Abstract： The study of "irreversibility line" and magnetization curves of a YBCO superconductor prepared by melt-textured growth method is presented. It is shown that the temperature T* above which the magnetization is reversible can be identified with the temperature above which Jc is negligible, demonstrating the Yeshurun and Malozemoff s theory about "irreversibility line".
1992, Vol. 9 
