Ultra-High Temperature Ceramics (UHTC) are good candidates to fulfil the harsh requirements of hypersonic applications. For more than a decade, ONERA has been actively involved in several programs to develop such materials for different applications (hypersonic flights, propulsion systems ...). In our laboratories, monolithic and composite materials have been investigated as well as several processing methods. In this paper, we present for example the ZrB 2 -SiC and HfB 2 -SiC compositions with TaSi 2 or Y 2 O 3 additions which have been especially studied in the European Projects ATLLAS and ATLLAS 2. Assessments of several prototypes in realistic environment are also described. Furthermore, based on these material developments, a specific study on the oxidation behaviour of such monoliths from 1200°C to 2400°C with a dedicated test bench using a 2 kW CO 2 laser has been carried out (oxidation under air and water vapour atmospheres). Recently, some work on the manufacturing of Ultra-High Temperature Ceramic Matrix Composites (UHTCMC) has been initiated using slurry infiltration and pyrolysis. The behaviour and properties of these materials are encouraging.

In this paper, a Non Destructive Testing approach by active infrared thermography is used to investigate porosity in oxide/oxide CMC specimens. In this study, an experimental bench is developed using pulsed thermography in reflection or transmission modes coupled with transient heat transfer modelling in order to detect inhomogeneities. Results obtained are discussed and compared to ultrasonic testing which is commonly used in Non Destructive Tests.

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