High-density LAS microcrystalline glass fiber and preparation method thereof

Abstract

The invention provides a high-density LAS microcrystalline glass fiber and a preparation method thereof. The preparation method comprises the steps that lithium nitrate serves as a lithium source, aluminum nitrate serves as an aluminum source, tetraethyl orthosilicate and nano SiO2 particles serve as silicon sources, hydrochloric acid serves as a catalyst, a cosolvent absolute ethyl alcohol is added, an LAS precursor solution is prepared according to a certain proportion, then polymers such as PVP are added, a precursor solution with spinnability is obtained, electrostatic spinning parameters are set, and spinning is conducted; and then crystallization heat treatment is carried out on the collected fibers, grinding is carried out, and steps of ultrasonic crushing, volatilizing and drying are carried out to obtain nano LAS short fiber white powder. The material can be used as a reinforcing body to be added into LAS microcrystalline glass, crystals are induced to be separated out, and the mechanical property and the light transmittance performance of the microcrystalline glass are cooperatively improved.

Description

technical field [0001] The invention belongs to the field of preparation of engineering ceramics, and relates to a high-density LAS microcrystalline glass fiber and a preparation method thereof. Background technique [0002] Lithium aluminum silicon (Li 2 O-Al 2 o 3 -SiO 2 , LAS) glass ceramics are widely used in the manufacture of astronomical telescopes, cooking utensils, high-temperature electric light source glass, high-temperature Products such as heat exchangers, generation quartz glass, high temperature windows, and radar antenna shields have become one of the systems with the most research value. However, the crystal phases in LAS glass-ceramics are mainly β-spodumene and β-quartz solid solution from the residual glass matrix, due to the influence of crystal phase type, grain size, volume fraction (crystallinity), crystal phase and glass phase interface Due to the influence of residual stress caused by differences in bonding strength and thermal expansion coeffi...

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Problems solved by technology

However, this kind of carbide fiber-reinforced LAS glass-ceramic composites, on the one hand, is prone to oxidative failure and even catastrophic damage in the face of extreme high-temperature environments containing water vapor and oxygen.

On the other hand, the added fibers did not consider light transmission. These studies focused on the strengthening and toughening of LAS glass ceramics, and systematically analyzed the toughening mechanism of fibers and interfaces on crack deflection / bifurcation, bridging, and pull-out effects. , but did not explicitly mention the impact of these toughening measures on its semipermeability

Since the introduction of the heterogeneous fiber toughening phase will inevitably lead to unfavorable factors such as non-uniformly dispersed second phases, heterogeneous interfaces, and refractive index mismatches that strongly scatter and refract photons, it is difficult to ensure the excellent transparency of LAS glass ceramics. light performance

At present, glass fibers are mostly prepared by high-temperature melting-drawing method, which has problems such as high energy consumption and poor diameter controllability.

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