(Bi，Pb)-2223带材超导芯部的熔化分解及其再形成

The decomposition and reformation of superconducting core in the(Bi,Pb)-2223 tape

分析了(Bi,Pb)-2223高温超导材料传导性能进一步提高的影响因素,阐述了熔化处理对改善(Bi.Pb)-2223带材芯部微观结构的优越性.结果表明,传统的(Bi,Pb)-2223相非平衡成相机制严重制约了熔化处理工艺的效果,确立了(Bi,Pb)- 2223相从液相中可逆再形成的可能性,研究了不同条件下(Bi,Pb)-2223相熔化分解-再形成的相演变特征.在适当温度下,(Bi,Pb)-2223相部分熔化分解,生成一种类似于2212化学计量比的液相及碱土铜酸盐2:1-AEC和14:24-AEC,对于其与液相或熔体之间平衡转变关系的建立极为重要.

The melting and recrystallization behaviors of （Bi,Pb）-2223 core in the Ag-sheathed tape have been investigated via static melting experiment under different conditions. The feasibility of the （Bi,Pb）-2223 reformation directly from the melt has been investigated. It is shown that a partial melting of high-Tc core at some temperature in an appreciate range, which bring a 2212-Iike melt and alkaline earth cuprates （AEC）, especially 14：24-AEC and 2：1-AEC, is very important for establishing the equilibrium transformation between （Bi,Pb）-2223 and the melt.