Analysis of the damage initiation in a SiC/SiC composite tube from a direct comparison between large-scale numerical simulation and synchrotron X-ray micro-computed tomography

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:161

Article

Chen, Yang^1,2  Gelebart, Lionel¹  Chateau, Camille²  Bornert, Michel²  Sauder, Cedric¹  King, Andrew³ 

[1] Univ Paris Saclay, CEA, DEN, Serv Rech Met Appl, F-91191 Gif Sur Yvette, France

[2] Univ Paris Est, CNRS, ENPC, IFSTTAR,Lab Navier,UMR 8205, F-77455 Marne La Vallee, France

[3] Synchrotron SOLEIL, F-91192 St Aubin, France

关键词: Ceramic matrix composite;    FFT simulation;    Tomography;    In situ tensile test;    Damage initiation;    Porosity effect;   

DOI  :  10.1016/j.ijsolstr.2018.11.009

来源: Elsevier

【 摘 要 】

Damage initiation is an important issue to understand the mechanical behavior of ceramic matrix composites. In the present work, a braided SiC/SiC composite tube was studied by FFT simulation tightly linked with micro-computed tomography (mu CT) observations performed during an in situ uniaxial tensile test, which provide both the real microstructure, with a good description of local microstructural geometries, and location of cracks at the onset of damage. The FFT method was proven applicable to tubular structures and efficient to complete the large-scale simulation on a full resolution mu CT scan (similar to 6.7 billion voxels) within a short time. The edge effect due to the numerical periodic boundary conditions prescribed on the real and not rigorously periodic microstructure was quantified. The obtained stress field was compared to the cracks detected by the in situ mu CT observations of the same composite tube. This one-to-one comparison showed that cracks preferentially initiated at tow interfaces, where sharp edges of macropores are mostly located and generate stress concentrations. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

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