Application of Mechanical Activation for Production of Zirconate Pyrochlore Ceramic Containing Simulated Rare-Earth: Actinide Fraction of HLW

Samples of zirconate pyrochlore ceramic (Ln)₂(Zr,U)₂O₇ (Ln - lanthanides) containing simulated REE-An fraction of HLW were synthesized by conventional cold pressing of oxide mixtures in pellets under pressure of 200 MPa and sintering of pellets at 1550 °C for 24 hours and using preliminary mechanical activation of oxide powders for 5 or 10 min with a reduced sintering time for 6 hours. One more sample was produced by plasma melting. All the ceramic samples sintered at 1550 °C were monolithic and dense with high mechanically activated powders had higher chemical durability and mechanical properties.