| Title |
On the Phase Transformation of High Tc Superconductor Y1Ba2Cu3Oy |
| Authors |
차상윤(S . Y . Cha); 허태녕(T . Y . Huh); 장민수(M . S . Jang) |
| Abstract |
The phase transformation of mixture of Y₂O₃, BaCO₃ and CuO powders with mole ratio of 1/2 : 2 : 3 and that of the superconducting Y₁Ba₂Cu₃Oy single phase were investigated by thermal gravimetric and differential thermal analysis between the temperature ranges of 20℃ and 1300℃. Above 1010℃, partial melting and phase decomposition of Y₁Ba₂Cu₃Oy single phase was detected and it was found that the new phases were (Y₂BaCuO_5) and BaCuO₂by SEM -EDX. By considering the change of the thermal expansion coefficient of the superconductor bar with temperature, it was concluded that superconducting Y₁Ba₂Cu₃Oy undergoes phase transformation at 400℃ and 700℃. |