BaCuO_2-YCuO_(2.5)赝二元系相图

PHASE DIAGRAM OF THE PSEUDO-BINARY SYSTEM BaCuO_2-YCuO_(2.5)

闻差热分析和X射线衍射方法研究了BaCuO_2-YCuO_(2.5)赝二元系相平衡关系。体系被Y_2BaCuO_5和CuO之间的二元连线分开,生成了两个新的化合物:YBa_2Cu_3O_(7-δ)和Y_2BaCuO_5,且YBa_2Cu_3O_(7-δ)是由包晶反应形成的,包晶温度为1020℃±3℃,包晶反应为:Y_2BaCuO_5+L(?)YBa_2Cu_2O_(7-δ),存在两个共晶反应:即在925℃±3℃的条件下,Y_(1.6)Ba_()1-4CU_3O_y发生共晶反应: L+Y_2BaCuO_5(?)YBa_2CU_3O_(7-δ)d+CuO+Y_2BaCuO_6 在1050℃±3℃的条件下,Y_(2.4)Ba_(0.6)Cu_3O_y发生共晶反应: L+Y_2O_3(?)Y_2BaCu_6+YCuO_(2.5)

The pseudo-binary system BaCuO_2-YCuO_2.5 is studied by means of DTA and XRD. BaCuO_2-YCuO_2.5 pseudo-binary phase diagram is separated by the binary linking line between Y_2BaCuO_5 and CuO. Two new compounds YBa_2Cu_2 O_(7-δ) and Y_2BaCuO_5 are formed, and YBa_2Cu_3O_(7-δ) is formed by peritectic reaction at 1020±3℃. Two eutectic reactions occur at 925±3℃ and 1050±3℃ respectively in the system, and the eutectic composition contains Y_(1.6) Ba_(1.4)Cu_3O_y and Y_(2.4)Ba_(0.6)Cu_3O_y.