Optimization of calcination conditions on the Bi-2223 kinetic formation and grain size

Abstract

The effects of the calcination conditions (time, temperature, intermediate milling) on the kinetics of formation of Bi-2223 and on the grain size were studied using a powder precursor synthesized by the polymer matrix method. The samples were characterized by XRD and SEM analysis. The grain size and the kinetics of formation of Bi-2223 strongly depend on the calcination conditions and thus on the phase assemblages formed at the end of the calcination that determines the reactivity during sintering. The higher the calcination temperature is the larger the grain size. We have observed that 24 h of calcination at 820 °C without intermediate milling allows one to obtain 79% of Bi-2223 phase in 60 h of sintering at 835 °C.

Solution-based synthesis routes to thermoelectric Bi2Ca2Co1.7Ox

“…4a) and sol-gel (Fig. 4b) precursors posses similar grain sizes, while they are bigger for the samples derived from the polymer solution method, as evidenced previously for other layered ceramics 17,18 (Fig. 4c).…”

Sinter-forging of strongly textured Bi2223 discs with largeJcs: nucleation and growth of Bi2223 from Bi2212 crystallites

“…• C for 24 h [16,17] and ground in an agate mortar. The powder was sieved at different sizes (63, 100, 200 µm), hereafter referred to as powders P63, P100 and P200, respectively.…”

Measurements of ultra-low DC fields by high- T c superconducting cores: The effect of calcination temperature

“…It is well known that the higher the calcination temperature the larger the grain sizes [14]. Consequently, the density of weak links becomes low and the critical current density becomes larger.…”