Shear elastic properties of HTSC ceramics in the region of superconducting transition

The shear elastic properties of YBa$_{2}$Cu$_{3}$O$_{7-x}$ high-temperature superconducting (HTSC) ceramics are studied near the superconducting transition at a temperature of 91.3 K and room temperature of 293 K. For the first time, a local increase in shear nonlinear acoustic parameter $N$ in the region of the phase transition temperature was detected. Experimental studies of the linear and nonlinear elastic properties of YBa$_{2}$Cu$_{3}$O$_{7-x}$ HTSC ceramics in the region of the superconducting transition showed that the electronic phase transition has a significant effect on its elastic properties. Based on experimental measurements, linear and nonlinear elastic parameters are determined both at room temperature and in the region of the phase transition.