Zirconium-Doped Hybrid Composite Systems for Ultrahigh-Temperature Oxidation Applications: A Review

Abstract

The re-entry phase of a space vehicle demands thermal shielding against the heat elicited by an aerodynamic heating process. The quantity of heat spawned in such process is close to 11.35 × 105 kJ m–2 and temperature reaching 8000 °C at the stagnation point on the surface of the re-entry vehicle. Ablative materials are effectual for heat shielding re-entry vehicles, and their performance is improved by various physicochemical techniques. Utilization of ultrahigh-temperature ceramics to enhance the performance of ablative materials has set a new milestone in heat shielding applications. The article briefly introduces the conditions that prevail during a re-entry phase, discusses thermophysical properties that are to be adorned by ablative materials other mere thermal insulation. This review article uniquely discusses the effect of the selection of ceramic filler system on the formation of an oxidation layer, the emissivity of the oxidation layer and thermophysical behavior of the oxidation layer.