Characterization of Freeze-Dried Boron Nanopowders and Parameter Optimization in Ex Situ MgB2 Wire Production

This article reports a study to identify optimal synthesis parameters for a pure boron precursor prepared following a patented process developed at CNR-SPIN laboratories, performed in the framework of a collaboration between CNR-SPIN and CERN. Boron is a precursor that plays a crucial role in the MgB2wire manufacturing, as a consequence, the synthesis parameters of the superconducting phase have been investigated. In this article, we report results for MgB2samples synthesized at 870 °C for 17nbsp;h under Ar/5% H2flow and 760 °C for 0.2 h. Magnesiothermic amorphous nanoboron (MANB) and commercial boron nanopowders (purchased from Pavezyum) have been compared in terms of morphological features. MgB2derived from both sources has been characterized and the superconductive properties in the wire form have been compared. Results demonstrate that the MANB performance is comparable with the nanoboron obtained via gas synthesis