Plastic Forming of High‐T_cYBa₂Cu₃O_7−x Bulk Superconductors

Abstract

The large bulk high-T c YBa 2 Cu 3 O 7Àx (YBCO) superconductor samples were prepared by plastic-forming method. We examined the effects of the solvent and the crystallinity of YBCO powder on the composition, crystallinity, and superconducting properties of YBCO sheet samples (sample size: 50 mm 3 50 mm 3 3 mm). By changing the solvent from water to turpentine oil, the leaching of Ba 2+ ions from YBa 2 Cu 3 (OH) y multimetallic hydroxide particles used as an inorganic binder and the YBCO powder were reduced. This results in the composition of the grain boundaries of fired YBCO sheet samples to be the same as the composition of YBa 2 Cu 3 (OH) y multimetallic hydroxide particles. Changing nondoped YBCO powder prepared by sintering to 5 wt% Pt-doped YBCO powder prepared by melt texturing, J c value of YBCO sheet samples changed from about 700 to 6,106 A/cm 2 at 77 K.

Efficient Fabrication of Ultralight YBa2Cu3O7−x Superconductors with Programmable Shape and Structure

“…where ΔM is the width of the magnetization hysteresis loop (emu cm −3 ), and a and b (a > b) are the cross-sectional dimensions of the sample perpendicular to the field. As shown in Figure 4c, the J c (H) exponentially decreased with increasing magnetic field at different temperatures (10,35,55, and 77 K).…”

“…[ 9 ] Therefore, significant efforts have been devoted to the development of one‐step methods for tailoring YBCO structures to obviate the need of secondary processing. YBCO samples with different geometries have been manufactured by plastic forming, [ 10 ] slip casting, [ 11 ] extrusion free‐forming, [ 12 ] and injection molding. [ 13 ] However, these state‐of‐the‐art methods have poor commercial competitiveness because of their complex and time‐consuming operation and low refinement on multiscale structures.…”

Synthesis and characterization of Ca3Co4O9 thermoelectric ceramics using the slurry sintering method

“…In our previous research, we explored synthesis and characteristics of CdTe, Bi 2 Te 3 and other compound semiconductors for energy conversion as well as YBa 2 Cu 3 O 7 and other oxide superconductors using electrodeposition, sol‐gel method, slurry sintering, and other techniques.…”