Simulated UO2 fuel containing CsI by spark plasma sintering

Herein, an innovative preparation procedure has been deployed enabling, for the first time, the incorporation of volatile fission product simulant into highly dense nuclear fuel pellets. Highly volatile fission products were embedded in a dense UO2 matrix in the form of CsI by simply mixing starting materials and consolidation in a Spark Plasma Sintering step at 1000 degrees C with a 5 min dwell time. CsI particles were evenly distributed throughout the pellet and were located at the grain boundaries. The sintering rate is dependent on the O/U ratio of the powder. Addition of CsI also acts as a sintering aid, reducing the temperature of maximum densification. (C) 2015 The Authors. Published by Elsevier B.V.