Lightweight bearing nano ceramic aerogel based on electrospinning method and preparation method thereof

Abstract

The invention belongs to the technical field of ceramic materials, and discloses a light load-bearing nano ceramic aerogel based on an electrospinning method and a preparation method thereof.Polycarbosilane or polysilazane ceramic precursors are used as raw materials, tetrabutyl titanate or hafnium acetylacetonate or yttrium acetylacetonate is used as an additive, and the light load-bearing nano ceramic aerogel based on the electrospinning method is prepared. Nano Si-M-C ceramic fibers with a gradient structure are obtained through an electrostatic spinning process to serve as a first network, wherein M is Zr, Hf or Y; then, a ceramic precursor polyborosilazane or polysilazane is introduced into the first network through an infiltration process, a second network is obtained through supercritical drying, and the first network and the second network form a nano interpenetrating double-network structure; the obtained dual-network ceramic aerogel has excellent high-temperature heat insulation performance, oxidation resistance and good mechanical properties, can meet the thermal protection requirements of novel aircrafts in a 1700 DEG C high-temperature environment, and has important application prospects in the fields of military affairs, aerospace and the like as a novel strategic material.

Description

technical field [0001] The invention belongs to the technical field of ceramic materials, and in particular relates to a light-weight bearing nano-ceramic aerogel based on an electrospinning method and a preparation method thereof. [0002] technical background [0003] With the continuous development of aerospace technology, hypersonic vehicles have higher flight speeds and longer flight times in the atmosphere. The aerodynamic heating of the windward side and the leading edge of the wings of the aircraft is severe, and the thermal environment is extremely harsh. When the aircraft is flying in the atmosphere at a speed of Mach 8, the temperature at the nose cone is as high as 1793°C, and the temperature at the leading edge of the wing reaches 1455°C. In order to make its internal instruments and equipment work within the appropriate temperature range, an efficient thermal protection system must be used. Aerogel materials have low density and thermal conductivity, and are on...

AI Technical Summary

Problems solved by technology

However, both carbon fiber braids and carbon felts are micron-scale reinforcement phases with high density, and it is difficult to prepare lightweight ceramic matrix composites. In addition, the oxidation resistance of carbon reinforcements is also poor, which cannot meet the use requirements.

Although the domestically developed quartz fiber high-temperature insulation materials have a relatively mature preparation process and a large amount of effective experimental data have been obtained, the insulation materials still have problems such as low temperature resistance, uneven density, and unstable mechanical properties. On the one hand, fiber pretreatment, effective fiber dispersion, sintering process and other aspects still need to be further adjusted and optimized

Due to the special structure of traditional airgel, it can produce zero convection effect and long-distance effect, thereby greatly reducing heat convection and heat radiation. However, in the ultra-high temperature service environment, radiation heat transfer accounts for a large proportion, and the ultra-high temperature stability of traditional airgel and low thermal radiation resistance

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