SUPERCONDUCTING HYSTERETIC PROPERTIES OF THPT2B2C ALIGNED POWDER AND BULK SAMPLES

Superconducting hysteretic properties of the new ThPt2B2C borocarbide (tetragonal lattice parameters a = 3.822 Angstrom and c = 10.861 Angst rom) with a superconducting transition temperature T-c of 7 K are stud ied using both bulk sample and magnetically aligning fine powder sampl e. Very small superconducting anisotropy was observed for this aligned nonmagnetic powder with magnetic field applied parallel and perpendic ular to the aligned tetragonal basal plane. Contrary to strong flux pi nning in the grain boundaries or impurity sites for bulk sample, very small pinning indicates few pinning centers for aligned but dispersed microcrystalline powder in epoxy.