Method for preparing high alpha-phase silicon nitride by utilizing porous silicon

A technology of phase silicon nitride and porous silicon, which is applied in the field of preparing high-alpha phase silicon nitride by using porous silicon, can solve the problems that the degree of nitriding is difficult to control, it is not suitable for industrial production, and the operation process is complicated, so as to achieve short production cycle , Inhibit self-sintering, simple preparation process

Active Publication Date: 2015-04-08
ZHEJIANG UNIV
View PDF6 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although this scheme can also increase the content of α-phase to a certain extent, it requires high equipment, and the operation process is complicated. The degree of nitriding in the first step is difficult to control, the repeatability is poor, and it is not suitable for industrial production.

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
  • Method for preparing high alpha-phase silicon nitride by utilizing porous silicon
  • Method for preparing high alpha-phase silicon nitride by utilizing porous silicon
  • Method for preparing high alpha-phase silicon nitride by utilizing porous silicon

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] The preparation process of porous silicon raw material is as follows:

[0030] Place magnesium silicide in a high-temperature heat treatment furnace for heat treatment, the reaction temperature is 450°C, and the time is 35 hours. During the whole heat treatment process, a mixed gas of argon and oxygen is introduced, and the content of oxygen is 25%.

[0031] The product obtained above was washed three times with 1Mol / L hydrochloric acid and deionized water respectively, then centrifuged, and then dried under vacuum.

[0032] The above-mentioned self-prepared porous silicon raw material is used, the particle size is 1-5 μm, and the specific surface area is greater than 100m 2 / g, the pore size of porous silicon is 75-150nm. Under a nitrogen atmosphere, keep warm at 1300°C for 25 hours to obtain loose high-α-phase silicon nitride. The obtained silicon nitride is then ball-milled using a planetary ball mill. The grinding ball is hot-pressed and sintered silicon nitride ...

Embodiment 2

[0035] The preparation process of porous silicon raw material is as follows:

[0036] Place magnesium silicide in a high-temperature heat treatment furnace for heat treatment, the reaction temperature is 500°C, and the time is 30 hours. During the whole heat treatment process, a mixed gas of argon and oxygen is introduced, and the content of oxygen is 15%.

[0037] The product obtained above was washed three times with 1Mol / L hydrochloric acid and deionized water respectively, then centrifuged, and then dried under vacuum.

[0038] The above-mentioned self-prepared porous silicon raw material is used, the particle size is 7.5-10 μm, and the specific surface area is greater than 100m 2 / g, the porous silicon pore size is 100-200nm. Under a nitrogen atmosphere, keep warm at 1320°C for 20 hours to obtain loose high-α-phase silicon nitride. The obtained silicon nitride is then ball-milled using a planetary ball mill. The grinding ball is hot-pressed and sintered silicon nitride ...

Embodiment 3

[0041] The preparation process of porous silicon raw material is as follows:

[0042] The magnesium silicide is placed in a high-temperature heat treatment furnace for heat treatment, the reaction temperature is 600°C, and the time is 20 hours. During the whole heat treatment process, a mixed gas of argon and oxygen is introduced, and the content of oxygen is 10%.

[0043] The product obtained above was washed three times with 1Mol / L hydrochloric acid and deionized water respectively, then centrifuged, and then dried under vacuum.

[0044] The above-mentioned self-prepared porous silicon raw material is used, the particle size is 10-20 μm, and the specific surface area is greater than 100m 2 / g, the pore size of porous silicon is 150-500nm. Under a nitrogen atmosphere, keep warm at 1350°C for 15 hours to obtain loose high-α-phase silicon nitride. The obtained silicon nitride is then ball-milled using a planetary ball mill. The grinding ball is hot-pressed and sintered silic...

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 diameteraaaaaaaaaa
specific surface areaaaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing high alpha-phase silicon nitride by utilizing porous silicon. The method comprises the following steps: with the porous silicon as a raw material, in the nitrogen atmosphere, sequentially carrying out treatments including high-temperature calcination and grinding to obtain the high alpha-phase silicon nitride. With the adoption of the method of preparing the high alpha-phase silicon nitride by utilizing the porous silicon, the silicon nitride with high alpha phase content and uniform particle size distribution is efficiently prepared. The method is simple in process, controllable in performance, short in production period and low in cost, is capable of greatly lowering the production energy consumption and is suitable for large scale industrial production.

Description

technical field [0001] The invention relates to the field of silicon nitride preparation, in particular to a method for preparing high α-phase silicon nitride by using porous silicon. Background technique [0002] Silicon nitride is a widely used special ceramic material. The reason why it is widely used is because silicon nitride has many excellent properties. First of all, silicon nitride is a covalent bond compound with strong binding force, and it will not decompose until about 1800°C, so silicon nitride has good high temperature stability; secondly, silicon nitride is not compatible with most The molten metal reacts and does not react with all inorganic acids except hydrofluoric acid, so silicon nitride has very good resistance to chemical corrosion; in addition, silicon nitride has light specific gravity, high strength, high hardness, Wear resistance and other advantages. Therefore, silicon nitride can be found in a wide range of fields such as metallurgy, automobil...

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): C01B21/068
Inventor 张亚光杜宁张辉杨德仁
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