The relationship between the phase-transition-like anomalies above Tcand superconductivity in YBa2Cu3Ox

Abstract
The phase-transition-like anomalies above Tc were investigated by internal friction, stress-strain curve and lattice parameter measurements. The relationship between the anomalies and superconductivity is studied. The 110-130 K anomaly is found to be closely connected with the 90 K superconducting transition, but no obvious relation was observed for the 210 K anomaly. In addition, a relaxation-type internal friction peak was measured at about 100 K.