SOLUTION SPINNING OF HIGH-TC OXIDE SUPERCONDUCTING FILAMENT - PART VIII - THE EFFECT OF DEGREE OF SAPONIFICATION OF POLY(VINYL ALCOHOL) ON THE CRITICAL-CURRENT DENSITY OF YBA2CU3OX SUPERCONDUCTING FILAMENT

The precursor YBa2Cu3Ox (Y-123) filaments were prepared by solution sp inning through aqueous poly( vinyl alcohol) (PVA) solution containing mixed Y, Ba and Cu acetates. The as-drawn filaments were heated to rem ove volatile components and to generate a superconducting phase. The e ffect of degree of saponification (DS) of PVA in the precursor filamen t on the critical current density, J(c), for the heated filaments was studied. The precursor filaments were successfully prepared using PVA with DSs ranging from 65 to 81 mol%. The liquid-phase sintering throug hout the filament occurred for the filament spun from PVA solution wit h a DS of 71 mol% and sintered at 920 degrees C for 15 min. The filame nts were partially melted to enhance J(c). The minimum was observed fo r the filament with J(c) a DS of 67 mol%, and the highest J(c) of 3.5 x 10(4) A cm(-2) at 77 K and 0 T was achieved for the filament with a DS of 81 mol%. A configuration of PVA in the precursor filament affect s the superconductivity of the heated filament.