JAUFFRES David

Research interest : Mechanics of materials - Discrete simulations - Multi-physics modeling - 3D image-based modeling - Architectured materials - Ceramic materials - Porous materials

My research activities concern the numerical and experimental study of the sintering and the mechanical behavior of ceramic materials, in particular the relation to their microstructure (porous or not). For this purpose, an original modeling based on the discrete elements method has been developed according to two approaches, one adapted to microstructures having a granular character (partially sintered powders) and the other one adapted to continuous media. Beside that, I also work on the modeling of functional properties of these materials, the 3D characterization of their microstructures and their experimental mechanical characterization.

HDR thesis (in french): Céramiques aux échelles de la microstructure et de l'architecture : frittage, propriétés en service et rupture
HDR defense slides (in english)

One slide presentation of my research activities

Publication list : google scholar

Talks : figshare.com

PhD Students
2022 - ... A. Bigeard  "Etude de l’évolution des propriétés mécaniques et de la consolidation d’un réfractaire tempéré en service"
2021 - ... S. Panisset "Optimization of high performance nano-architectured electrode/electrolyte bilayers
for reversible Solid Oxide Cells" (Coll. with M. Burriel / LMGP)
2019 - 2022 B. Paredes-Goyes "Discrete Element Modeling of constrained sintering" (Mathegram ITN)
2018 - 2021 G. Hamelin "Silica aerogel based thermal super-insulation panels: mechanical properties optimization"
2016 - 2020 N. Khamidy "Microstructure and durability of praseodymium-doped lanthanum nickelate for solid oxide cells"
2016 - 2019 K. Radi "Bioinspired materials : Optimization of the mechanical behavior using Discrete Element Method"
2015 - 2018 E. Guesnet - "Modélisation du comportement mécanique et thermique des silices nano-architecturées"
2013 - 2016 O. Celikbilek - "An experimental and numerical approach for tuning the cathode for high performance IT-SOFC"


Recently published work
 

• Grain growth in sintering: A discrete element model on large packings

Evolution of the microstructure during a discrete element simulation of sintering with grain growth. B. Paredes-Goyes et al., Acta Materialia, 218 117182 (2021).
 

• Mechanical properties of milimetric silica aerogel particles produced through evaporative drying: A coupled experimental and discrete element approach

(a) Particle/granule X-Ray tomography before/after compression test. (b) Simulation for coarse and fine discrete elements. G. Hamelin et al., Journal of Non-Crystalline Solids, 560 120727 (2020).
 

• Effect of microstructure heterogeneity on the damage resistance of nacre-like alumina: Insights from image-based discrete simulations

Crack propagation simulations in homogeneous microstructure (M0), moderately heterogeneous microstructure (M1) and highly heterogeneous microstructure (M3). Stress-strain curves and snapshots of the three main events (a) damage initiation, (b) maximum stress and (c) sample failure. K. Radi et al., Scripta Materialia, 191 210-214 (2021).
 

• Why fumed and precipitated silica have different mechanical behavior: Contribution of discrete element simulations

                           
Left: Typical simulation: compaction of a silica powder bed to VIP core density followed by a tensile test. Odoemetric modulus E₀ and strength σ_f are extracted from the simulation to characterize the mechanical behavior of the silica core produced by the compaction stage. Right: Scaling law between oedometric modulus E₀ and relative density d for precipitated (PS) and fumed (FS) silica. From E. Guesnet et al., Journal of Non-Crystalline Solids, 524, 119646 (2019).