Investigation on the Reliability of an Ablation Thermal Protection Coating with Adjustable Thickness under Aerothermal–Vibration Coupling Environment

Abstract

Advanced thermal protection system is the core component of supersonic vehicles. A novel hydroxyl‐terminated silicone oligomer‐bridged epoxy resins (PSG)‐based ablation thermal protection coatings (ATPCs) with different thickness are fabricated. The thermal insulation and structural reliability of the coatings are investigated by an aerothermal–vibration coupling test system. During the test, the heat flux of the surface of ATPCs ranges from 400 to 700 kW m−2. Meanwhile, the vibration load is a random vibration with frequency range of 20–2000 Hz and root mean square of total acceleration (Grms) of 15 g. The maximum surface and back‐face temperatures of the coating with the thickness of 2 mm reach 771.8 and 113.6 °C, respectively. Compared with epoxy resin‐based ATPCs, the PSG‐based ATPCs show excellent structural reliability during the test. Finally, the comprehensive properties of ATPCs with different thickness are also carefully studied. Results show that the reduction of thickness obviously suppresses the surface temperature (≈743.4 °C) and increase in back‐face temperature (≈241.5 °C) yet maintaining much higher structural reliability. This study provides a solution for obtaining excellent thermal insulation performance ATPCs with high structural reliability, which is highly desired in supersonic vehicles.

Effect of High-Temperature Thermal Shock on Solar Absorption Rate of Alumina Coating

“…In the aerospace industry, the use of thermal protective coatings is very common. The spraying of ablative thermal protective coatings (ATPCs) on aircraft, the high-entropy rareearth aluminate coatings prepared on the surface of nickel-based alloys, and the inorganic zirconium sol coatings prepared on the surface of aluminum alloys can play a good thermal protection role on the substrate [9][10][11][12]. However, the surface of a solar probe needs to withstand a high temperature of more than 1400 • C for a long time, and the stability of ordinary coating performance is difficult to ensure under the environment of a long time at 1400 • C. Research shows that alumina coatings can withstand the high temperature of 1400 • C and are one of the most suitable thermal protection coatings [13,14].…”