STRUCTURE AND SUPERCONDUCTING PROPERTIES OF Y-PD-B-C SYSTEM

A superconducting phase with transition temperature of 23 K found in the Y-Pd-B-C system was identified to have a body-centered tetragonal structure with the lattice parameters of a = 0. 38 nm and c = 1. 08 nm. The phase is of a platelike shape embedded in a matrix of other phases. The composition ratio of the superconducting phase determined using an electron probe X-ray microanalyzer is YPd2B2C1.5, although there may be uncertainty of the C concentration. The observation by high-resolution transmission electron microscopy indicates that the crystal structure is very similar to that reported recently for the superconducting LuNi2B2C intermetallic compound.