NbC沉淀强化FeCoNiCrMn高熵合金的高温力学性能  

High-temperature Mechanical Behavior of NbC Precipitation Strengthened NiCoFe⁃CrMn High Entropy Alloy

作　　者：刘辉[1] 施洋 卢大海 高妞 刘鑫旺[1] 王凯[2] 邹佳鹏 LIU Hui;SHI Yang;LU Dahai;GAO Niu;LIU Xinwang;WANG Kai;ZOU Jiapeng(State Key Laboratory of Material Forming and Die Technology,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074;High Temperature Materials Research Institute,Central Iron&Steel Research Institute,Beijing 100081)

机构地区：[1]华中科技大学材料科学与工程学院,材料成形与模具技术全国重点实验室,武汉430074 [2]钢铁研究总院高温材料研究所,北京100081

出　　处：《特种铸造及有色合金》2024年第11期1575-1579,共5页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(52071088)。

摘　　要：设计了一种NbC沉淀相强化NiCoFeCrMn高熵合金,在冷轧和再结晶后,退火态(NiCoFeCrMn)_(98.4)Nb_(0.8)C_(0.8)高熵合金基体呈均匀的等轴晶组织,合金内形成了弥散分布的近球形NbC析出相。该合金在873 K下保持了425 MPa的屈服强度以及50.5%的伸长率,与基体合金相比,屈服强度提高了77%,伸长率几乎没有损失。此外,该合金在673~1073 K呈现出锯齿流变特征,这主要是Nb与C元素的掺杂引起合金较大的晶格畸变以及NbC颗粒的析出导致的。A NbC precipitation strengthened NiCoFeCrMn HEA was designed.After cold rolling and recrystallization,as-annealed(NiCoFeCrMn)_(98.4)Nb_(0.8)C_(0.8)HEA exhibits uniform equiaxed grain structure,and a dispersed nearspherical NbC phase was formed.The alloy maintains a yield strength of 425 MPa and a fracture elongation of 50.5%at 873 K.Compared with the matrix alloy,the yield strength is increased by 77%,and the elongation is almost unchanged.In addition,the HEA exhibits serrated flow characteristics at 673~1073 K,which is mainly attributed to the large lattice distortion of alloy caused by doping of Nb and C elements and precipitation of NbC particles.

关 键 词：高熵合金 微观组织 第二相强化 锯齿流变 

分 类 号：TG139[一般工业技术—材料科学与工程] TG113.25[金属学及工艺—合金]