Effects of C10H8 Doping on Microstructure and Superconductivity of MgB2 Wires

Abstract:

C10H8-doped MgB2 wires were fabricated by in-situ PIT (Powder in Tube) method. The Nb/Cu tube was filled with the uniformly mixed precursor powders of magnesium, boron and C10H8 with the stoichiometry of MgB2+xwt%C10H8 ,where x=0, 2, 5, 8 and drawn to diameter Φ2 mm and Φ1 mm, respectively, and then heat treated in argon atmosphere at three different temperatures (650, 700, 750 ℃) for 2.5 h. The phase formation and microstructures of the samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and so on. It is found that the critical transition temperature (Tc) changes little with increasing of C10H8 doping content, while normal resistance decreases to some degree. At 20, 25 K and in zero external field, the critical current density (Jc) the sample of x=8 achieves 1.1×105 and 3.8×104 A/cm2, respectively, and the Jc of the sample of x=5 reaches 3.1×104 and 1.2×104 A/cm2, respectively.

Key words:C10H8 doping; MgB2 wires; microstructure; superconductivity