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Hypersonic airliner would be exposed to temperatures that are beyond the limits of classical aircraft materials. In order to handle this problem the latest developments of new materials and composite structures suitable for high temperature application need to be taken into account. The focus of the European Research program ATLLAS is on advanced light-weight, high-temperature material development strongly linked to a high-speed passenger aircraft design. ATLLAS stands for Aerodynamic and Thermal Load Interactions with Lightweight Advanced Materials for High Speed Flight. The 4.5 years program ATLLAS-II is a logical continuation project built upon the experience and technology development gained within ATLLAS-I. The corresponding work related to combustor structures and material integration deals with the opportunity to investigate at academic level, both in basic and relevant environment, different solutions possibly usable to ensure the long range cruise of a high speed airliner. Different materials (UHTC, CMC, metallic) and different cooling techniques (radiation, convective, transpiration) are studied. Available 2 numerical or semi-empirical tools are used to prepare the test, to design the different architectures. A pin fin experiment allows to better know the pressure drop and the heat transfer for different channel patterns with thermal crystal techniques. The ERBURIG K long duration test facility allows to characterize different ceramic matrix composite uncooled samples to realize, at small scale, a long duration (several hours) investigation of cooled ceramic structure in PTAH-SOCAR technology. A multifunctional metallic transpiration cooled HSS panel using Hollow Spheres Stacking as core material was designed and preliminary tested in cold conditions with GN2 and in hot conditions with infra-red lamps under 1 MW/m² heat flux before successful METHYLE testing in supersonic reacting flow. CMC and UHTC materials are used to design, manufacture and test generic fin injectors usable in high speed combustors. Industrial hypersonic METHYLE test facility is used to test in relevant Mach 6 combustor environment CMC and HSS panel as well as advanced fin injectors. Hot and cold permeability of composites is also documented with GN2 and GH2, taking into account the mechanical stress possible effect. Numerical models are used in accordance with the experiments, some examples are also given in the present paper. NomenclatureC/C-SiC = carbon fibre reinforced silicon carbide CFD = computational fluid dynamics CMC = ceramic matrix composite ERBURIG K = Environmental Relevant Burner Rig -Kerosene HSS = Hollow Spheres Stacking (sandwich) FEM = finite elements (mechanical computational) method GN 2 = gaseous nitrogen METHYLE= French acronym for long duration hypersonic technology test facility O 2 = oxygen SiC/SiCN = silicon carbide fibre reinforced silicon carbonitride TLC = Thermochromic Liquid Crystals UHTC = ultra high temperature ceramics

Hypersonic airliner would be exposed to temperatures that are beyond the limits of classical aircraft materials. In order to handle this problem the latest developments of new materials and composite structures suitable for high temperature application need to be taken into account. The focus of the European Research program ATLLAS is on advanced lightweight , high-temperature material development strongly linked to a high-speed passenger aircraft design. ATLLAS stands for Aerodynamic and Thermal Load Interactions with Lightweight Advanced Materials for High Speed Flight. The 4 years program ATLLAS-II is a logical continuation project built upon the experience and technology development gained within ATLLAS-I. The corresponding work related to combustor structures and material integration deals with the opportunity to investigate at academic level, both in basic and relevant environment, different solutions possibly usable to ensure the long range cruise of a high speed airliner. Different materials (UTHC, CMC, metallic) and different cooling techniques (radiation, convective, transpiration) are studied. Available numerical or semi-empirical tools are used to prepare the test, to design the different architectures. A pin fin experiment allows to better know the pressure drop and the heat transfer for different channel patterns with thermal cristal techniques. The ERBURIG K long 2 duration test facility allow to characterize different ceramic matrix composite uncooled samples and will allow to realize, at small scale, a long duration (several hours) investigation of cooled ceramic structure in PTAH-SOCAR technology. A multifonctionnal metallic transpiration cooled HSS panel using Hollow Spheres Stacking as core material was designed and preliminary tested in cold conditions with GN2 and in hot conditions with infra red lamps under 1 MW/m² heat flux. CMC and UHTC materials are used to design, manufacture and test generic fin injectors usable in high speed combustors. Industrial hypersonic METHYLE test facility is used to test in relevant Mach 6 combustor environment HSS panel as well as advanced fin injectors. Hot and cold permeability of composites is documented with GN2 and GH2. Numerical models are used in accordance with the experiments, some examples are given in the present paper. Nomenclature C/C-SiC = carbon fibre reinforced silicon carbide CFD = computational fluid dynamics CMC = ceramic matrix composite ERBURIG K = Environmental Relevant Burner Rig-Kerosene HSS = Hollow Spheres Stacking (sandwich) GN 2 = gaseous nitrogen METHYLE= French acronym for long duration hypersonic technology test facility O 2 = oxygen SiC/SiCN = silicon carbide fibre reinforced silicon carbonitride TLC = Thermochromic Liquid Crystals UHTC = ultra high temperature ceramic USTUTT/ITLR = University of Stuttgart WHIPOX = wound highly porous oxide

Blanching of copper alloys is a major life-limiting degradation mechanism in rocket combustion chambers. Understanding of this mechanism is key to further improvement of rocket engine performance, so to gain further insight into the mechanism oxidationreduction cycles with a variation of temperature, amount of cycles and reduction atmosphere composition have been used to duplicate the blanching mechanism on sample scale. As part of the evaluation the sample weight and the roughness have been measured in the initial state as well as after testing. Furthermore, scanning electron microscope (SEM) investigations have been conducted to distinguish whether sponge-like blanching structures formed during testing. The roughness measurements showed a smoothing of the surface up to about 600°C, with a maximum at about 500°C. Above these temperatures the roughness increased rapidly. The SEM investigation proved to deliver sponge-like blanching structures, also with a strong dependence on temperature. The experiments proved to give trends on the influence of the individual parameters. Temperature was found to be the principal influencing factor, followed by the duration (amount of oxidation-reduction cycles). The composition of the reduction atmosphere was found to play only a supporting role. The results obtained in this study will be the baseline for further investigations in the newly developed Airbus Group Innovations ERBURIG H test facility.

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