A STATISTICAL PLACKETT-BURMAN DESIGN OF THE THERMAL-PROCESS IN THE SYNTHESIS OF THE BI-2223 HTSC

In this study, the most significant parameters in the thermal process for the preparation of high-quality Bi-2223 HTSCs are determined using a statistical Plackett-Burman screening design. This enabled us to ob tain a quick and objective evaluation, where the significant parameter s could be unambiguously defined, accounting for interactions with oth er parameters. Using the optimal conditions of the thermal process and starting from a spray dried nitrate solution with nominal composition Bi:Pb:Sr:Ca:Cu = 1.5:0.5:2:3:4, a more than 96% pure Bi-2223 phase (r elative to the Bi-2212 phase) could be synthesized in a minimal therma l process of 5 h calcination at 650 degrees C and 60 h sintering at 85 5 degrees C.