Pinning properties in pure and SiC doped MgB2 bulk obtained by reactive Mg liquid infiltration technique

Abstract

The effects of SiC additions on pinning properties of MgB2 bulk samples, obtained by reactive Mg liquid infiltration (RLI) in Boron powders preforms have been analysed by means of electric transport measurements at different applied magnetic fields. For doped and undoped systems the E vs. J characteristics as well as the pinning energy dependence as a function of the current density has been evaluated and analysed in the framework of thermal creep models. The doping-induced pinning centres, very effective in the pinning property improvements, turned out to be of similar nature than those of the undoped sample and can be mostly attributed to SiC reactive insertions inside the MgB2 grains with an increase of lattice disorder induced by the relative reaction products. © 2007 Elsevier B.V. All rights reserved.