Preparation of tritium breeding Li2TiO3 ceramic pebbles via newly developed piezoelectric micro-droplet jetting

Wet methods as an emerging technique for the preparation of millimeter-sized tritium breeding ceramic pebbles, but the imposed air pressure as the driving forces to extrude slurry droplets are fluctuating during the reciprocating extrusion process, which caused a slight inconsistency in pebble sizes. In this study, a piezoelectric micro-droplet jetting approach was proposed by introducing a piezo-driven valve and modifying the slurry barrel mechanism to realize the air pressure invariable. A self-developed piezoelectric micro-droplet jetting device was successfully utilized to prepare Li2TiO3 green pebbles with coefficients of variation being lower than 2.7%. The size of the green pebbles could be precisely controlled in the range of 0.88-1.37 mm by manipulating the nozzle diameter, the air pressure, and the jetting time. The pebbles sintered at 1000 degrees C for 3 h possessed a small grain size of similar to 5.9 mu m, a satisfied relative density of similar to 84.8% T.D., and a high crush load of similar to 25.7 N, implying the prepared pebbles could be used as a promising solid tritium breeding material in fusion reactors. These findings are anticipated to provide new opportunities for the highly efficient preparation of size-controllable tritium breeding ceramic pebbles.