The effect of different dwell times in the ball milling process on the superconducting properties of Bi1.8Sr2Ca1.1Cu2.1Oy (Bi-2212) ceramics

In this paper, the effect of the applied different dwell times (1, 4, and 8 h) during ball-milling on the basic properties of Bi-2212 ceramics has been investigated. Bi1.8Sr2Ca1.1Cu2.1Oy was selected as the initial composition to obtain the high amount of Bi-2212 phase. All samples have been prepared by the conventional solid state reaction method. It has been observed that increasing dwell time negatively affected the superconducting properties of Bi-2212 samples because of the formation of structures with weak grain links. The magnetic properties of samples were determined from the magnetic hysteresis loops (M-H) between 2 T at 10 K, showing that the width of M-H loops has been significantly decreased with increasing dwell time. In addition, the magnetic critical current densities (J(c)) of the samples were calculated from their magnetic hysteresis loops using the Bean's model. The highest value of J(c) has been observed in the sample exposed to dwell time of 1 h.