ABSTRACT
Progress in the mass production of newly developed bulk (Gd0.33Y0.13Er0.53)Ba2Cu3Oy "(Gd,Y,Er)123" and MgB2 systems is presented. Two batches of (Gd,Y,Er)123 pellets of 20 mm diameter and 7 mm thick were prepared in air by an infiltration growth "IG" process. Trapped field distribution profiles of fully grown bulk samples clearly showed that all samples were single-grain and the trapped field values were more than 0.5 T at 77 K, 1.3 mm above top surface. The best bulk exhibited the trapped field value of 0.63 T at 77 K. Ultra-sonication technique was employed for refining precursors of both (Gd,Y,Er)211 and boron. TEM studies revealed that boron powder subjected to ultrasonication was refined up to nanoscale. The micron-sized particles were reduced to nanoscale, which led to improvement of critical current by up to 36% in bulk MgB2 at 20 K and self-field. This progress in fabrication of high-performance LREBa2Cu3Oy and MgB2 superconducting bulks further promotes commercialization of superconductors' production as a mode of sustainable technology.
