Integrated density gradient thermal protection material and preparation method thereof

Abstract

The invention provides an integrated density gradient thermal protection material and a preparation method thereof. The thermal protection material comprises a matrix and a reinforcement body, whereinthe matrix is of a network-shaped porous resin structure; the reinforcement body comprises a fiber reinforcement body inner layer with a second volume density and a fiber reinforcement body outer layer with a first volume density arranged on the inner layer; a network-shaped porous structure is further dispersed and cured in the fiber reinforcement body outer layer and the fiber reinforcement body inner layer, and the first volume density is 0.5-2.0 g / cm<3>; and the second volume density is 0.05-0.4 g / cm<3>. The method comprises the following steps: preparing the reinforcement body; preparinga solution of a matrix raw material; injecting the solution into the reinforcement body to enable the reinforcement body to fully infiltrate the solution; and curing at a resin curing temperature. The technical problems that an outer heat-proof layer of an existing heat-proof material is prone to oxidation and cannot be used for a long time, an inner heat-insulating layer is long in forming process period and high in cost, and the overall heat-proof effect is poor due to a preparation method can be solved.

Description

technical field [0001] The invention belongs to the technical field of composite materials, and in particular relates to an integrated density gradient thermal protection material and a preparation method thereof. Background technique [0002] The aircraft is facing the development trend of fast flight speed and long flight distance. At the same time, it needs to deal with the thermal environment characterized by high heat flow, high enthalpy, and high stagnation point pressure. Low coefficient, anti-ablation, anti-scouring and other characteristics. [0003] At present, the heat protection materials used in aircraft include two parts: outer heat protection materials and inner heat insulation materials. External heat protection materials include carbon-carbon composite materials, silicon carbide ceramic matrix and other reusable heat protection materials, as well as resin-based and rubber-based ablation heat protection materials. Carbon-carbon and ceramic matrix composite ...

AI Technical Summary

Problems solved by technology

Carbon-carbon and ceramic matrix composite materials have excellent temperature and erosion resistance, but carbon materials will undergo oxidation reaction in an oxygen-rich environment, and the material performance will decrease rapidly; Erosion resistance and other properties, the material density is relatively high, and the thermal conductivity is high. It is often used in a short-term thermal protection system (100s), and cannot be applied to the thermal protection of a long-term aircraft, which has certain limitations.

The inner heat insulation material is an airgel heat insulation material, which mainly plays the role of heat insulation, but it needs to be dried by supercritical drying method, the molding process cycle is too long, and the manufacturing cost is too high

[0004] In addition, the entire thermal protection system needs to be bonded and fixed with an adhesive after the outer heat-resistant material and the inner thermal insulation material are formed separately, and the temperature resistance and reliability of the adhesive will seriously affect the overall protective effect of the thermal protection

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