High-strength, high-toughness and high-thermal-conductivity silicon nitride ceramic material and preparation method thereof

A technology for silicon nitride ceramics and raw materials, which is applied in the fields of high thermal conductivity silicon nitride ceramic materials and their preparation, high strength and high toughness, and can solve the problems of limited large-scale application, low thermal conductivity of ceramics, poor mechanical properties, etc. , to achieve the effect of reducing the volume fraction of glass phase, high thermal conductivity, and reducing glass phase content

Active Publication Date: 2020-05-26
江西中科上宇科技有限公司
View PDF10 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

where Al 2 o 3 Ceramics have the lowest thermal conductivity and poor mechanical properties, which can only meet low-end applications; AlN has good thermal conductivity, but its poor mechanical properties and low reliability limit its large-scale application

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-strength, high-toughness and high-thermal-conductivity silicon nitride ceramic material and preparation method thereof
  • High-strength, high-toughness and high-thermal-conductivity silicon nitride ceramic material and preparation method thereof
  • High-strength, high-toughness and high-thermal-conductivity silicon nitride ceramic material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0034] As an example of the preparation of a mixed powder, including: α-Si 3 N 4 The powder is mixed with the sintering aid, and the uniformly mixed powder is obtained through the processes of ball milling, drying and sieving. The ball milling can adopt vacuum ball milling tank wet ball milling, and the atmosphere in the ball milling tank can be vacuum or filled with Ar and N 2 , wet ball milling uses alcohol as a solvent, the ratio of material: solvent can be (1:1) ~ (3:1), the ratio of material: ball can be (1:1) ~ (5:1), and the number of rotations of the ball mill is 200 ~500rpm, ball milling time is 4~20h. Drying can be carried out by rotary evaporation drying or vacuum drying, and the whole drying process can be carried out under vacuum, Ar, N 2 etc. in a protective atmosphere. Wherein, the drying temperature may be 50°C-100°C, and the drying time may be 8-24 hours. The mesh number of the sieve can be 60-300 mesh.

[0035] The mixed powder is pressed into shape to ...

Embodiment 1

[0046] With 0.5wt% Y and 1.5wt% MgO as sintering aids, and 98wt% α-Si 3 N 4 The powder is mixed by ball milling, dried and sieved to obtain a uniformly mixed powder; then it is dry-pressed under a pressure of 20MPa, and then subjected to cold isostatic pressing under a pressure of 250MPa; the green body obtained is put into a BN crucible , pre-sintered at 800°C for 4h in an Ar atmosphere; then the pre-sintered green body was sintered at 1900°C under pressure, with a heating rate of 10°C / min, N 2 The pressure is 1MPa, and the holding time is 4h; after sintering, cool to 1200°C at a cooling rate of 10°C / min, and then cool to room temperature with the furnace.

[0047] The thermal conductivity of the silicon nitride ceramic material prepared in Example 1 is 95.2W / (m·K), the three-point bending strength is 713±21MPa, and the fracture toughness is 9.91±0.19MPa·m 1 / 2 .

Embodiment 2

[0049] With 2.5wt% Y and 1.5wt% MgO as sintering aids, and 96wt% α-Si 3 N 4 The powder is mixed by ball milling, dried and sieved to obtain a uniformly mixed powder; then it is dry-pressed under a pressure of 30MPa, and then subjected to cold isostatic pressing under a pressure of 300MPa; the green body obtained is put into a BN crucible , pre-sintered at 1400°C for 6h in an Ar atmosphere; then the pre-sintered green body was sintered at 1850°C under pressure, with a heating rate of 5°C / min, N 2 The pressure is 1MPa, and the holding time is 4h; after sintering, cool to 1000°C at a cooling rate of 10°C / min, and then cool to room temperature with the furnace.

[0050] The thermal conductivity of the silicon nitride ceramic material prepared in Example 2 is 87.6W / (m K), the three-point bending strength is 1018±29MPa, and the fracture toughness is 8.51±0.21MPa·m 1 / 2 .

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
flexural strengthaaaaaaaaaa
strengthaaaaaaaaaa
toughnessaaaaaaaaaa
Login to view more

Abstract

The invention relates to a high-strength, high-toughness and high-thermal-conductivity silicon nitride ceramic material and a preparation method thereof. The silicon nitride ceramic material is prepared from the following raw materials: alpha-Si3N4 and a sintering aid, wherein the sintering aid is a rare earth metal simple substance and an alkaline earth metal oxide, and the total content of the sintering aid is 2-12wt%; the rare earth metal simple substance is Y; and the alkaline earth metal oxide is preferably at least one of MgO, CaO and BaO.

Description

technical field [0001] The invention relates to a high-strength, high-toughness, high-thermal-conductivity silicon nitride ceramic material and a preparation method thereof, in particular to a high-strength, high-toughness, high-thermal-conductivity ceramic material prepared by air pressure sintering using metal Y powder and MgO as sintering aids. Rate Si 3 N 4 The method for ceramic materials belongs to the field of inorganic non-metallic materials. Background technique [0002] In recent years, power semiconductor devices that can efficiently control and convert electric power have been widely used in fields such as industrial robots, hybrid vehicles, high-speed railways, and aerospace. In addition, researchers expect that wide-bandgap semiconductor materials such as silicon carbide and gallium nitride will gradually replace silicon chips, and power devices will develop in the direction of high voltage, high current, and high power density. Therefore, circuit substrates...

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): C04B35/584C04B35/64
CPCC04B35/584C04B35/64C04B2235/6562C04B2235/6567C04B2235/658C04B2235/9607C04B2235/96
Inventor 曾宇平王为得左开慧夏咏锋姚冬旭尹金伟梁汉琴
Owner 江西中科上宇科技有限公司
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