Thermal-driven gigantic enhancement in critical current density of high-entropy alloy superconductors  

作　　者：Jihyun Kim Soon-Gil Jung Yoonseok Han Jin Hee Kim Jong-Soo Rhyee Sunmog Yeo Tuson Park 

机构地区：[1]Department of Physics,Sungkyunkwan University,Suwon 16419,Republic of Korea [2]Department of Physics Education,Sunchon National University,Suncheon 57922,Republic of Korea [3]Department of Applied Physics and Institute of Natural Sciences,Integrated Education Institute for Frontier Science and Technology(BK 21 Four),Kyung Hee University,Yongin,17104,Republic of Korea [4]Korea Multi-purpose Accelerator Complex,Korea Atomic Energy Research Institute,Gyeongju,Gyeongbuk,38180,Republic of Korea [5]Center for Quantum Materials and Superconductivity(CQMS),Sungkyunkwan University,Suwon 16419,Republic of Korea

出　　处：《Journal of Materials Science & Technology》2024年第22期60-67,共8页材料科学技术（英文版）

基　　金：supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MIST)(Nos.2021R1A2C2010925,RS-2023-00240326,and RS-2023-00220471);Basic Science Research Program through the NRF of Korea funded by the Ministry of Education(Nos.NRF-2019R1F1A1055284 and NRF-2021R1I1A1A01043885).

摘　　要：The high-entropy alloy(HEA)superconductor,Ta_(1/6)Nb_(2/6)Hf_(1/6)Zr_(1/6)Ti_(1/6)(Ta-Nb-Hf-Zr-Ti),is systematically studied to examine changes in superconducting critical properties,critical temperature(T_(c)),critical cur-rent density(J_(c)),and upper critical field(H_(c2)),concerning thermal treatment conditions.Annealing condi-tion affects Jc more significantly than T_(c)and H_(c2),with a large improvement of flux pinning force density(F_(p)).The Jc of bare sample is reduced to 10 A cm^(-2)at an applied magnetic field of approximately 1.5 T,whereas the sample annealed at 550℃for 12 h exhibits J_(c)>100 kA cm^(-2)up to around 4 T.Furthermore,the Vickers hardness(HVIT)of the Ta-Nb-Hf-Zr-Ti HEA superconductor notably increases from∼384 to 528 HVIT following a 24-h annealing at 500℃.These results demonstrate that thermal annealing is a powerful process to optimize both the superconducting and mechanical properties of high-entropy alloy superconductors.

关 键 词：High-entropy alloy superconductor Ta-Nb-Hf-Zr-Ti ANNEALING Critical current density HARDNESS 

分 类 号：TG139[一般工业技术—材料科学与工程]