COPRECIPITATION PROCESS FOR THE PREPARATION OF SUPERCONDUCTIVE BI-SR-CA-CU OXIDES

BiSrCaCu superconducting oxide powders were prepared from an aqueous solution containing Bi, Sr, Ca, and Cu salts and oxalic acid via coprecipitation using triethyl amine as a base. The dried precipitate was found to have a satisfactory stoichiometry and a particle size of 0.3 μm. Subsequent calcination at 800°C for 10 h and sintering at 870°C for 12 h yielded a superconducting phase with Tc above 80 K. This process can be employed for large-scale preparation of BiSrCaCuO superconducting. © 1990.