Event Timeslots (1)

Day 2 – June 21
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Lithium-containing ceramics are one of the tritium breeding concepts to be tested in ITER. Due to the specific needs of a breeder blanket and the wide range of properties offered by the materials considered, no single lithium ceramic has been singled out as the best compromise between physical properties and lithium density. Two main ceramics have been identified as potential lithium sources, however: lithium metatitanate (Li2TiO3) and lithium orthosilicate (Li4SiO4). Conventional high temperature fabrication techniques can lead to lithium loss due to volatilisation, decreasing the lithium density in the final product. Here we apply low temperature fabrication techniques to the formation of dense, lithium-containing ceramics, including the newly developed reactive cold sintering (RCS) method. This novel fabrication method enables the formation of dense pellets at reduced temperatures, addressing lithium volatilisation concerns, and also allows the incorporation of chemically and/or morphologically distinct phases, enhancing control over the composition and microstructure. This has ultimately enabled the formation of composite ceramics more specifically tailored to the needs of a breeder blanket. In this contribution we demonstrate the flexibility of the RCS method which was used to produce dense Li2TiO3 with bi-modal grain size distribution, and a dense Li2TiO3-Li4SiO4 composite material. As well as microstructural data, thermal and mechanical data will be presented and compared to ceramics produced via more conventional techniques. Our results suggest that reactive cold sintering could provide a pathway to produce lithium ceramics with little concern for volatilisation as well as a simpler way to introduce enriching phases and allow for retention of specific morphologies from initial powder to final pellet.