High-entropy(Sm_(0.2)Eu_(0.2)Gd_(0.2)Dy_(0.2)Er_(0.2))_(2)Hf_(2)O_(7) ceramic with superb resistance to radiation-induced amorphization  

作　　者：Jingxin Wu Meng Zhang Zhanqiang Li Minzhong Huang Huiming Xiang Liyan Xue Zhengming Jiang Zhigang Zhao Lianfeng Wei Yong Zheng Fan Yang Guang Ran Yanchun Zhou Heng Chen 

机构地区：[1]School of Rare Earths, University of Science and Technology of China, Hefei 230026, China [2]Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou 341000, China [3]Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China [4]Fujian Province Joint Innovation Key Laboratory of Fuel and Materials in Clean Nuclear Energy System, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China [5]Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou 350108, China [6]Science and Technology on Advanced Functional Composite Laboratory, Aerospace Research Institute of Materials & Processing Technology, Beijing 100076, China [7]The Key Nuclear Fuel and Nuclear Materials Laboratory of China, Nuclear Power Institute of China, Chengdu 610213, China [8]China Rare Earth Group Co., Ltd., Chengdu 610213, China [9]College of Energy, Xiamen University, Xiamen 361102, China [10]School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China

出　　处：《Journal of Materials Science & Technology》2023年第24期1-9,共9页材料科学技术（英文版）

基　　金：supported by the Lingchuang Research Project of China National Nuclear Corporation,the National Key Research and Development Program of China(No.2022YFB3504302);the key core technology research project in Beicang District,Ningbo(Grant No.2021BLG009);the key deployment project of the Chinese Academy of Sciences(Grant No.ZDRW-CN-2021-3);the Fujian Provincial Natural Fund Project(Grant No.2021J05101);the Young Elite Scientists Sponsorship Program by CAST(Grant No.2021QNRC001);the independent deployment project of Ganjiang Innovation Research Institute of Chinese Academy of Sciences(Grant No.E055A002);In addition,thanks for the assistance of Jinchi Huang from the School of Energy,Xiamen University for the ion irradiation experiment.

摘　　要：Nuclear engineering materials are required to possess outstanding extreme environmental tolerance and irradiation resistance.A promising novel pyrochlore-type of(Sm_(0.2)Eu_(0.2)Gd_(0.2)Dy_(0.2)Er_(0.2))2 Hf_(2)O_(7)high-entropy ceramic(HE-RE2 Hf_(2)O_(7))for control rod was prepared by solid-state reaction method.The ion irradiation of HE-RE_(2) Hf_(2)O_(7)with 400 keV Kr+at 400℃was investigated using a 400 kV ion implanter and compared with single-component pyrochlore Gd2 Hf_(2)O_(7)to evaluate the irradiation resistance.For HE-RE2 Hf_(2)O_(7),the phase transition from pyrochlore to defective fluorite is revealed after irradiation at 60 dpa.After irradiation at 120 dpa,it maintained crystalline,which is comparable to Gd2 Hf_(2)O_(7)but superior to the titanate pyrochlores previously studied.Moreover,the lattice expansion of HE-RE2 Hf_(2)O_(7)(_(0.2)2%)is much lower than that of Gd2 Hf_(2)O_(7)(0.62%),indicating excellent irradiation damage resistance.Nanoindentation tests displayed an irradiation-induced increase in hardness and a decrease in elastic modulus by about 2.6%.Irradiation-induced segregation of elements is observed on the surface of irradiated samples.In addition,HE-RE2 Hf_(2)O_(7)demonstrates a more sluggish grain growth rate than Gd2 Hf_(2)O_(7)at 1200℃,suggesting better high-temperature stability.The linear thermal expansion coefficient of HE-RE2 Hf_(2)O_(7)is 10.7×10-6 K-1 at 298–1273 K.In general,it provides a new strategy for the design of the next advanced nuclear engineering materials.

关 键 词：High-entropy ceramic Rare earth hafnate Ion irradiation Amorphization resistance High temperature stability Nuclear safety 

分 类 号：TK471[动力工程及工程热物理—动力机械及工程] TG174.4[金属学及工艺—金属表面处理]