CONTINUOUS SYNTHESIS OF YBA2CU3O6-EXPLOSION IN A ROTARY KILN(X BY THERMAL)

Continuous synthesis of YBa2Cu3O6+x superconductor was conducted in a rotary kiln. Dense pellets or loose powder of a stoichiometric mixture of copper, barium peroxide, and yttrium oxide were fed into a heated rotary kiln causing ignition on the whole outer surface followed by an inward movement of a combustion front. Following this thermal explosi on, the pellet was post-treated (sintered) at 900 to 985 degrees C as it moved along the kiln, and a product containing about 95 wt% YBa2Cu3 O6+x was obtained. The impact of the thermal-explosion temperature, th e post-treatment temperature, the pellet density, and the total reside nce time in the kiln on the product quality were studied. The best the rmal-explosion temperature was found to be 800 degrees C, the best pos t-treatment temperature was 985 degrees C, and the total residence tim e in the kiln of 100 minutes was sufficient for the pellet to reach eq uilibrium.