Interface modification method of SiCf/SiC composite material

A composite material and modification technology, which is applied in the field of interface modification of SiCf/SiC composite materials, can solve problems such as strong interface bonding and adverse effects on material properties, and achieve improved interface bonding, shortening the preparation cycle, and improving bending strength and fracture The effect of toughness

Active Publication Date: 2015-12-16
NAT UNIV OF DEFENSE TECH
View PDF2 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The commonly used fiber-matrix interface has a SiC interface, but the SiC coating acts as a SiC f The fiber-matrix interface of SiC / SiC composites can also lead to strong interfacial bonding and adversely affect the material properties.

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
  • Interface modification method of SiCf/SiC composite material
  • Interface modification method of SiCf/SiC composite material
  • Interface modification method of SiCf/SiC composite material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] (2) SiC obtained in step (1) f / PyC intermediate placed in LPVCS (liquid polycarbosilane containing vinyl) impregnation solution, vacuum impregnated for 24h. Take out the vacuum-impregnated intermediate and put it into a graphite mold, and carry out cross-linking molding under a flowing nitrogen atmosphere: at a heating rate of 2°C·min -1 , first raise the temperature to 180°C, keep it warm for 1h, then continue to raise the temperature to the crosslinking temperature of 250°C at the same heating rate, keep it warm for 1h, and the nitrogen flow rate is 100L h -1 . Take out the cross-linked intermediate and put it into a cracking furnace, and crack it in a flowing nitrogen atmosphere at a high temperature. The cracking temperature is 1100°C, and the heating rate is 8°C·min. -1 , the flow rate of nitrogen gas is 3L·h -1 . A total of 9 processes of vacuum impregnation-cross-linking molding-pyrolysis were carried out. Among them, the cross-linking molding process of the...

Embodiment 2

[0044] (2) SiC in step (1) f / h-BN intermediate placed in LPVCS impregnation solution, vacuum impregnation for 6h. Take out the vacuum-impregnated intermediate and put it into a graphite mold, and carry out cross-linking molding under a flowing nitrogen atmosphere: at a heating rate of 3°C·min -1 , first raise the temperature to 200°C, keep it warm for 0.5h, then continue to raise the temperature to the crosslinking temperature of 350°C at the same heating rate, keep it warm for 1.5h, and the nitrogen flow rate is 150L h -1 . Take out the cross-linked intermediate and put it into a cracking furnace, and crack it in a flowing nitrogen atmosphere at a high temperature. The cracking temperature is 1100°C, and the heating rate is 8°C·min. -1 , the nitrogen flow rate is 1L·h -1 . A total of 10 vacuum impregnation-cross-linking molding-pyrolysis processes were carried out. Among them, the cross-linking molding process of the first process cycle was assisted by hot molding, and t...

Embodiment 3

[0051] (2) SiC obtained in step (1) by LPCVD process f / PyC intermediate surface to prepare h-BN coating, the specific steps are: using boron trichloride and ammonia as source gas, nitrogen and hydrogen as dilution gas, SiC f The / PyC intermediate is placed in a CVD deposition furnace, and the chemical vapor deposition is carried out by the differential pressure method. The deposition temperature is 900 ° C, the deposition time is 1 h, the deposition pressure is 1500 Pa, and the flow rate of boron trichloride is 1 L h -1 , the flow rate of ammonia gas is 3L·h -1 , the flow rate of hydrogen is 10L·h -1 , the nitrogen flow rate is 10L·h -1 , to obtain a fiber preform with PyC coating / h-BN coating, that is, SiC f / (PyC / h-BN) intermediate.

[0052] (3) SiC obtained in step (2) f / (PyC / h-BN) intermediate was placed in LPVCS impregnation solution and vacuum impregnated for 12h. Take out the vacuum-impregnated intermediate and put it into a graphite mold, and carry out cross-li...

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
densityaaaaaaaaaa
bending strengthaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention discloses an interface modification method of a SiCf/SiC composite material. The method comprises the following steps: 1, producing an interface coating layer on the SiC fiber surface of a SiC fiber preform; and 2, processing by adopting a hot die pressing assisted cross-linking PIP technology with the SiC fiber preform with the interface coating layer as a reinforcement and LPVCS as a precursor to produce an interface modified SiCf/SiC composite material. The interface modification method substantially improves the interface combination of fibers and a substrate in the composite material, improves the bending strength and the fracture toughness of the composite material, reduces the porosity of the material and shortens the preparation cycle of the composite material.

Description

technical field [0001] The invention relates to the field of silicon carbide-based composite materials, in particular to a SiC f Interface modification method of SiC / SiC composites. Background technique [0002] With the development of human science and technology, how to further improve the performance of structural materials has gradually become an important breakthrough to accelerate scientific and technological progress. Due to the fatal weaknesses of ceramic materials such as high brittleness, poor reliability, and high processing difficulty, it has seriously hindered its practical application as a structural material. Fiber-reinforced ceramic matrix composites can greatly improve the brittleness of single-phase ceramic materials, absorb energy through mechanisms such as crack deflection, fiber fracture, and fiber pull-out during the fracture process, and improve the strength and toughness of the material. Excellent properties such as strength, high specific modulus, ...

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): C04B35/80C04B35/565C04B35/622
Inventor 周新贵杨备余金山王洪磊柴宇新杨会永殷刘彦
Owner NAT UNIV OF DEFENSE TECH
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