With two phi 26 mm YBCO bulks, a superconducting permanent magnet of 7.09 T
with low creep was achieved at 29.8 K. Cracks occurred when the activating
field of 10 T was applied, showing that the critical field is limited by m
aterial strength. With one YBCO bulk, 4.38 T (4.2 K) and 2.71 T (50 IC) was
achieved. (C) 2000 Elsevier Science B.V. All rights reserved.