固溶工艺对Mg-7.5Gd-3Y-0.5Zr合金微观组织及动态冲击行为的影响  

Effect of solution process on microstructure and dynamic impact behavior of Mg⁃7.5Gd⁃3Y⁃0.5Zr alloy

作　　者：王树梁 王春光 李爱菊 王雪兆 Wang Shuliang;Wang Chunguang;Li Aiju;Wang Xuezhao(School of Vehicle Engineering,Shandong Transport Vocational College,Weifang Shandong 261206,China;School of Mechanical and Automotive Engineering,Qingdao University of Technology,Qingdao Shandong 266520,China)

机构地区：[1]山东交通职业学院车辆工程学院,山东潍坊261206 [2]青岛理工大学机械与汽车工程学院,山东青岛266520

出　　处：《金属热处理》2024年第4期186-194,共9页Heat Treatment of Metals

摘　　要：通过光学显微镜、扫描电镜及能谱分析得到不同单级和双级固溶工艺下合金的显微组织,并利用分离式霍普金森压杆对合金进行动态冲击试验,研究了固溶工艺对Mg-Gd-Y-Zr合金微观组织及动态冲击行为的影响机理,分析了最优固溶工艺下合金的抗冲击性能。结果表明,合金的最优单级固溶工艺为520℃×6 h,最优双级固溶工艺为350℃×6 h+520℃×1 h。与单级固溶处理相比,双级固溶处理后合金的晶粒尺寸明显降低,富稀土方块粒子成分发生变化,Y含量明显增加,Gd和Y含量接近。单级固溶处理合金在应变速率为3649 s^(-1)时的抗压强度最高,为503 MPa,动态析出粒子及方块状富稀土粒子的协调作用是其保持优异抗冲击性的重要原因;双级固溶处理合金在应变速率为4056 s^(-1)时的抗压强度最高,为534 MPa,较单级固溶处理时的抗冲击性能显著提升,这主要得益于晶粒尺寸减小和富稀土粒子与动态析出粒子的协同作用。In order to investigate the influence mechanism of the solution treatment on microstructure and impact behaviour of Mg⁃Gd⁃Y⁃Zr alloy,the microstructure of the alloy under different single⁃stage and two⁃stage solid solution processes was studied by means of optical microscope(OM),SEM and EDS,and the dynamic impact mechanics of the alloy under optimum single⁃stage and two⁃stage solution treatment were tested by using a split Hopkinson press bar(SHPB).The results show that the optimum single⁃stage solution treatment of the alloy is at 520℃for 6 h,and the optimum two⁃stage solution treatment is at 350℃for 6 h then at 520℃for 1 h.Compared with single⁃stage solution treatment,the grain size of the alloy after double⁃stage solution treatment is significantly reduced,the RE⁃rich square particle phase composition changes,the Y content increases significantly and the Gd and Y contents are close to each other.The maximum compressive strength of the alloy after the optimum single⁃stage solution treatment is 503 MPa at a strain rate of 3649 s^(-1),and the coordinated action of the dynamic precipitated particles and square⁃shaped RE⁃rich particles is an important factor in maintaining its excellent impact resistance.The maximum compressive strength of the alloy after the optimum two⁃stage solution treatment is up to 534 MPa at a strain rate of 4056 s^(-1),which is significantly higher than that after the single⁃stage solution treatment mainly due to the reduced grain size and the synergistic effect of the RE⁃rich particles and dynamic precipitation particles.

关 键 词：固溶工艺 Mg-7.5Gd-3Y-0.5Zr合金 晶粒尺寸 富稀土粒子 动态冲击性能 

分 类 号：TG166.4[金属学及工艺—热处理] TG146.2[金属学及工艺—金属学]