This paper proposes a simple bonding and measuring technique to realise silica-based chemical composition gratings' (CCGs) high temperature applications on hot structures. We describe a series of experiments on CCGs to measure the thermal and mechanical response characteristics of ultra-high temperature ceramic (UHTC) materials when the maximum temperature is above 1000°C. Response characteristics are obtained at the heating and cooling stages. Results show that the wavelength response of the CCGs bonded on the UHTC plate increases non-linearly with increasing temperatures, but decreases almost linearly with decreasing temperatures. The temperature-dependent strain transfer coefficients are calculated theoretically and experimentally; results show that the values of strain transfer coefficients below 1000°C are significantly affected by the thermal expansion coefficient of the substrate material and the interface. The strain transfer coefficient value tends to vary slowly between 0.616 and 0.626 above 700°C.

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Ceramic Matrix Composites (CMCs) are primary candidates for advanced gas turbine engine application that require intense high temperature tests and validations. Before CMCs used in engine hot sections, a lot of tests need to be done, especially thermal test. A thermal test rig has been set up to simulate the engine turbine thermal environment. Propane gas is used to simulate the practical aviation fuel and compressed air with flow regulator is used as cooling media. The capabilities and limitations of the test facility have been calibrated and discussed in this paper. A CMC turbine vane with internal cooling path was tested on this burning rig. The results showed that the CMC vane could withstand the 1200 ℃ thermal cycling test but the coating was disappeared. It has been proved that such test rig and method could simulate the thermal boundary conditions of turbine vanes and blades.

This paper describes an experimental and signal processing technique to perform high temperature tests on superalloy (INCONEL) and carbon/carbon structures using silica‐based chemical composition gratings (CCGs). The results obtained from applying this technique at 940°C in superalloys and 950°C for carbon/carbon (C/C) composites are benchmarked against data obtained from four different methods. The results show that the wavelength responses of the CCGs bonded on the superalloy and on the C/C plate increase nonlinearly with increasing temperatures. The temperature‐dependent strain transfer coefficients recorded during the superalloy tests show quite stable results below 600 °C and tend to slightly decrease thereafter. The values of the strain transfer coefficients below 1000 °C are significantly affected by the thermal expansion coefficient of the substrate material and the interface. We demonstrate that the strain transfer coefficient calculation method used in this paper is not suitable for low and/or negative expansion material. The results of the relative errors show that the CCGs‐F method based on the quadratic dependence of the wavelength shift versus the temperature appears to be the best to estimate the mechanical strains within the interval of temperatures considered and the measurement accuracy. The relative errors measured between 200 °C and 1000 °C are less than 5%.

Solidly mounted film bulk acoustic resonator (SMR-FBAR) is a breakthrough technology being developed recently in the field of electronics industry and has many excellent features, such as operation frequency of above 2 GHz, ultra-high Q factor and durable mechanical property, etc. The unique features of the SMR-FBAR make it not only be a hot spot in labs, but also attractive in particular applications. For instance, SMR-FBAR can be used to create the essential frequency shaping elements found in the third generation of wireless communication systems, including filters, duplexers, and oscillators. Materials are the key element in devices and their quality plays a critical role in determining the resonance characteristics of these acoustic resonators. In this paper, with the clue of the structure of device, the recent developments of materials used for solidly mounted film bulk acoustic resonators are reviewed, including piezoelectric films (AlN, ZnO, etc), high/low acoustic impedance materials and electrode films. The relationship between material properties and device performance is also discussed. Finally, the potential development direction on the investigation of materials used for solidly mounted film bulk acoustic resonators is prospected