Effects of Re Addition into MgB₂ Superconductor

Abstract

Re was added into the MgB₂ superconductor. The Mg, B and Re were sintered at 1173K for 30 minutes under H₂/Ar atmosphere in the electric furnace. The nominal Re_x(MgB₂)_1-x samples were prepared in 0≤x≤0.05. The field and x dependences of the critical current density J_c were analyzed by the extended critical state model. The enhancement of J_c was observed for the x = 0.02 sample. The effective pinning center should be ReB₂ nano-particles on the MgB₂ grain boundaries.