Skip to Main content Skip to Navigation
Theses

Endommagement et microfissuration d’un composite à matrice céramique tissé 3D : approchemulti-échelle et évaluation ultrasonore

Abstract : The non-linear mechanical behaviour of CMC involves the initiation and growth of micro-cracks. Ata macroscopic scale, mechanisms of damage can be associated with changes in the stiffness tensor components.By using an ultrasonic device coupled with a tensile machine, a spectro-interferometry methodallows the characterisation of materials during their damaging and thus, the measurement of the state ofmaterial cracking. Ultrasonic test results have yielded a typical behaviour of the 3D SiC/SiC composite. Twoarrays of multi-scale cracks are detected: i) crack perpendicular to the load, i.e., the transverse cracking, ii)debonding on interfaces yarn / matrix or fibre / matrix. The simultaneous use of ultrasonic characterisationresults and micrographic observations under load lead to make assumptions about the kinetics of crackingof these materials: i) transverse matrix cracking between yarns, ii) superimposed on the transverse crackingof transversal yarns, iii) when those both arrays of cracking saturate, transverse cracking reaches the longitudinalyarns. This microscopic cracking array is coupled to matrix/fibre debonding. The micrographicobservations made during a tensile test have been used to estimate the density of transverse cracking versusthe applied stress. The lengths of the decohesion are not measured but can be estimated by comparisonwith amulti-scale modelling.
Complete list of metadata

Cited literature [116 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00959370
Contributor : ABES STAR :  Contact
Submitted on : Friday, March 14, 2014 - 12:18:04 PM
Last modification on : Friday, August 5, 2022 - 2:54:00 PM
Long-term archiving on: : Saturday, June 14, 2014 - 11:25:58 AM

File

GRIPPON_EDITH_2013_CORR.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00959370, version 1

Citation

Edith Grippon. Endommagement et microfissuration d’un composite à matrice céramique tissé 3D : approchemulti-échelle et évaluation ultrasonore. Autre [cond-mat.other]. Université Sciences et Technologies - Bordeaux I, 2013. Français. ⟨NNT : 2013BOR14908⟩. ⟨tel-00959370⟩

Share

Metrics

Record views

336

Files downloads

1088