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arXiv · 2304.04021

FIB-SEM investigation and uniaxial compression of flexible graphite

Emanuele Solfiti·Di Wan·Ambra Celotto·Nicola Solieri·Pablo Andreu Munoz·Rui Franqueira Ximenes·Jorge Maestre Heredia·Claudio Leopoldo Torregrosa Martin·Antonio Perillo Marcone Francois-Xavier Nuiry·Antonio Alvaro·Filippo Berto·Marco Calviani
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Abstract

Flexible graphite (FG) with 1 - 1.2 g/cm$^3$ density is employed as beam energy absorber material in the CERN's Large Hadron Collider (LHC) beam dumping system. However, the increase of energy deposited expected for new HL-LHC (High-Luminosity LHC) design demanded for an improvement in reliability and safety of beam dumping devices, and the need for a calibrated material model suitable for high-level FE simulations has been prioritized. This work sets the basic knowledge to develop a material model for FG suitable to this aim. A review of the FG properties available in literature is first given, followed by FIB-SEM (Focused Ion Beam - Scanning Electron Microscopy) microstructure investigation and monotonic and cyclic uniaxial compression tests. Similarities with other well-known groups of materials such as crushable foams, crumpled materials and compacted powders have been discussed. A simple 1D phenomenological model has been used to fit the experimental stress-strain curves and the accuracy of the result supports the assumptions that the graphite-like microstructure and the crumpled meso-structure play the major role under out-of-plane uniaxial compression.

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Emanuele Solfiti, Di Wan, Ambra Celotto, Nicola Solieri, Pablo Andreu Munoz, Rui Franqueira Ximenes, Jorge Maestre Heredia, Claudio Leopoldo Torregrosa Martin, Antonio Perillo Marcone Francois-Xavier Nuiry, Antonio Alvaro, Filippo Berto, Marco Calviani. 2023-04-08. FIB-SEM investigation and uniaxial compression of flexible graphite. https://arxiv.org/abs/2304.04021

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