Elsevier, Procedia Engineering, (10), p. 1883-1888, 2011
DOI: 10.1016/j.proeng.2011.04.313
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Thepresentworkinvestigatesthemechanicalresponseofapolycrystallineaggregatebythecombineduseof3DX-raydiffractioncontrasttomography(DCT)experimentandthefastFouriertransform(FFT)numericalhomogenisationscheme.Themicrostructureofarecrystal-lizedsampleof304LausteniticsteelhasbeencharacterizedwiththeDCTtechniqueatESRF(ID11beamline)whichallowstohaveaccesstothespatialdistributionandtheindividualshapeoftheconstituentgrainstogetherwiththeircrystallineorientati.Toestimatethemechanicalbehaviourofsuchrealpolycrystallinemicrostructure,themostwidelyusedapproachisbasedonthefiniteelementtechniquewhichimpliesatediousandcomplextaskofmeshing.Tocircum-ventthisdifficulty,anattractiveapproachistheFFT-basednumericalschemewhichallowstousethedigitalimageofthemicrostructureasadirectinputtocomputethemechanicalresponseofaheterogenesmaterial.Theefficiencyofthismethodcombinedwithexperimentaltomographicdataisemphasizedandtheelasticandelastic-plasticbehaviorofthepolycrystallinesampleisinvestigated.Comparisonsaremadewithestimatesdeliveredbytheself-consistentapproach,thatrelyonpartialinformationonthemicrostructure,andfirstorderbounds