Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Graphite material with SiC doped layer and preparation method of graphite material

A technology of graphite material and doped layer, which is applied in the field of graphite material with SiC doped layer and its preparation, which can solve the problems of low density, high opening porosity of silicon carbide layer, poor corrosion resistance, etc., and improve the bonding strength Effect

Active Publication Date: 2017-12-29
NAT UNIV OF DEFENSE TECH
View PDF19 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But at the same time, the silicon carbide layer coated on the surface of the graphite substrate hinders the reaction between the molten silicon and the graphite substrate, and the unreacted molten silicon tends to nucleate and grow silicon grains on the surface of the silicon carbide coating when the temperature drops below the melting point. A large amount of unreacted solid silicon remains on the surface of SiC. These residual silicon are closely combined with the SiC layer, which increases the processing difficulty after siliconizing, and the corrosion resistance of silicon is worse than that of silicon carbide. The presence of residual silicon will weaken siliconizing. Corrosion resistance of post graphite materials
In vapor phase siliconizing technology, gas phase silicon enters the interior of the graphite matrix and reacts with carbon in situ to form silicon carbide, but the resulting silicon carbide layer has a higher opening porosity, lower density, and there is also the problem of more residual silicon on the surface

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
  • Graphite material with SiC doped layer and preparation method of graphite material
  • Graphite material with SiC doped layer and preparation method of graphite material
  • Graphite material with SiC doped layer and preparation method of graphite material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] A kind of preparation method of the graphite material with SiC doping layer of the present invention, comprises the following steps:

[0029] 1) Put the mixed powder consisting of silicon powder, flake graphite powder, boron nitride powder, aluminum oxide powder and yttrium oxide powder in a polyurethane ball milling tank, place the ball milling tank in a planetary ball mill, and turn it at 276 rpm Speed ​​ball milling for 0.5h to obtain the silicon source of the liquid phase siliconizing process; wherein, the mass fraction of silicon powder in the mixed powder is 88%, flake graphite powder, boron nitride powder, aluminum oxide powder and yttrium oxide powder in the mixed powder The mass fractions are 2.4%, 8.4%, 0.6%, 0.6%, respectively.

[0030] 2) Under the conditions of 1600°C and 22Pa high-temperature vacuum, use the silicon source obtained in step 1) to sinter the graphite substrate for liquid-phase siliconization (LSI) for 2 hours, so that the liquid-phase silico...

Embodiment 2

[0037] A kind of preparation method of the graphite material with SiC doping layer of the present invention, comprises the following steps:

[0038] 1) Put the mixed powder consisting of silicon powder, carbon powder, boron nitride powder, aluminum oxide powder and yttrium oxide powder in a polyurethane ball milling tank, and place the ball milling tank in a planetary ball mill at a speed of 276 rpm Ball milled for 0.5h to obtain the silicon source of the liquid phase siliconizing process; wherein, the mass fraction of silicon powder in the mixed powder is 84%, and the amount of flake graphite powder, boron nitride powder, aluminum oxide powder and yttrium oxide powder in the mixed powder The mass fractions are 3.2%, 11.2%, 0.8%, and 0.8%, respectively.

[0039] 2) Under the condition of 1600°C and 30Pa high-temperature vacuum, use the silicon source obtained in step 1) to sinter the graphite substrate for liquid-phase silicon infiltration (LSI) for 2 hours, so that the liquid...

Embodiment 3

[0042] A kind of preparation method of the graphite material with SiC doping layer of the present invention, comprises the following steps:

[0043] 1) Put the mixed powder consisting of silicon powder, carbon powder, boron nitride powder, aluminum oxide powder and yttrium oxide powder in a polyurethane ball milling tank, and place the ball milling tank in a planetary ball mill at a speed of 276 rpm Ball milled for 0.5h to obtain the silicon source of the liquid phase siliconizing process; wherein, the mass fraction of silicon powder in the mixed powder is 80%, and the amount of flake graphite powder, boron nitride powder, aluminum oxide powder and yttrium oxide powder in the mixed powder The mass fractions are 4%, 14%, 1%, 1%, respectively.

[0044] 2) Under the condition of 1600°C and 15Pa high-temperature vacuum, use the silicon source obtained in step 1) to sinter the graphite substrate for liquid-phase siliconization (LSI) for 2 hours, so that the liquid-phase silicon can...

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
Depthaaaaaaaaaa
Depthaaaaaaaaaa
Depthaaaaaaaaaa
Login to View More

Abstract

The invention discloses a graphite material with a SiC doped layer and a preparation method of the graphite material. The preparation method of the graphite material with the SiC doped layer comprises the following step: by taking mixed powder of silicon-containing powder and boron nitride as a silicon source, performing liquid-phase siliconing sintering on a graphite material, thereby obtaining the graphite material with the SiC doped layer. The graphite material with the SiC doped layer prepared by using the method comprises a graphite substrate and the SiC doped layer on the surface of the graphite substrate, the SiC doped layer is well combined with the graphite substrate without thermal mismatch, the graphite material is good in oxidation and corrosion resistance and relatively low in cost, and a small amount of silicon is adhered to the surface of the graphite material.

Description

technical field [0001] The invention belongs to the field of graphite materials, in particular to a graphite material with a SiC doped layer and a preparation method thereof. Background technique [0002] Graphite materials have the advantage of high temperature resistance, and are widely used in many high temperature structural fields. However, due to the oxidation and corrosion of graphite materials in high temperature and oxidizing environments, the components are gradually damaged. Therefore, improving the high-temperature oxidation resistance of graphite materials is of great significance for expanding the scope of use of graphite products and giving full play to the potential of graphite materials. [0003] High-purity silicon carbide (SiC) material has a series of excellent properties such as low density, high temperature resistance, oxidation resistance, erosion resistance, and corrosion resistance. It is an ideal material for improving the oxidation resistance of g...

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): C04B35/52C04B41/87
CPCC04B35/522C04B41/009C04B41/5059C04B41/87C04B41/4556
Inventor 刘荣军何嘉豪王衍飞贺鹏博曹英斌
Owner NAT UNIV OF DEFENSE TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products