Novel method of tuning the size of Y₂BaCuO₅ particles and their influence on the physical properties of bulk YBa₂Cu₃O_7-δ superconductor

Abstract

A novel technique for modifying RE2BaCuO5 (211, RE = rare earth elements such as Nd, Sm, Gd, Y etc) particles and tuning their size, distribution and content in REBa2Cu3O7-δ bulk superconductors was demonstrated. Varied ultrasonic power was employed to produce fine-sized, individual, sharp-edged 211 phase particles along with mechanically damaged surfaces. The size and content of the 211 phase of infiltration growth-processed YBa2Cu3O7-δ bulk samples were gradually decreased. The effective grain refinement enhanced the critical current density by a factor of two. A maximum trapped field of 0.48 T at 77 K was obtained for a sample with 20 mm diameter by treating the 211 phase particles for 60 min with 300 W energy.

Superconducting YBCO Foams as Trapped Field Magnets

“…The improvement of the current densities within the foam struts will be the main challenge for the future development of superconducting foam samples, and a key to this will be an improvement of the texture achieved. For this purpose, the recent developments concerning the generic seed crystals [52], the IG-process [31,37], the pre-treatment of the 211 powders [53,54] and chemical doping to improve texture [55,56] will have to be applied to the fabrication of foam samples. Nevertheless, our first results are promising, so thus we may discuss possible applications of the foam samples to set directions and goals for the coming improvements.…”

Effect of Ultra-sonicated Y2BaCuO5 on Top-Seeded Melt Growth YBa2Cu3Oy Bulk Superconductor

“…To refine further and ensure uniform mixing, the precursor mixture of Y123 and Y211 is subjected to automatic grinding for 2-3 h. To avoid any contamination in the powders, we chose high energy ultra-sonication to refine the Y211 particles. The ultrasonic waves increased disorder in the medium and lead to separation and size reduction of the particles [15,16]. In summary, the nature of initial Y211 particles greatly influences properties of bulk YBCO (see in Table 1).…”

“…In our previous work, we tried to synthesize samples by infiltration growth using ultra-sonicated Y211 [15]. There we synthesized bulk with improved properties because of Y211 size reduction.…”

High-energy ultrasonic irradiation effects on the growth and critical current density of top-seeded melt grown single grain YBa2Cu3O7-δ bulk superconductors

“…In this regard, in order to improve the flux pinning of REBCO superconductors, by a team of S. Pavan Kumar Naik et al, for the first time, a novel method of high-energy ultrasonic radiation was employed for pre-treating 211 powders [14][15]. Later this method is applied to other superconductors successfully and improved their performance [16]. In this method, individual 211 particles with sharp edges were produced by high-energy ultrasonic irradiation reducing the micron sized starting powders to ~100 nm size.…”