Method for preparing porous silicon carbide ceramic with high porosity

A technology of porous silicon carbide and high porosity, applied in ceramic products, applications, household appliances, etc., can solve the problems of large pore size and high reaction temperature of porous silicon carbide materials, and achieve uniform pore size distribution, high porosity, and simple process implementation Effect

Active Publication Date: 2005-11-23
TSINGHUA UNIV
View PDF4 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

After these raw materials are made into mud, porous silicon carbide ceramics are made through processes such as molding, drying, cracking and high-temperature sintering. The pore size, porosity and other properties can be controlled by changing the ratio of raw materials and process conditions. The reaction temperature is very high (2200~2600℃)
U.S. Patent US005248462A has also introduced a kind of silicon source and carbon source with silicon powder and carbon powder respectively, and lead ball or other spherical materials are the conti

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

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0012] The invention provides a method for preparing porous silicon carbide ceramics with high porosity. The method uses silicon powder (silicon source), phenolic resin (binder) and alcohol as raw materials, and undergoes inclusion mixing process, low-temperature and low-pressure molding, and high-temperature carbonization. After the four steps of treatment and high-temperature sintering, a high-porosity porous silicon carbide ceramic material is obtained, which is characterized in that: the specific process steps are:

[0013] 1) According to the mass ratio of silicon powder, phenolic resin and alcohol 1: (0.25 ~ 1.1): 2 mixed into a slurry;

[0014] 2) Preparation of entrapped powder: heat-treat the mixed slurry at 30-80°C, and stir for 30-120 minutes; then cool down to below 10°C, then cold-treat in the range of 0-10°C, and stir for 10-60 minutes at the same time; The mixed slurry is injected into water with an injection pressure of 0.2-1.2MPa; aging treatment is carried ou...

Embodiment 1

[0021] First, mix silicon powder, barium phenolic resin and alcohol (mass ratio 1:0.25:2) by inclusion mixing process, heat treatment at 30°C for 120 minutes, cold treatment at 0°C for 10 minutes, injection pressure 0.2MPa, aging treatment at 30°C for 120 minutes, Vacuum dry at 40°C for 120min to obtain inclusion-blending powder; then heat-preserve the inclusion-blending powder at 60°C and 0.05MPa pressure for 120min to obtain a ceramic green body; High-temperature carbonization treatment, the temperature is 600°C, the heating rate is 0.3°C / min, and the heat preservation is 240min; finally, the powder obtained by the carbonization treatment is subjected to high-temperature sintering under the protection of argon (50ml / min), the temperature is 1300°C, and the heating rate is 1°C / min, heat preservation for 8 hours to form a high-porosity porous silicon carbide ceramic material.

Embodiment 2

[0023] First, mix silicon powder, barium phenolic resin and alcohol (mass ratio 1:0.25:2) by inclusion mixing process, heat treatment at 30°C for 120 minutes, cold treatment at 0°C for 10 minutes, injection pressure 0.2MPa, aging treatment at 30°C for 120 minutes, Vacuum dry at 40°C for 120min to obtain inclusion-blending powder; then heat-preserve the inclusion-blending powder at 80°C and 0.1MPa pressure for 60min to obtain a ceramic green body; High-temperature carbonization treatment, the temperature is 800°C, the heating rate is 0.5°C / min, and the heat preservation is 120min; finally, the powder obtained by the carbonization treatment is subjected to high-temperature sintering under the protection of argon (100ml / min), the temperature is 1500°C, and the heating rate is 2.5°C / min, heat preservation for 4 hours to form a high-porosity porous silicon carbide ceramic material.

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

No PUM Login to view more

Abstract

The invention discloses a method for preparing porous silicon carbide ceramic with high porosity which comprises preparing mix-coated powder from silicon powder, phenol resin and ethanol by a predetermined proportion, then carrying out low-temperature low-pressure modeling to produce ceramic blanks, high temperature carbonizing the ceramic blanks, finally sintering at high temperature to obtain the end product whose factor of porosity is greater than 80%.

Description

technical field [0001] The invention belongs to the technical field of ceramic material preparation, in particular to a method for preparing silicon carbide ceramics with high porosity. technical background [0002] Porous silicon carbide materials have been Widely used in aerospace, energy, machinery, metallurgy, chemical industry, environmental protection, military industry, electronics and biology and other disciplines, involving fluid separation and filtration, diffusion, heat insulation, sound absorption, sensing, electrochemical process and catalytic reaction engineering It can be used to make filters, separation and catalyst supports, etc. Therefore, the research on porous silicon carbide materials has attracted great attention from the global material science community, new preparation methods have emerged, and the preparation system has been continuously improved. [0003] The preparation of porous silicon carbide also has bibliographical reports, and Chinese paten...

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
IPC IPC(8): C04B35/584
Inventor 时利民赵宏生唐春和闫迎辉梁彤祥
Owner TSINGHUA UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap