MAGNETIC AND RADIOFREQUENCY PROPERTIES OF TEXTURED YBACUO SAMPLES IN MAGNETIC-FIELD UP TO 12 T

The results of an investigation of irreversible phenomena in magnetiza tion, magnetostriction and high-frequency absorption of textures YBa2C u3O7-delta superconductors (phase 123) are reported. The magnetization displays a reversible <<training>> effect unlike low-temperature supe rconductors (LTSC) where it is irreversible. The data on hysteresis an isotropy of a giant magnetostriction are considered. The magnetic flux is found to be instable. A new phenomenon (magnetolamination) Is obse rved and its mechanism is treated. The electromagnetic field absorptio n exhibits a <<normal>> hystoresis different from the <<anomalous>> on e typical of the granular weak-coupled environment of HTSC.