| Title |
Parameters to Affect the Cirtical Characteristics of YBaCuO Bulk Prepared by MPMG |
| Authors |
강형곤(Gang, Hyeong-Gon) ; 임성훈(Im, Seong-Hun) ; 박성진(Park, Seong-Jin) ; 한병성(Han, Byeong-Seong) |
| Keywords |
서냉시간 ; 유지시간 ; 자화 ; 고온상 ; 저온상 MPMG(Melt Powdered Melt Growth) ; slow cooling time ; holding time ; magnetization ; YBa_2Cu_3O_7 ; Y_ 2BaCuO_5 |
| Abstract |
This paper shows the parameters to affect the critical characteristic of YBaCuO superconducting bulk fabricated by MPMG (Melt Powdered Melt Growth)process. In order to investigate proper processing variables, the effect of the holding time at the melting temperature and that of the slow cooling time in O_2 ambient on the J_c were experimented. And then with the above obtained heat treatment conditions, the effects of addition of Y_2BaCuO_5 and Ag on the J_c were also investigated. A proper slow cooling time yields phase transformation from Tetragonal (YBa_2Cu_3O_6) to Orthorhombic (YBa_2Cu_3O_7) during an annealing time in O_2. Ag addition plays a role in increasing the T_c and the J_c, but the magnetization decreases. The J_c and the magnetization increase with addition of Y211. J_c of the sample added Ag 10wt% is superiorover 3000 G. Proper holding time, slow cooling time and amount of impurity addition are important parameters in fabricating the YBaCuO bulk by MPMG process with high J_c |