Thermostructural Response of a Spatially Graded Metal-Ceramic Composite Panel Subjected to High-Speed Flight Loads

Abstract

The response of a thermally and mechanically loaded metal-ceramic spatially graded composite structural panel is considered. The load profiles that are representative of in-flight high-speed loading conditions have been evaluated. Thermal loads due to aerodynamic heating include laminar, turbulent, and transitional (laminar to turbulent) heat fluxes applied on the outer surface of the panel. One- and two-directional graded panels are studied using finite element analysis. The effect of grading on temperature gradients and stress concentrations are investigated. The benefits of the spatial grading for the panels subjected to uniform and nonuniform surface heat fluxes are examined, and the results are compared with those of a Ti-6Al-4V panel with an Exelis Acusil II syntactic foam thermal protection system (TPS). The results show that through-thickness temperature gradients are effectively eliminated in the panel graded in the through-thickness direction as compared with the traditional panel with the attached TPS. Additional grading in the direction parallel to the flow significantly reduces in-plane surface temperature gradients when the panel is subjected to nonuniform transitional heat flux.