Ceramic matrix composites are lightweight materials with excellent mechanical properties at high temperatures, making them promising candidates for various advanced applications.
Two-dimensional (2D) woven oxide/oxide (Ox/Ox) laminates are particularly relevant for moderate thermomechanical loadings, given their moderate cost compared to Sic/Sic materials, for instance.
However, these materials sustain damage even at low load levels. In order to determine a constitutive damage law that can describe the complex loadings encountered in composite structures, it is necessary to have a precise understanding of their mechanical behaviour at the ply level, as well as to make rigorous observations and measurements of their damage mechanisms.
The aim of this study is therefore firstly to establish the damage scenario in Ox/Ox through tensile, torsion and bending tests on different lay-ups at room temperature.
These tests are highly instrumented, using acoustic emission and digital image correlation, and some have been conducted using CT scanning to analyze damage and failure patterns.
Secondly, based on the experimental tests, a damage law was developed and identified at ply scale on 0/90 and -45/45 tensile specimens.
Model predictions were successfully compared with experimental data obtained on another laminate.
To take this further, the model has been extended to predict fatigue lifetime. A proposed incremental damage model can predict damage evolution during fatigue loading, even for multiaxial spectral loadings.
Finally, this unified damage approach, which is relevant for both static and fatigue loadings, has been implemented in a commercial finite element code, associated to an efficient numerical strategy.
It has been successfully applied to different structures, such as unnotched specimens, open-hole plates, and Ox/Ox components subjected to cyclic fatigue loadings, in order to demonstrate its applicability in a design office.
Speaker:
Frédéric LAURIN Senior Research Engineer at ONERA - The French Aerospace Lab
Frédéric LAURIN was graduated (Engineering Diploma) from the Ecole Centrale Marseille (ECM) in 2002 and obtained his PhD in Mechanics from the University of Franche-Comté in 2005. He joined ONERA in 2005 and works as a research scientist in the Materials and Structures Department. He has been the head of the modelling and characterization unit in the Material and Structure department at Onera from 2016 to 2021.
His research interests include the development of damage and failure approaches for composite materials, strength prediction of composite structures through finite element modelling, and experimental studies of the damage and failure mechanisms encountered in such high performance composite materials. His current researches are also dedicated to (i) the strength analysis of large composite structures representative of aeronautical parts both from numerical and experimental point of view, and to (ii) the integration of solid batteries in composite structures to develop multifunctional components. He is author of 150+ scientific articles and communication in conferences, of which more than 40 articles in highly ranked scientific journals. He is involved in many scientific committees of international conferences on composite materials and member of the French Association for Composite Materials (AMAC) and the European Society for Composite Materials (ESCM).
Free admission, open to all members of the university community and the public, subject to availability.
23.07.2026