Thermal expansion and electric conductivity of some high-temperature superconductor solid solutions of type 123

摘要

The thermal expansion (in air) and electric conductivity (in oxygen, air, and argon) at 293 - 973 K have been studied for some high-temperature superconductor solid solutions: YBa_(2 - x)Sr_xCu_3O_(7 - y), YBa_(2 - x)Ca_xCu_3O_(7 - y), Nd_(1 - x)Sm_xBa_2Cu_3O_(7 - y), Nd_(1 - x)Tm_xBa_2Cu_3O_(7 - y). Two anomalies were observed on the dilatometric curves and on the temperature dependences of electric conductivity for all samples studied, connected with their phase transitions. From the experimental data the linear thermal expansion coefficient as well as the apparent activation energy of electric conductivity of all samples were calculated.