Hot‐Pressed Glass Matrix Composites Containing Pyrochlore Phase Particles for Nuclear Waste Encapsulation

As alternative immobilization materials for Pu‐bearing nuclear waste, lead‐containing glass matrix composites with homogeneously distributed lanthanum zirconate pyrochlore particles (up to 30 % by volume) have been developed. Fabrication by hot pressing at the relatively mild temperature of 610 °C leaves the pyrochlore structure of the La zirconate unchanged, which is crucial for the containment of radioactive nuclei. The Figure, an SEM image of a polished sample with 30 % La₂Zr₂O₇, demonstrates the homogeneous particle distribution and absence of pores.