Effect of Boron Particle Size on the Formation and Superconductivity of MgB₂

Abstract

MgB₂ superconductors were prepared by sintering of a mixture of Mg powder and born powder with different particle sizes at 1073K for 12h. The single MgB₂ was obtained at particle sizes below 20μm and showed a superconducting onset temperature of 38K and zero resistance temperature of 36K. The amorphous boron with particle sizes below 1μm makes it easier to form a MgB₂. The single MgB₂ was obtained by sintering at 1073K for 1h. Even by the sintering at a temperature as low as 873 K, the MgB₂ with a zero resistance temperature of 36K was obtained.