Investigating the microstructure and mechanical behaviour of simulant “lava-like” fuel containing materials from the Chernobyl reactor unit 4 meltdown

Decommissioning of the damaged Chernobyl nuclear reactor Unit 4 is a top priority for global community. Before such operations begin, it crucial to understand behaviour hazardous materials formed during accident. Since those under extreme and mostly unquantified conditions, modelling alone insufficient accurately predict their physical, chemical and, predominantly, mechanical behaviour. Meanwhile, knowledge characteristics materials, as strength, before robotic systems are employed retrieval force expected from them be exerted one key design questions. In this paper we target measurement standard properties accident by testing small-scale, low radioactivity simulants. A combined methodology using Hertzian indentation, synchrotron X-ray tomography digital volume correlation (DVC), was adopted estimate properties. Displacement fields around performed in-situ in synchrotron, were measured analysing tomograms with DVC. The load applied full-field displacement DVC used properties, Young's modulus Poisson's ratio these materials. • “lava-like” fuel-containing material (LFCM) can classified brittle. Porosity varies depending on type LFCM (brown or black). range lavas between 5 GPa 16 GPa. stiffness brown lava almost 2.5 time greater than that black lava.