Method for preparing LaB6/Si-Mo gradient high-temperature anti-oxidation coating

A high-temperature anti-oxidation and coating technology, which is applied in the field of preparation of LaB6/Si-Mo gradient high-temperature anti-oxidation coatings, can solve the problems that the thickness is difficult to control artificially, it is not suitable for industrial application, and the coating thickness is uneven, so as to achieve less surface defects , Excellent high temperature oxidation resistance, low porosity effect

Active Publication Date: 2016-03-16
NORTHWESTERN POLYTECHNICAL UNIV
View PDF2 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the thickness of the coating prepared by the embedding method is difficult to control artificially, the thickness of the coating is uneven, and the surface has many pores, which easily leads to the infiltration of oxygen. When embedding large components, the requirements for the furnace are high, and the powder consumption is large. Not suitable for industrial applications

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] 1) Sand and chamfer the C / C composite material with sandpaper, clean it, and then dry it in an oven for later use.

[0023] 2) Prepare a gradient coating on the surface of the C / C composite material, first prepare the SiC inner coating to relieve the thermal expansion of the substrate and the coating, and then prepare SiC-MoSi 2 The middle layer, which alleviates the thermal adaptation problem of the inner and outer coatings, and finally prepares LaB 6 / Si-Mo coating.

[0024] Preparation method of the inner coating: Weigh 50% Si powder and 50% C powder and mix, put the mixed powder into a ball mill and dry it, put the powder into a graphite crucible and embed the cleaned C / C composite material, cover the crucible and put it into a high-temperature furnace for heat treatment at 1600°C for 1 hour, and then a SiC inner coating can be obtained on the surface of the C / C composite material.

[0025] Intermediate layer preparation method: weigh 15% MoSi 2 Powder, 65% Si p...

Embodiment 2

[0028] 1) Sand and chamfer the C / C composite material with sandpaper, clean it, and then dry it in an oven for later use.

[0029] 2) Prepare a gradient coating on the surface of the C / C composite material, first prepare the SiC inner coating to relieve the thermal expansion of the substrate and the coating, and then prepare SiC-MoSi 2 The middle layer, which alleviates the thermal adaptation problem of the inner and outer coatings, and finally prepares LaB 6 / Si-Mo coating.

[0030] Inner coating preparation method: Weigh 65% Si powder and 35% C powder and mix, put the mixed powder into a ball mill and dry it, put the powder into a graphite crucible and embed the cleaned C / C composite material, cover the crucible and put it into a high-temperature furnace for heat treatment at 1800°C for 1 hour, and then a SiC inner coating can be obtained on the surface of the C / C composite material.

[0031] Intermediate layer preparation method: weigh 20% MoSi 2 Powder, 65% Si powder, a...

Embodiment 3

[0034] 1) Sand and chamfer the C / C composite material with sandpaper, clean it, and then dry it in an oven for later use.

[0035] 2) Prepare a gradient coating on the surface of the C / C composite material, first prepare the SiC inner coating to relieve the thermal expansion of the substrate and the coating, and then prepare SiC-MoSi 2 The middle layer, which alleviates the thermal adaptation problem of the inner and outer coatings, and finally prepares LaB 6 / Si-Mo coating.

[0036] Preparation method of the inner coating: Weigh 70% Si powder and 30% C powder and mix them, put the mixed powder into a ball mill and dry it, put the powder into a graphite crucible and embed the cleaned C / C composite material, cover the crucible and put it into a high-temperature furnace for heat treatment at 2000°C for 1 hour, and then a SiC inner coating can be obtained on the surface of the C / C composite material.

[0037] Intermediate layer preparation method: weigh 35% MoSi 2 powder, 55%...

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

No PUM Login to view more

Abstract

The invention relates to a method for preparing a LaB6 / Si-Mo gradient high-temperature anti-oxidation coating. According to the method, a SiC internal coating is prepared on the surface of a C / C composite material to relieve the problem of concentrated thermal stress caused by thermal expansion coefficient difference between a matrix and the coating; the intermediate layer is a SiC-MoSi2 transition coating and serves as a transition layer of internal and external coatings, cracks, pores and other defects of the external coating generated under a high-temperature condition can be effectively reduced, the excellent high-temperature oxidation resistance of the coating can be achieved, and the resistance adaptability of the C / C composite material under high-temperature aerobic relieving condition is further improved; the LaB6 / Si-Mo coating is prepared by utilizing a plasma spraying method, so that the thickness of the coating can be accurately controlled, and the problem of uneven thickness of the coating is solved. Gradient is sequentially formed among the coatings, so that generation of thermal stress is reduced, and the binding force among the coatings is improved. Advantages of the plasma spraying method and an embedding method are combined, so that the high-temperature oxidation resistance of the coating can be greatly improved.

Description

technical field [0001] The invention belongs to the coating preparation method of C / C composite material, in particular to a kind of LaB 6 Preparation method of / Si-Mo gradient high temperature oxidation resistant coating. Background technique [0002] Carbon / carbon (C / C) composites have excellent high-temperature performance and are thermal protection materials integrating structure and function in aerospace and other fields. However, they are easily oxidized under high temperature conditions, which affects the further use of this material. C / C composite materials are mainly used in high-temperature aerobic environments, such as missile and rocket engine components with operating temperatures as high as 1700-2000°C or even higher, and the aerodynamic heating of the nose cone of the space shuttle can reach 1300-1700°C when reentry into the atmosphere, etc. . If effective anti-oxidation protection measures are not taken, pure C / C composite materials cannot exert their high-...

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): C04B41/89
CPCC04B41/009C04B41/52C04B41/89C04B41/4545C04B41/455C04B41/5059C04B41/5071C04B41/4527C04B41/507C04B35/83
Inventor 史小红王昌聪李贺军
Owner NORTHWESTERN POLYTECHNICAL 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