The upper critical field in micro-SiC doped MgB₂ fabricated by a two-step reaction method

Low cost micro-SiC doped MgB₂ bulk samples were fabricated by a two-step reaction method. The phase compositions and microstructure of the micro-SiC doped MgB₂ bulk samples were analysed by using x-ray diffraction and a scanning electron microscope (SEM), respectively. The SEM results indicate that the porosity of the sample produced by the two-step reaction clearly decreases. H_c2 for the micro-SiC doped MgB ₂ reached 11T at 20K. And J_c is 5.6 × 10 ⁴Acm^-2 at 20K and 1T. These results indicate that the two-step reaction method can effectively improve the reactivity of micro-SiC, and significantly improve the upper critical field of MgB₂.