Microstructure and Superconductive Property of the Extruded MgB2/Al Composite Materials

Abstract

The superconductive MgB2/Al composite material with low and high volume fractions of particles were fabricated by our special 3-dimensional penetration casting (3DPC) method. The composite material showed homogeneous distribution of MgB2 particles in the Al-matrix with neither any aggregation of particles nor defects such as cracks or cavities. The critical temperature of superconducting transition (TC) was obtained via electrical resistivity and magnetization to be about 37 ~ 39K. The Meissner effect was also verified in the liquid He, in which a piece of the composite floated above a permanent magnet. Extruded rod and wire were successfully fabricated and they also showed onset TC of 39 K on their electrical resistivities as the same as the billet sample.