Check patentability & draft patents in minutes with Patsnap Eureka AI!

High-porosity porous fused quartz with directional pore structure and preparation method thereof

A technology of fused silica and fused silica powder, which is applied in the field of preparation of porous fused silica, which can solve the problems of harsh freeze-drying conditions, poor strength of the dried body, and low saturated vapor pressure, and achieve shortened drying time, small drying shrinkage, and saturated The effect of high vapor pressure

Pending Publication Date: 2020-11-10
SHANGHAI INST OF CERAMIC CHEM & TECH CHINESE ACAD OF SCI
View PDF8 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the high surface tension of water, during the freezing process, the ice crystals tend to grow in dendrites, resulting in poor strength of the dried body. At the same time, the saturated vapor pressure of water is small, and it is not easy to volatilize. The freeze-drying conditions are harsh and the time is long.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • High-porosity porous fused quartz with directional pore structure and preparation method thereof
  • High-porosity porous fused quartz with directional pore structure and preparation method thereof
  • High-porosity porous fused quartz with directional pore structure and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0031] Preparation of slurry. The silicon nitride powder (as a sintering aid) and the fused silica powder are ball milled and mixed with the tert-butanol solution mixed with a dispersant according to a certain volume ratio to form a uniform and stable slurry. Wherein, the mass of the sintering aid can be 5-20% of the mass of the fused silica powder, and the adjustment of the diameter of the directional hole can be realized through the control of the added amount. The fused silica particles contained in the fused silica slurry have a median diameter of 1 to 5 μm. The median particle size of the silicon nitride powder can be 0.5-1.5 μm. Wherein, the mass ratio of the dispersant to the fused silica powder is 1: (18-22). The solid content of the finally obtained slurry can be controlled between 10-20 vol%, wherein the solid content is the ratio of silicon nitride powder and fused silica powder to the total volume of the slurry.

[0032] Freeze to form. The slurry is poured int...

Embodiment 1

[0039] Weigh 1g of dispersant (polyvinyl butyral) and 70g of tert-butanol and stir and mix to form an alcohol solution, weigh 20g of fused silica powder and 3g of sintering aid (silicon nitride) into the above alcohol solution, and ball mill for 2 hours Finally, the slurry is prepared; the prepared slurry is then poured into a mold, which consists of a cylindrical polytetrafluoroethylene plastic and a copper plate bottom. And during freeze molding, the outside of the mold is covered with multiple layers of asbestos felt insulation materials except the bottom, and the mold is placed in a refrigerator at -18°C for one-way freezing and molding for 12 hours to obtain a solidified body. After demoulding, transfer the frozen body In the freeze dryer, the drying is completed in a low-temperature vacuum environment to obtain a fused silica dry body; then sintered, in an air atmosphere, first heated to 1000 °C at a heating rate of 10 °C / min, and then heated at a heating rate of 5 °C / min...

Embodiment 2

[0041] Weigh 1.25g of dispersant (polyvinyl butyral) and 70g of tert-butanol and stir and mix to form an alcohol solution, weigh 23g of fused silica powder and 3.45g of sintering aid (silicon nitride) and add them to the above alcohol solution, The slurry was prepared after ball milling for 2 hours; then the prepared slurry was injected into the mold, and the mold was placed in a -18°C refrigerator for one-way freezing and molding for 12 hours to obtain a solidified green body. After demoulding, the frozen green body was transferred to a freezer In the dryer, drying is completed in a low-temperature vacuum environment to obtain a fused silica dry body; followed by sintering, first heating to 1000 °C at a heating rate of 10 °C / min, and then heating to 1250 °C at a heating rate of 5 °C / min. Keep warm for 2h. The prepared fused silica foam has a porosity of 81.66%, an average pore diameter of 68.3 μm, a compressive strength of 2.67 MPa, and an average sound absorption coefficient...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
pore sizeaaaaaaaaaa
diameteraaaaaaaaaa
compressive strengthaaaaaaaaaa
Login to View More

Abstract

The invention relates to high-porosity porous fused quartz with an oriented pore structure and a preparation method thereof. The preparation method comprises the following steps: (1) dispersing fusedquartz powder and a sintering aid into a tert-butyl alcohol solution containing a dispersing agent to obtain slurry, wherein the sintering aid is silicon nitride powder, and the addition amount of thesintering aid is 5-20wt%, preferably 5-15wt%, of the mass of the fused quartz powder; (2) pouring the obtained slurry into a mold, carrying out directional freezing molding under a one-way cold source, and carrying out demolding and freeze drying to obtain a green body; and (3) sintering the obtained green body at 1200-1300 DEG C for 2-10 hours to obtain the porous fused quartz with the orientedpore structure.

Description

technical field [0001] The invention relates to a preparation method of low-shrinkage porous fused silica with high porosity and directional pore structure, belonging to the technical field of inorganic materials. Background technique [0002] Porous ceramics are a class of ceramic materials with a large number of closed pores or interconnected open pores inside. Due to the large number of pores in porous ceramics, it has excellent characteristics such as low density, low thermal conductivity, low dielectric constant, high permeability, and high specific surface area, as well as excellent high temperature resistance, acid and alkali resistance of ceramic materials. Therefore, porous ceramics are widely used in metallurgical and chemical fields such as purification and separation, flue gas filtration, sound absorption and vibration reduction, thermal insulation, and catalytic carriers. [0003] Porous fused silica material combines the advantages of porous ceramics and oxide...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C04B35/14C04B35/64C04B38/00
CPCC04B35/14C04B35/64C04B38/0054C04B2235/3873C04B2235/606C04B2235/6562C04B2235/6567C04B2235/94C04B2235/96C04B38/0074
Inventor 曾宇平杜中培左开慧夏咏锋姚冬旭尹金伟梁汉琴
Owner SHANGHAI INST OF CERAMIC CHEM & TECH CHINESE ACAD OF SCI
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com