stacking ordered(LPSO)phase has received widespread attention due to its excellent yield strength at room temperature and high temperature,excellent creep resistance,etc.,compared with traditional Mg alloys.In order to further improve the strength and plasticity,magnesium alloys in actual production applications usually undergo plastic processing such as rolling,forging,and extrusion.As far,there is still controversy about the role of LPSO phase in the process of magnesium alloy deformation and its influence mechanism.The influence of LPSO on the dynamic recrystallization behavior of magnesium alloys during deformation also needs further study.Mg-7Gd-5Y-1Nd-xZn-0.5Zr(x=1,1.5,2)alloys were prepared by melted in the resistance furnance and casted.Then the cast alloys were heated as following treatment:first homogenized at 510℃ for 48 h,then furnace cooled to 480℃ and preserved for 0/1/8 h,respectively,which was defined as pre-precipitation treatment.Hot compression test was performed on heat-treated samples,with deformation temperature of 420/450/480℃,strain rate of 0.001/0.01/0.1/1 s-1,and deformation of 50%,to explore the influence of LPSO on the dynamic recrystallization behavior of the deformation process under different deformation temperatures and strain rates.In order to explore the effect of LPSO phase under different deformations,set experiments with different deformations of 20%/35%/50%/65%/80%.The morphology of the sample after heat treatment were observed by using scanning electron microscope(SEM).Dynamic recrystallization behavior of samples after thermal compression deformation was analyzed by using electron backscattered diffraction(EBSD).SEM results showed that the morphology after heat treatment was mainly composed ofα-Mg matrix and bulk LPSO phase on the grain boundary.Besides

关 键 词：稀土镁合金 长周期堆垛有序相(LPSO) 动态再结晶 热压缩 

分 类 号：TG146.22[一般工业技术—材料科学与工程]