热加工工艺对Nb_(37)Ti_(20)Al_(15)Zr_(15)Hf_(5)Ta_(5)Mo_(2)W_(1)难熔高熵合金组织与性能影响  

Effect of hot working process on microstructure and properties of Nb_(37)Ti_(20)Al_(15)Zr_(15)Hf_5Ta_5Mo_2W_(1) refractory high-entropy alloy

作　　者：邵旭 庞景宇 纪宇 汤广全 刘文强 程陆凡[2] 李文[1,2] Shao Xu;Pang Jingyu;Ji Yu;Tang Guangquan;Liu Wenqiang;Cheng Lufan;Li Wen(School of Materials Science and Engineering,Shenyang Ligong University,Shenyang Liaoning 110159,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang Liaoning 110016,China)

机构地区：[1]沈阳理工大学材料科学与工程学院,辽宁沈阳110159 [2]中国科学院金属研究所师昌绪先进材料创新中心,辽宁沈阳110016

出　　处：《金属热处理》2023年第9期42-47,共6页Heat Treatment of Metals

基　　金：中国科学院(ZDBS-LY-JSC023)。

摘　　要：利用真空电弧熔炼制备了一种低密度Nb_(37)Ti_(20)Al_(15)Zr_(15)Hf_(5)Ta_(5)Mo_(2)W_(1)(at%)难熔高熵合金,并对该合金进行热变形和均匀化及750℃时效30~120 h。通过X射线衍射、扫描电镜、透射电镜、万能力学试验机等测试方法,对难熔高熵合金的铸态结构、时效后的析出行为和力学性能进行研究。结果表明,铸态难熔高熵合金结构为B2相基体+反相畴界。时效后,大量蠕虫状Zr_(5)Al_(3)相在晶内析出,晶界处有棒状Zr_(5)Al_(3)相析出,诱发晶间断裂。在30 h时效后,该合金的压缩屈服强度为1093.8±7.5 MPa。由于晶间开裂和时效后产生的Zr_(5)Al_(3)相之间的相互作用,导致塑性异常,仅为5.8%;60、90、120 h时效后合金的压缩屈服强度均在1300 MPa左右,塑性均在15%左右,具有优异的稳定性且断口主要为晶间断裂。Nb_(37)Ti_(20)Al_(15)Zr_(15)Hf_5Ta_5Mo_2W_1(at%) refractory high-entropy alloy was produced by vacuum arc melting.Then the alloy was hot deformed+homogenized,and aged at 750 ℃ for 30-120 h.The as-cast structure,precipitation behavior and mechanical properties of the refractory high-entropy alloy after aging were studied by means of X-ray diffraction,scanning electron microscope,transmission electron microscope and universal mechanical testing machine.The results show that the structure of the as-cast alloy is composed of B2 matrix and antiphase boundaries.After aging,a large amount of vermicular Zr_5Al_(3) phase are precipitated within the grain,and rod-shaped Zr_5Al_(3) phase are precipitated at the grain boundaries,inducing intergranular fracture.After aging for 30 h,the compressive yield strength of the alloy is 1093.8±7.5 MPa.Due to the interaction between intergranular cracking and Zr_5Al_(3) phase after aging,the compressive plasticity is anomaly only 5.8%.After aging for 60,90,and 120 h,the compressive yield strength of the alloy is about 1300 MPa,and the plasticity is about 15%.It has excellent stability and the fracture is mainly intergranular fracture.

关 键 词：难熔高熵合金 B2相 结构演化 时效 压缩性能 

分 类 号：TG132.32[一般工业技术—材料科学与工程]