Ultra-High Temperature ZrB2–SiC–C Ceramics under High-Enthalpy CO2-Plasma Flow during Martian Atmospheric Entry Simulation

An ultra-high temperature ceramic material based on ZrB2-30 vol % SiC, modified with 10 vol % graphite, was fabricated by hot pressing at 1800°C under a pressure of 30 MPa. Its density, phase composition, and distribution of the constituents were characterized. The behavior of the material in a high-enthalpy CO2-plasma flow under conditions simulating the atmospheric entry of a Mars lander was investigated using the VGU‑4 radio-frequency induction plasma torch. Even at the maximum anode power of 72 kW, the surface temperature did not exceed 1450°C, resulting in a relatively low specific mass-loss rate of 3.1 × 10–4 g cm–2 min–1. The phase composition and microstructure of the oxidized surface were determined. The results demonstrate the need for systematic studies of ultra-high temperature ceramics exposed to high-velocity flows of dissociated CO2.