Nanometer composite powder of silicon carbide/aluminum oxide-calcium oxide core-shell structure and preparation method

A nanocomposite powder and core-shell structure technology, applied in the field of material science, can solve the problems of low thermal conductivity of cordierite eutectic point and limit the high-temperature performance of honeycomb materials, so as to maintain high-temperature performance without deterioration and solve the problem of sintering temperature , the effect of excellent high temperature resistance

Inactive Publication Date: 2009-01-07
ZHEJIANG UNIV
View PDF1 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, there is research and development work on other materials as the second phase combined with silicon carbide. For example, Chinese patent application CN1800097 discloses a silicon carbide-cordierite composite porous ceramic and its preparation method, but the eutectic point of cordierite (1350°C) The problem of low thermal conductivity and low thermal conductivity will still be the technical bottleneck that limits the high-temperature performance of this type of composite ceramic honeycomb material.

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
  • Nanometer composite powder of silicon carbide/aluminum oxide-calcium oxide core-shell structure and preparation method
  • Nanometer composite powder of silicon carbide/aluminum oxide-calcium oxide core-shell structure and preparation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Take 10 kg each of large silicon carbide aggregates with an average particle size of 25 microns and small silicon carbide aggregates with an average particle size of 2 microns, and use the following same process conditions to coat alumina and calcium oxide shells.

[0028] Take by weighing 10 kilograms of SiC raw materials, 1.5 kilograms of alumina source raw materials Al(NO 3 ) 3 9H 2 O, 40 kg of water, prepared into a uniform suspension under stirring conditions. Then, slowly add ammonia water as a pH adjuster to the suspension to control the pH of the solution at 5.5, and the precipitation reaction takes about 20 minutes. After that, the reaction is hydraulically filtered and the precipitate is washed with water once. dried, then placed in an alumina crucible, placed in a muffle furnace for heat treatment at 280°C for 1 hour, and a product coated with an aluminum shell was obtained once; The intermediate product of the aluminum oxide layer.

[0029] Then the abov...

Embodiment 2

[0032] Take respectively 10 kilograms of large particle silicon carbide aggregates with an average particle diameter of 35 microns and small particle silicon carbide aggregates with an average particle diameter of 3 microns, adopt the same alumina and calcium oxide coating process conditions as in Example 1, A silicon carbide / alumina-calcium oxide core-shell nanocomposite powder coated with two layers of alumina and two layers of calcium oxide is obtained. Adopt the same extrusion molding formula as in Example 1 to obtain a dry biscuit, put the above-mentioned extruded biscuit into an atmosphere sintering furnace, vacuumize and fill with nitrogen protection, heat up to 800 °C at 10 °C / min, and keep it warm 1 hour; continue to fill with nitrogen protection, heat up to 1525°C at 10°C / min, and keep warm for 3 hours; after that, cool down to 800°C at 20°C / min; then turn off the heating power and gas valve, and cool down to room temperature with the furnace. A Ca-α-sialon-combined ...

Embodiment 3

[0034] Take respectively 10 kilograms of large particle silicon carbide aggregates with an average particle diameter of 25 microns and small particle silicon carbide aggregates with an average particle diameter of 2 microns, adopt the same aluminum oxide and calcium oxide coating process conditions as in Example 1, The number of coating layers of alumina is 1, and the number of coating layers of calcium oxide is 3 layers. A silicon carbide / alumina-calcium oxide core-shell nanocomposite powder coated with 1 layer of alumina and 2 layers of calcium oxide is obtained. Adopt the same extrusion molding formula as in Example 1 to obtain a dry biscuit, put the above-mentioned extruded biscuit into an atmosphere sintering furnace, vacuumize and fill with nitrogen protection, heat up to 850 °C at 10 °C / min, and keep it warm 1.5 hours; continue to fill with nitrogen protection, heat up to 1500°C at 10°C / min, and keep warm for 5 hours; after that, cool down to 800°C at 20°C / min; then turn...

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
particle sizeaaaaaaaaaa
thicknessaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses carborundum/alumina-calcium oxide nano-compound powder in core-shell structure, which is nano-compound powder with engineering ceramics-used carborundum granules as the core and nano-thickness alumina-calcium oxide covered on the surface as the shell. The invention further discloses the application of the nano-compound powder in the preparation of honeycomb ceramics. Carborundum honeycomb ceramics can be gotten with Ca-Alpha theron ceramic phase as carborundum granule aggregate coupling phase by using the nano-compound powder as aggregate at the temperature far below the carborundum recrystallization temperature and under specific nitrogen atmosphere processing conditions. The carborundum honeycomb ceramics prepared which takes Ca-Alpha theron ceramic phase as carborundum granule aggregate coupling phase has the advantages of low sintering temperature, high strength and high resistance to high temperature and so on.

Description

technical field [0001] The invention belongs to the technical field of material science, and in particular relates to a nanocomposite powder with a silicon carbide / alumina-calcium oxide core-shell structure, a preparation method thereof, and an application in honeycomb ceramic materials. Background technique [0002] Diesel vehicles have the advantages of high power and high combustion efficiency, but their exhaust exhaust contains a large number of carbon-containing particles that are likely to cause environmental pollution and pose a serious threat to human health. Therefore, it is necessary to develop a method that can efficiently remove carbon-containing particles in the exhaust Porous honeycomb ceramic material for diesel vehicle exhaust particulate filter (Diesel Particulate Filter, DPF for short). [0003] DPF generally adopts a wall-flow honeycomb ceramic filter structure; in terms of materials, although a lot of material varieties have been researched and reported, ...

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): C04B35/628
Inventor 洪樟连张悦伟黄侃朱奇妙王民权
Owner ZHEJIANG 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