The upper critical field in micro-SiC dopedMgB2 fabricated by a two-step reaction method

Abstract

Low cost micro-SiC doped MgB2 bulk samples were fabricated by a two-step reaction method. Thephase compositions and microstructure of the micro-SiC dopedMgB2 bulk samples were analysed by using x-ray diffraction and a scanningelectron microscope (SEM), respectively. The SEM results indicate that theporosity of the sample produced by the two-step reaction clearly decreases.Hc2 for the micro-SiCdoped MgB2 reached11 T at 20 K. And Jc is 5.6 × 104 A cm−2 at 20 K and 1 T. These results indicate that the two-step reaction method can effectivelyimprove the reactivity of micro-SiC, and significantly improve the upper critical field ofMgB2.