Homogeneity of SiC distribution in IMD MgB2 wires

Abstract

In this work, MgB2 wires with different SiC doping levels were processed using the internal Mg diffusion method and the evolving MgB2 reaction layers were thoroughly analyzed with an electron probe micro-analyzer. It was also shown that high performance wire can be obtained by optimizing SiC contents and heat treatment conditions. The SiC dopant is uniformly distributed in the boron matrix at the macroscale. The highest layer J c value of 5 × 104A cm−2 at 4.2 K and 10 T is achieved in the sample with 7 at% SiC doping and sintered at 640 °C for 15 h. This high layer J c is considered to be due to the doping effect as well as uniform dispersion of SiC particles. The SiC distribution homogeneity can be explained by matrix-to-additive particle size ratio.