Glass and ceramic nuclear waste forms: The scientific battle

The scientific battle between two major classes of materials as to the best option for immobilization and disposal of high-level nuclear wastes (HLW) has endured since the 1970s. Both glass and ceramic materials afford different characteristics and properties that make them specifically suitable for certain types of radioactive wastes; both material types have been previously selected as preferred solutions for different waste treatment programs. During the 1980s, glass predominated following its selection for US defense wastes, and this choice is reflected in the available industrial waste treatment facilities to treat HLW. France, the United Kingdom, and the United States are each pursuing huge industrial programs of HLW treatment that isolate radioactive elements in glass forms for ultimate geologic disposal. However, several existing legacy wastes and emerging wastes from future nuclear technologies and fuel cycles will require innovative waste forms, including ceramics and glass-ceramics. This article tells the story of the history of ceramic and glass-ceramic waste forms for the immobilization of HLW and their latest developments. It also highlights some of the essential contributions of professor Rod Ewing (1946-2024) in the areas of radiation damage, natural analogues, and nuclear waste forms.