Thermal protection material, adiabatic expansion section and preparation method of adiabatic expansion section

The invention provides a preparation method of a thermal protection material, which comprises the following steps: performing thin-passing on rubber, and mixing with cerium oxide to obtain a rubber compound green sheet; the rubber comprises ethylene propylene diene monomer, hydrogenated nitrile rubber, carboxy nitrile rubber, chloroprene rubber, silicone rubber or polyphosphazene rubber; pressing the rubber compound green sheet and carbon cloth to obtain a composite rubber green sheet; and vulcanizing the composite rubber green sheet to obtain the thermal protection material. The carbon cloth is used as a reinforcing material, the cerium oxide is used as a reinforcing filler and compounded with the ethylene propylene diene monomer, the hydrogenated butadiene-acrylonitrile rubber, the carboxyl butadiene-acrylonitrile rubber, the chloroprene rubber, the silicone rubber or the polyphosphazene rubber, the carbon cloth can keep the original structure in a high-temperature environment, and the effects of supporting