Development of a Scalable Method for the Synthesis of High Quality (Ba,K)-122 Superconducting Powders

Abstract

Iron-based superconducting (IBS) wires fabricated through the powder-in-tube (PIT) method are prospective candidate materials for high magnetic field applications. In order to meet the requirements of such applications, it is important to obtain practical conductors with high transport critical currents at a competitive cost. Among the several IBS families, the (Ba,K)Fe₂As₂ (Ba-122) phase has the best potential to become a cost-effective high-field superconductor. However, two aspects of the fabrication procedure present issues which still hinder the development towards the affirmation of such superconductor in the industrial applications field: on one side the powder purity, especially when developing a route for the fabrication of large amounts, and on the other side the application of techniques scalable to obtain long length conductors with the same transport properties of the short samples. We here focus on an innovative and scalable fabrication process we have developed to fabricate pure Ba_1-xK_xFe₂As₂ powders in batches up to the order of 25 g, a quantity which allows us to fabricate at least 20 meters of monfilamentary conductor.