EFFECT OF MICROCRACKING ON THE MEASURED MODULI OF BULK YBA2CU3OX

Elastic moduli of both as-hot-pressed and oxygenated YBa2Cu3Ox were measured, under isostatic pressures up to 1 GPa, using a combination of strain gage and ultrasonic techniques. Pressurization of the as-hot-pressed samples caused no significant change in moduli; however, pressurization of the oxygenated sample produced a 5-fold increase in bulk modulus. The results show that the significant decreases in moduli between the as-hot-pressed and the oxygenated state were due to extensive microcracking, of an extremely fine nature, that occurred during the oxygenating sequence. © 1990, Materials Research Society. All rights reserved.