Promising critical current density in the Chevrel phase superconducting wires

Chevrel phase wires with high quality powder were made under very careful conditions. Small coils of about 1 m wire length, treated under hot isostatic pressing conditions, were measured in a magnetic field up to 15 T. We have obtained a critical current density of 5.0 x 10(8) A/m(2) at 15 T and 4.2 K. This represents an improvement of 35% with respect to the best reported results to date. We show that these J(c) values are still extrinsically limited by a few defects responsible for the thermal quench of the coils. When it was possible to localise the defects, holes in the anit-diffusion barrier were observed.