CN107827477B

CN107827477B - Based on Ti3SiC2Reaction diffusion bonding method for carbon-carbon composite material with-Al mixed powder as intermediate layer

Info

Publication number: CN107827477B
Application number: CN201711062538.5A
Authority: CN
Inventors: 贾建刚; 高昌琦; 安亮; 季根顺; 郝相忠; 杨兆庆
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2017-10-27
Filing date: 2017-10-27
Publication date: 2020-09-08
Anticipated expiration: 2037-10-27
Also published as: CN107827477A

Abstract

The invention discloses a Ti-based alloy₃SiC₂The reaction diffusion bonding method of the carbon-carbon composite material with the Al mixed powder as the middle layer comprises the following steps: mixing Al powder with Ti₃SiC₂The powder is mixed and stirred evenly according to a certain proportion to obtain Ti₃SiC₂-an Al mixed powder; the obtained Ti₃SiC₂Uniformly paving the Al mixed powder between the two cleaned C/C composite materials, wherein the loose thickness of the powder is 1 mm; will be charged with Ti₃SiC₂The C/C composite material of the-Al mixed powder intermediate layer is pressurized and insulated for 30min under the conditions that the temperature is 1450 ℃ and the pressure is 10-20Mpa under the protective atmosphere. The invention uses Ti₃SiC₂The powder is used as a main component, a proper amount of Al powder is added, and stable high-temperature high-strength connection between the C/C composite materials is realized by a solid-phase diffusion and reaction sintering method.

Description

Based on Ti3SiC2Reaction diffusion bonding method for carbon-carbon composite material with-Al mixed powder as intermediate layer

Technical Field

The invention relates to the field of material processing, in particular to a Ti-based material₃SiC₂A reaction diffusion connection method of a carbon-carbon composite material with-Al mixed powder as an intermediate layer.

Background

At present, the C/C composite material is widely applied to the fields of novel material research and development, military industry and the like, has a plurality of excellent performances such as high modulus, high strength, high temperature resistance, corrosion resistance, friction and wear resistance, low density and the like, and has important significance in effective and stable connection of the C/C composite material and the C/C composite material. The existing connection modes comprise mechanical (such as bolt) connection, active metal brazing connection, glass connection and solid phase diffusion connection, and each mode has respective advantages and disadvantages. For example, the active brazing connection has the defect that a large amount of solder permeates into a carbon/carbon matrix and cannot form a particularly strong connection surface, and the mutual diffusion of the material elements of the glass connection interface is easy to generate the defects of air holes and the like, so that the exertion of the excellent performance of the C/C composite material member is influenced.

Ti₃SiC₂The material combines the advantages of metal and ceramic, has the advantages of high yield strength, high melting point, high thermal stability and good oxidation resistance of ceramic materials, keeps high strength at high temperature, has the performance of metal, and has good electrical conductivity, thermal conductivity and high-temperature plasticity.

Disclosure of Invention

In order to solve the above problems, the present invention provides a Ti-based alloy₃SiC₂A reaction diffusion connection method of a carbon-carbon composite material with-Al mixed powder as an intermediate layer.

In order to achieve the purpose, the invention adopts the technical scheme that:

based on Ti₃SiC₂-Al mixed powder ofThe reaction diffusion connection method of the carbon-carbon composite material of the middle layer comprises the following steps:

s1, mixing Al powder with Ti₃SiC₂The powder is mixed and stirred evenly according to a certain proportion to obtain Ti₃SiC₂-an Al mixed powder;

s2, mixing the obtained Ti₃SiC₂Uniformly paving the Al mixed powder between the two cleaned C/C composite materials, wherein the loose thickness of the powder is 1 mm;

s3, adding Ti₃SiC₂And (3) pressurizing and preserving the C/C composite material of the-Al mixed powder intermediate layer for 30min under the conditions that the temperature is 1450 ℃ and the pressure is 10-20Mpa in an argon or vacuum environment.

Wherein, in the step S1, the Al powder accounts for 5-20% of the mixed powder by weight percent.

The invention has the following beneficial effects:

with Ti₃SiC₂The powder is used as a main component, a proper amount of Al powder is added, and stable high-temperature high-strength connection between the C/C composite materials is realized by a solid-phase diffusion and reaction sintering method.

Drawings

FIG. 1 shows the morphology of a C/C composite material connecting layer containing 5 wt% of Al and an EDS spectrum.

FIG. 2 is SEM morphology and EDS spectrum of C/C composite material connection layer containing 10 wt% Al.

FIG. 3 is an XRD spectrum of a sample containing 10 wt% Al raw powder and sintered at 1450 ℃.

FIG. 4 is an SEM image and an EDS spectrum of a carbon-carbon junction layer containing 20 wt% Al content.

Detailed Description

In order that the objects and advantages of the invention will be more clearly understood, the invention is further described in detail below with reference to examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the following examples, the carbon-carbon composite material used was a carbon fiber cloth impregnated carbonized laminate provided by hoechuan carbon fiber limited, gansu; ti used₃SiC₂Both the powder and the Al powder are commercially available products.

Examples

Based on Ti₃SiC₂The reaction diffusion bonding method of the carbon-carbon composite material with the Al mixed powder as the middle layer comprises the following steps:

s1, mixing Al powder with Ti₃SiC₂The powder is mixed and stirred evenly according to a certain proportion to obtain Ti₃SiC₂-Al mixed powder, wherein the Al powder accounts for 5-20% by weight;

s2, mixing Ti₃SiC₂The Al mixed powder is uniformly paved between the two cleaned C/C composite materials, and the loose thickness of the powder is about 1 mm;

s3, adding Ti₃SiC₂And (3) pressurizing and preserving the C/C composite material of the-Al mixed powder intermediate layer for 30min under the conditions that the temperature is 1450 ℃ and the pressure is 10-20Mpa in an argon or vacuum environment, and then completing the connection of the composite material.

FIG. 1 shows the morphology of a C/C composite material connecting layer containing 5 wt% of Al and an EDS spectrum. It can be seen that the thickness of the connecting layer between the composite materials is uniform, the connecting layer is combined with the interface of the substrate compactly, and no defects such as obvious holes exist between the composite materials and the substrate. The analysis by EDS shows that the Si content of the interface layer area adjacent to the matrix material is obviously higher than that of other areas, and the relative content of Al element is higher than that of the middle area, which indicates that aluminum diffuses to the matrix during diffusion bonding. The difference between the Ti, C and Si element contents in the central area and the ratio of each element in the original powder is large, which shows that under the condition of solid phase diffusion, except the diffusion and enrichment of an Al element phase interface layer, Ti is rich₃SiC₂It is no longer stable in a single phase, but rather decomposition occurs and the Si element diffuses to the vicinity of the interface.

FIG. 2 shows the morphology of the C/C composite material connecting layer containing 10 wt% of Al and an EDS spectrum. It can be seen that the connecting layer between the composite materials is uniform in thickness, and is combined with the interface of the matrix compactly, and the defects of obvious holes and the like are avoided. Similar to the interfacial layer at an Al content of 5 wt%, the interfacial layer region adjacent to the matrix material has a significantly higher Si and Al content than the intermediate region, indicating that aluminum diffuses into the matrix during diffusion bonding, as shown in FIGS. 2(b) and (c).

FIG. 3 is an XRD spectrum of a sample containing 10 wt% Al raw powder and sintered at 1450 ℃. It can be seen that the original powder contained only Ti₃SiC₂And the peaks of the two independent phases of Al prove that the raw material components are pure and have no obvious impurities. After hot-pressing sintering, Ti₃SiC₂Completely reacts with Al to generate Al₄SiC₄SiC, but still a small amount of Al is present in the elemental state. Al (Al)₄SiC₄And both the SiC phases have excellent high-temperature performance, so that the performance of the connecting layer can be improved to a certain extent by the mutual coordination of the two phases of substances. The existence of the simple substance Al promotes solid phase diffusion and sintering compactness.

FIG. 4 is an SEM image and an EDS spectrum of a carbon-carbon junction layer containing 20 wt% Al content. It can clearly be seen that the tie layer bonds well to the substrate. EDS analysis finds that Al at the joint with the matrix is up to more than 90%, and the balance is Si, which indicates that Al and Si are still enriched at the interface, but in the case that the Al element exceeds a certain amount, the enrichment phenomenon is particularly serious.

In summary, the Al powder is mixed with Ti by weight percentage of 5-20%₃SiC₂Mixing the powder, and can be used for a carbon-carbon composite solid phase diffusion interlayer; and preserving the heat at 1450 ℃ and under 10-20Mpa for 30min to obtain the uniform and compact diffusion connection joint which is well combined with the matrix.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be construed as the protection scope of the present invention.

Claims

1. Based on Ti₃SiC₂The reaction diffusion bonding method of the carbon-carbon composite material with the Al mixed powder as the middle layer is characterized by comprising the following steps of:

s1, mixing Al powder with Ti₃SiC₂The powder is mixed and stirred evenly according to a certain proportion to obtain Ti₃SiC₂-Al mixed powder, wherein the Al powder accounts for 5-20% of the mixed powder by weight;

s3, adding Ti₃SiC₂And (3) pressurizing and preserving the C/C composite material of the-Al mixed powder intermediate layer for 30min under the conditions that the temperature is 1450 ℃ and the pressure is 10-20MP a in a protective atmosphere, wherein the protective atmosphere is an argon or vacuum environment.