The shock compaction effects on the structural and superconducting properti
es of high-T-c YB2C3Oy particles are investigated. YB2C3Oy particles with a
n average size of 960 nm were prepared by the dry-type jet mill. The lattic
e constants of the orthorhombic cell with a = 0.383 nm, b = 0.390 nm and c
= 1.17 nm for as-shocked YB2C3Oy particles are calculated just after the sh
ock compaction under 5.71 GPa. In the measurements of susceptibility by SQU
ID magnetometer, DeltaM is obtained. It is found that DeltaM(0.00232 emu/g)
for as-shocked YB2C3Oy particles after annealing at 870 degreesC for 10 h
is larger than DeltaM(0.00047 emu/g) for as-shocked YB2C3Oy particles, whic
h seems to indicate the new pinning centres created around the grain bounda
ries during annealing. From scanning electron microscopy observations, the
surface of the specimens for as-shocked YB2C3Oy has large grains of 4-15 mu
m in length partly with large growth-steps caused mainly by heats generated
in shock compaction. Also from the section analysis of atomic force micros
cope image, the vertical distance of about 30-80 nm is obtained around the
edge area in annealed YB2C3Oy grains. (C) 2001 Elsevier Science B.V. All ri
ghts reserved.