The Eagle's Ascent Vehicle was covered in a layer of heat-resistant material which was a part of the lander's heat-resistant tiles.
The Eagle lander, in its complete form, was a rounded lifting-body construction that had upper and lower components, a wing-fuselage fusion design. Its atmospheric entry was made with its belly facing down, and at its highest temperature, it could rise to at least 2000°C. Normal materials were undoubtedly unable to withstand such temperatures.
The heat-resistant tiles that lined the lander's belly weren't uniformly the same material. In the spots with the highest temperatures from adiabatic compression, such as the nose cone and flange, the engineers used carbon fiber to enhance the silicon-carbide materials. And this material was covered in phenolic impregnated carbon ablator. During the atmospheric entry, the heat-resistant tiles would rapidly rise in temperature to wick away the heat.
"It failed.
"It failed again.
