Thermal shock resistance and failure mechanisms of high temperature resistant radar and infrared compatible stealth coatings

Abstract

The compatibility stealth coatings for aircrafts application have attracted widely concerns recently in aerospace engineering. In this work, the high temperature resistant radar and infrared compatible stealth coating (HRISC) system was prepared first, which mainly consisted of seven layers, such as low-emissivity layer, thermal barrier ceramic layer 1/2 (TBC1, TBC2), lossy layer, matching layer, etc. And then, the microstructures and thermal shock behaviors of HRISC system was determined. Results showed that the microstructures obviously changed after cyclic thermal shock tests. The horizontal cracks extended at the interface, leading to the matching layer and above detaching from the HRISC system after 70 thermal shock cycles. The numerical simulations showed that the interface of matching layer and TBC1 was under the highest stress state and prone to failure. In addition, the residual interfacial adhesion strength of the HRISC system after thermal shock tests was tested. The results showed that the failure position was at the interface between the matching layer and TBC1, and the interfacial adhesion strength decreased obviously with the increase of thermal shock cycles. All these can provide reference for the design and failure analysis of HRISC system in engineering application.