Search

To address the urgent demand to test mechanical/thermal/oxidation key performance parameters for new ultra-high-temperature structures, a radiation thermo-mechanical joint test system that can perform fracture performance tests under an extremely high temperature oxidation environment (1500 °C) was designed and implemented. Key performance parameters, such as the fracture strength and time to failure of high-temperature-resistant C/SiC composite structure, were tested and measured in oxidation environments up to 1500 °C. In present test, when the temperature rises from 1000 °C to 1500 °C, the fracture load of C/SiC structure decreased by 47.5%, and the time to failure reduced to 50.1% of that at 1000 °C. This extremely high temperature load test system provides an important thermo-mechanical joint test technique to study the mechanical properties of structure and material for hypersonic aircraft under an oxidation environment. The test shows that a high-temperature preload significantly enhances the fracture strength of C/SiC composite structure. In present work, the fracture strength increases by 38% and the time to failure increases by 61.1% for C/SiC. The test results can be used to improve the safety, reliability, and strength of composite components of hypersonic aircraft under extreme thermal environments.

Because hypersonic vehicles face environments with extremely high temperatures in which the vehicles׳ outer shells experience single-sided heating and the temperature varies nonlinearly over time, a self-designed radiation and one-sided heating test apparatus is established in this paper, which can perform the thermal insulation performance test for lightweight ceramic thermal protection materials of hypersonic aircraft in extremely high-temperature/oxidation environments up to 1700 °C. Meanwhile, experimental research on thermal insulation performance of a lightweight ceramic material specimen and a novel ceramic-nanomaterial hybrid structure in high-temperature/oxidation environments up to 1700 °C was carried out. Different materials alone and in combination were analyzed and compared to select the most effective insulation scheme. It is found that the thermal insulation performance of the ceramic-nanomaterial hybrid thermal protection structure can be increased approximately 50% compared with that of the lightweight ceramic material specimen. Additionally, non-linear time-varying thermal environments with extremely high temperatures were generated and the thermal insulation performance tests were performed in this paper. The present work provides an important test method for the thermal protection design of hypersonic aircraft through the establishment and application of an extreme high-temperature/oxidation test system which can create one-sided heating, time-varying thermal environments.