A kind of graphite/silicon carbide thermal insulation backing and preparation method thereof

Abstract

The invention provides a graphite / silicon carbide thermal insulation backing and a preparation method thereof. The graphite / silicon carbide thermal insulation backing is composed of solid and relatively loose pore parts, and the size of all pores is controlled below φ1mm, and exists in isolation and dispersion, and its volume ratio does not exceed 20% (as shown in Figure 1). The preparation method is as follows: first prepare graphite / phenolic resin mixed powder, then use selective laser sintering molding technology to prepare graphite / silicon carbide heat insulation backing green body, and finally undergo secondary curing, vacuum pressure impregnation with phenolic resin solution, carbonization, vacuum Pressure impregnation of silica sol and high temperature hot pressing sintering to obtain graphite / silicon carbide thermal insulation backing. The method has the characteristics of high material utilization rate, no dust pollution, low production cost, controllable comprehensive performance and the like. The prepared graphite / silicon carbide thermal insulation backing has low density, high compressive strength, high temperature resistance, low thermal conductivity and good thermal insulation effect.

Description

technical field [0001] The invention belongs to the technical field of inorganic non-material forming and manufacturing, and specifically relates to a graphite / silicon carbide thermal insulation backing and a preparation method thereof. Background technique [0002] In order to prevent the metal casing of the small solid rocket motor from being burned by gas or reduce its strength due to overheating and endanger the integrity of its structure, and at the same time reduce the obvious infrared signal characteristics caused by heat dissipation, the metal casing of the engine must be inspected. Reliable protection. At present, the combined passive thermal protection structure of nozzle 1 (inner layer), heat insulation backing 2 (middle layer) and metal shell 3 (outer layer) is generally used (such as figure 2 As shown), the thermal insulation backing 2 is assembled between the nozzle 1 and the metal shell 3, and plays dual roles of bearing and heat insulation. Therefore, the t...

AI Technical Summary

Problems solved by technology

Compared with ablative materials such as glass / phenolic resin or carbon / phenolic resin or glass / silicone resin, rigid insulation tiles have the advantages of high temperature resistance, high dimensionality, and reusability, but their compression resistance is insufficient, making it difficult to made into complex hollow structures

Images