阅读说明：本技术 Mb2基超高温陶瓷涂层及其制备方法 (MB2Ultrahigh-temperature-based ceramic coating and preparation method thereof ) 是由 成程 其他发明人请求不公开姓名 于 2020-07-30 设计创作，主要内容包括：本发明提供MB<Sub>2</Sub>基超高温陶瓷涂层,包括超高温陶瓷本体涂层,该超高温陶瓷本体的组成为MB<Sub>2</Sub>-M<Sup>1</Sup>Si-Mo-SiC,按体积分数计,其包括40～60%MB<Sub>2</Sub>,20～40%M<Sup>1</Sup>Si,20～40%Mo和0～20%SiC；其中MB<Sub>2</Sub>包括HfB<Sub>2</Sub>和ZrB<Sub>2</Sub>,且体积比为4︰1～1︰4；M<Sup>1</Sup>Si包括MoSi<Sub>2</Sub>、CrSi<Sub>2</Sub>、ZrSi<Sub>2</Sub>和TaSi<Sub>2</Sub>中的一种或两种以上,且体积比为0～4︰0～4：1～8：0～2。还提供一种MB<Sub>2</Sub>基超高温陶瓷涂层的制备方法。本发明的陶瓷涂层耐烧蚀好、喷涂工艺性好、中高温抗氧化性能优异、结构致密且与基体强结合,本发明的方法工艺简单、涂层成分和厚度易于控制,生产效率高。(The invention provides MB 2 The ultrahigh-temperature ceramic coating comprises an ultrahigh-temperature ceramic body coating, wherein the ultrahigh-temperature ceramic body consists of MB 2 ‑M 1 Si-Mo-SiC, which comprises 40 to 60% by volume of MB 2 ，20～40%M 1 Si, 20-40% of Mo and 0-20% of SiC; wherein MB is 2 Including HfB 2 And ZrB 2 And the volume ratio is 4: 1-1: 4; m 1 Si comprises MoSi 2 、CrSi 2 、ZrSi 2 And TaSi 2 One or more than two of (1), and the volume ratio is 0-4: 1-8: 0 to 2. Also provides a MB 2 A method for preparing a base ultra-high temperature ceramic coating. The ceramic coating has the advantages of good ablation resistance, good spraying manufacturability, excellent medium-high temperature oxidation resistance, compact structure and strong combination with a matrix.)

1. MB (multimedia broadcasting)₂The ultrahigh-temperature ceramic coating is characterized by comprising an ultrahigh-temperature ceramic body coating, wherein the ultrahigh-temperature ceramic body coating comprises MB₂-M¹Si-Mo-SiC comprising, by volume fraction, 40 to 60% MB₂，20～40%M¹Si, 20-40% of Mo and 0-20% of SiC; wherein MB is₂Including HfB₂And ZrB₂And HfB₂And ZrB₂The volume ratio of (A) is 4: 1-1: 4; m¹Si comprises MoSi₂、CrSi₂、ZrSi₂And TaSi₂One or more than two of (1), and MoSi₂、CrSi₂、ZrSi₂And TaSi₂The volume ratio of (A) to (B) is 0-4: 1-8: 0 to 2.

2. The MB of claim 1₂The ultrahigh-temperature ceramic coating is characterized by further comprising a silicon-based transition layer; the composition of the silicon-based transition layer is Si-ZrB₂-SiC-Al, in volume fraction, Si, ZrB₂And the content of SiC and Al is 45-70%, 10-20%, 15-30% and 5-10% in sequence.

3. The MB according to claim 1 or 2₂The preparation method of the basic ultrahigh-temperature ceramic coating is characterized by comprising the following steps of:

(1) preparation of MB₂Base ultra-high temperature ceramic agglomerated powder;

(2) preparing a base material for spraying;

(3) preparation of MB on the surface of a substrate by supersonic plasma spraying₂A base ultra high temperature ceramic coating;

(3.1) pretreating a base material;

(3.2) preparation of MB by supersonic plasma spraying₂Ultra-high temperature ceramicCoating the body.

4. The MB of claim 3₂The preparation method of the substrate ultrahigh temperature ceramic coating is characterized by further comprising the steps of preparing a silicon-based transition layer on the surface of the substrate before the step (3.2); the silicon-based transition layer is prepared by supersonic plasma spraying, and specifically comprises the following steps: according to Si, ZrB₂Adding the SiC and the Al into the raw materials in volume fraction, performing spray granulation to obtain agglomerated composite powder, and preparing a silicon-based transition layer by adopting supersonic plasma spraying; the technological parameters of the supersonic plasma spraying are as follows: the spraying power is 35-50 kW, the main gas Ar flow rate is 120-150L/min, and the auxiliary gas H₂The flow rate is 6-10L/min, the spraying distance is 80-100 mm, the flow rate of the carrier gas Ar is 8-12L/min, and the feeding speed is 15-25 g/min.

5. The MB as claimed in claim 3 or 4₂The preparation method of the base ultra-high temperature ceramic coating is characterized by also comprising the step of preparing the MB₂Carrying out laser surface remelting treatment on the basic ultrahigh-temperature ceramic coating; the laser remelting treatment comprises the following steps: by continuous CO₂The laser system processes, the laser power is set to be 5-8 kW, and the defocusing amount adopted by the laser beam is 50-120 mm.

6. The MB as claimed in claim 3 or 4₂The preparation method of the ultrahigh-temperature ceramic coating is characterized in that the step (1) comprises the following steps: adding the raw materials according to the designed proportion of the coating, and using ZrO₂And as a grinding ball, polyvinyl alcohol or Arabic resin powder is used as a binder, slurry is prepared in a roller ball milling mode, the slurry is subjected to spray granulation, and agglomerated composite powder with the particle size of 20-80 microns is collected at an outlet.

7. The MB of claim 6₂The preparation method of the base ultra-high temperature ceramic coating is characterized by also comprising the steps of carrying out heat treatment on the agglomerated composite powder; the heat treatment is carried out in a resistance furnace, the atmosphere is argon atmosphere, and the treatment temperature is 1200-1800 ℃.

8. The MB as claimed in claim 3 or 4₂The preparation method of the base ultrahigh temperature ceramic coating is characterized in that in the step (3), the technological parameters of the supersonic plasma spraying are as follows: the spraying power is 30-50 kW, the main gas Ar flow rate is 60-250L/min, and the auxiliary gas H₂The flow rate is 4-10L/min, the spraying distance is 70-120 mm, the flow rate of the carrier gas Ar is 8-12L/min, and the feeding speed is 15-25 g/min.

9. The MB as claimed in claim 3 or 4₂The preparation method of the ultrahigh-temperature ceramic coating is characterized in that in the step (2), a continuous fiber reinforced composite material, a porous material or a high-temperature alloy is selected as a base material for spraying; the continuous fiber reinforced composite material comprises C/C, C_f/SiC and C_fthe/MC-SiC, wherein M is Zr or Hf; the porous material substrate comprises a foam material of silicon nitride, silicon carbide and carbon, and carbon and Al₂O₃、SiO₂-Al₂O₃And aerogels of Si-C-O and composites thereof; the superalloys include nickel-based superalloys and molybdenum-based superalloys.

10. The MB of claim 9₂The preparation method of the ultrahigh-temperature-based ceramic coating is characterized in that in the step (3.1), if the continuous fiber reinforced composite material and the high-temperature alloy are selected as the base materials, the base materials are cleaned by absolute ethyl alcohol, and after drying, surface sand blasting and roughening treatment are carried out; if the porous material is selected as the base material, the porous material is cleaned by absolute ethyl alcohol and then dried for standby.

Technical Field

The invention belongs to the field of ceramic coatings, and particularly relates to an MB coating₂A base ultra-high temperature ceramic coating and a preparation method thereof.

Background

The hypersonic weapon system comprises a ballistic missile, an air-breathing hypersonic aircraft, a boosting gliding weapon system, a reusable aerospace plane and the like. Hypersonic weapons systems are subject to harsh pneumatic heating phenomena and gas-fired thermal environments, e.g., temperatures in excess of 2000 ℃ and heat flows above 10 MW/m²New and higher requirements are put forward on the performance and the preparation technology of the thermal protection material. Usually requiring heat shielding materialHas excellent high temperature performance, ablation resistance, oxidation resistance, mechanical performance, thermophysical performance and the like. The coating on the surface of the material is an effective method for improving the performance of the material, the preparation process of the surface coating is various, and the composition, the structure and the performance of the coating are easy to regulate and control, so that the method becomes the simplest and most practical material design and development means. Ultra-high temperature ceramics (UHTC) refers to carbides, borides, and nitrides of transition metals having melting points in excess of 3000 deg.C, such as ZrB₂、HfB₂TaC, HfC, NbC, ZrC, HfN, etc. MB (multimedia broadcasting)₂(M = Zr, Hf, Ta, etc.) ultrahigh-temperature ceramic has many excellent performances of high melting point, good thermal stability, high thermal conductivity, good mechanical property, oxidation resistance, ablation resistance, etc., and MB is designed and prepared₂The ultrahigh-temperature ceramic coating is expected to meet the requirements of the ultrahigh-temperature thermal protection material on the comprehensive performance of the material.

Various ultrahigh temperature ceramic coating systems and techniques for their preparation have been developed. The coating systems currently being developed include ZrB₂-SiC、ZrC-SiC、ZrB₂-MoSi_2、ZrC-Al₂O₃Etc. the ablation performance, coating compactness and bonding strength of the current material systems need to be improved, and in addition, the coating thickness is lower and is generally less than 500 mu m. In the aspect of preparation methods, chemical vapor deposition, embedding method, slurry coating method, thermal spraying method and the like are mainly used. Chemical Vapor Deposition (CVD) has the defects of low deposition efficiency, high production cost and the like, and the coating has single component and cannot prepare a multi-component composite ceramic coating. The coating prepared by the embedding method has poor uniformity and difficult thickness control. The coating prepared by the slurry brushing process has low density, poor thermal shock resistance and low bonding strength.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide the MB with good ablation resistance, good spraying manufacturability, excellent medium-high temperature oxidation resistance, compact structure and strong combination with a matrix₂(M = Zr, Hf) -based ultra-high temperature ceramic coating and also provides an MB coating with simple process, easily controlled coating components and thickness and high production efficiency₂(M = Zr, Hf) based ultra-high temperature ceramic coating preparation method.

In order to solve the technical problems, the invention adopts the following technical scheme:

MB (multimedia broadcasting)₂The ultrahigh-temperature ceramic coating comprises an ultrahigh-temperature ceramic body coating, wherein the ultrahigh-temperature ceramic body consists of MB₂-M¹Si-Mo-SiC comprising, by volume fraction, 40 to 60% MB₂，20～40%M¹Si, 20-40% of Mo and 0-20% of SiC; wherein MB is₂Including HfB₂And ZrB₂And HfB₂And ZrB₂The volume ratio of (A) is 4: 1-1: 4; m¹Si comprises MoSi₂、CrSi₂、ZrSi₂And TaSi₂One or more than two of (1), and MoSi₂、CrSi₂、ZrSi₂And TaSi₂The volume ratio of (A) to (B) is 0-4: 1-8: 0 to 2.

The above MB₂A substrate ultra-high temperature ceramic coating, preferably, the ultra-high temperature ceramic coating further comprises a silicon-based transition layer; the composition of the silicon-based transition layer is Si-ZrB₂-SiC-Al, in volume fraction, Si, ZrB₂The SiC and Al contents are 45-70%, 10-20%, 15-30% and 5-10% in sequence.

As a general inventive concept, there is also provided an MB₂The preparation method of the ultrahigh-temperature ceramic coating comprises the following steps:

(1) preparation of MB₂Base ultra-high temperature ceramic agglomerated powder;

(2) preparing a base material for spraying;

(3) preparation of MB on the surface of a substrate by supersonic plasma spraying₂A base ultra high temperature ceramic coating;

(3.1) pretreating a base material;

(3.2) preparation of MB by supersonic plasma spraying₂A substrate ultra high temperature ceramic coating body.

The above MB₂The preparation method of the substrate ultrahigh temperature ceramic coating preferably further comprises the steps of preparing a silicon-based transition layer on the surface of the substrate before the step (3.2); the silicon-based transition layer is prepared by supersonic plasma spraying, and specifically comprises the following steps: according to Si, ZrB₂Adding the SiC and the Al into the raw materials according to the volume fraction,firstly, obtaining agglomerated composite powder through spray granulation, and then preparing a silicon-based transition layer by adopting supersonic plasma spraying; the technological parameters of the supersonic plasma spraying are as follows: the spraying power is 35-50 kW, the main gas Ar flow rate is 120-150L/min, and the auxiliary gas H₂The flow rate is 6-10L/min, the spraying distance is 80-100 mm, the flow rate of the carrier gas Ar is 8-12L/min, and the feeding speed is 15-25 g/min.

The above MB₂The preparation method of the ultrahigh-temperature-based ceramic coating preferably also comprises the step of preparing the MB₂Carrying out laser surface remelting treatment on the basic ultrahigh-temperature ceramic coating; the laser remelting treatment comprises the following steps: by continuous CO₂The laser system processes, the laser power is set to be 5-8 kW, and the defocusing amount adopted by the laser beam is 50-120 mm.

The above MB₂The preparation method of the ultrahigh-temperature-based ceramic coating preferably comprises the following steps of (1): adding the raw materials according to the designed proportion of the coating, and using ZrO₂And as a grinding ball, polyvinyl alcohol or Arabic resin powder is used as a binder, slurry is prepared in a roller ball milling mode, the slurry is subjected to spray granulation, and agglomerated composite powder with the particle size of 20-80 microns is collected at an outlet.

The above MB₂The preparation method of the ultrahigh-temperature ceramic coating preferably further comprises the steps of carrying out heat treatment on the agglomerated composite powder; the heat treatment is carried out in a resistance furnace, the atmosphere is argon atmosphere, and the treatment temperature is 1200-1800 ℃.

The above MB₂The preparation method of the basic ultrahigh-temperature ceramic coating preferably comprises the following process parameters of the supersonic plasma spraying in the step (3): the spraying power is 30-50 kW, the main gas Ar flow rate is 60-250L/min, and the auxiliary gas H₂The flow rate is 4-10L/min, the spraying distance is 70-120 mm, the flow rate of the carrier gas Ar is 8-12L/min, and the feeding speed is 15-25 g/min.

The above MB₂The preparation method of the ultrahigh-temperature ceramic coating preferably selects the continuous fiber reinforced composite material, the porous material or the high-temperature alloy as the base material for spraying in the step (2); the continuous fiber reinforced composite material comprises C/C, C_f/SiC and C_f/MC-SiC, wherein M is Zr or Hf; the porous material substrate comprises a foam material of silicon nitride, silicon carbide and carbon, and carbon and Al₂O₃、SiO₂-Al₂O₃And aerogels of Si-C-O and composites thereof; the superalloys include nickel-based superalloys and molybdenum-based superalloys.

The above MB₂Preferably, in the step (3.1), if the continuous fiber reinforced composite material and the high-temperature alloy are selected as the base material, the base material is cleaned by absolute ethyl alcohol, and is subjected to surface sand blasting and coarsening treatment after being dried; if the porous material is selected as the base material, the porous material is cleaned by absolute ethyl alcohol and then dried for standby.

Compared with the prior art, the invention has the advantages that:

1. MB of the invention₂(M = Zr, Hf) based ultra high temperature ceramic coating can significantly improve C/C, C_fThe coating has compact structure and strong bonding force with a matrix.

2. The silicon-based transition layer can effectively solve the problems of base materials (suitable for composite materials and porous material base materials, and does not comprise high-temperature alloy) and surface structure layers (MB)₂(M = Zr, Hf) based ultra high temperature ceramic coating) and improves the bonding strength of the structural layers. Compared with the traditional embedding and chemical deposition process, the thermal spraying process has the advantages of higher preparation efficiency and easier adjustment of components, thickness and structure. The silicon-based transition layer has high density, and can continuously provide oxidation resistance protection for the base material when the surface structure layer is damaged.

3. The invention prepares MB by adopting supersonic plasma spraying and laser surface remelting treatment₂The (M = Zr, Hf) base ultrahigh-temperature ceramic coating can be used for preparing the multi-element composite ceramic coating with good quality and high bonding strength with the base body, and the coating thickness is easy to regulate and control, the production efficiency is high, the influence of the technological process on the base material is small, and the adaptability is good. In the invention, the laser surface remelting post-treatment can eliminate the prepared MB₂Ultra high temperature ceramic coatingThe layered structure of the layer can improve the chemical stability of the ceramic coating. Furthermore, the inventors have found that the preparation of MB is carried out by supersonic plasma spraying₂When the ultrahigh-temperature ceramic coating is used, the in-situ sintering phenomenon only partially occurs, the sintering is incomplete, the density and the bonding strength can still be continuously improved, the bonding strength of the coating can be improved, the surface openings are closed, the porosity and the surface roughness are reduced, the density of the coating is improved, the microhardness of the coating is improved, and the oxidation resistance and the ablation resistance of the coating are improved by carrying out laser remelting after the ultrasonic plasma spraying.

4. Preparation of MB by supersonic plasma spraying combined with post-treatment₂The (M = Zr, Hf) based ultrahigh-temperature ceramic coating is particularly suitable for preparing a multi-element composite ceramic coating, the coating thickness is easy to regulate and control, the production efficiency is high, the coating performance is good, and the bonding strength with a base material is high. In addition, the technological process has small influence on the base material and good adaptability.

Drawings

FIG. 1 shows a graph represented by the formula C in example 1 of the present invention_fSpraying MB on/SiC composite material as base material₂Photograph of polished cross section of (M = Zr, Hf) based ultra high temperature ceramic coating.

FIG. 2 shows spray coating of MB onto a silicon carbide foam substrate according to example 3 of the present invention₂Surface electron microscope photographs of (M = Zr, Hf) based ultra high temperature ceramic coatings.

Detailed Description

The invention provides a MB (multimedia broadcasting)₂The ultrahigh-temperature ceramic coating comprises an ultrahigh-temperature ceramic body coating, wherein the ultrahigh-temperature ceramic body comprises MB₂-M¹Si-Mo-SiC comprising, by volume fraction, 40 to 60% MB₂，20～40%M¹Si, 20-40% of Mo and 0-20% of SiC; wherein MB is₂Including HfB₂And ZrB₂And HfB₂And ZrB₂The volume ratio of (A) is 4: 1-1: 4; m¹Si comprises MoSi₂、CrSi₂、ZrSi₂And TaSi₂One or more than two of (1), and MoSi₂、CrSi₂、ZrSi₂And TaSi₂The volume ratio of (A) is 0-4: 1-8: 0-2.

In the ultra-high temperature ceramic body, MB₂The volume fraction of (A) is preferably 50-60%; m¹The volume fraction of Si is preferably 20-25%; the volume fraction of Mo is preferably 20-25%; the volume fraction of SiC is preferably 0-10%; m¹Si preferably comprises MoSi₂、CrSi₂、ZrSi₂And TaSi₂And MoSi₂、CrSi₂、ZrSi₂And TaSi₂The volume ratio of (A) is preferably 1-2: 1-3: 1-2.

The ultrahigh-temperature ceramic coating provided by the invention adopts a continuous fiber reinforced composite material, a porous material or a high-temperature alloy as a base material for spraying; the continuous fiber reinforced composite material comprises C/C, C_f/SiC、C_f/MC-SiC (M = Zr, Hf), etc.; the porous material substrate comprises foam materials such as silicon nitride, silicon carbide and carbon, carbon and Al₂O₃、SiO₂-Al₂O₃And aerogels and composites thereof such as Si-C-O; superalloys include nickel-based superalloys and molybdenum-based superalloys and the like.

For the matrix which is a non-metallic material such as a composite material or a porous material, the ultrahigh-temperature ceramic coating also comprises a silicon-based transition layer; the composition of the silicon-based transition layer is Si-ZrB₂-SiC-Al, in volume fraction, Si, ZrB₂And the SiC and the Al are 45-70%, 10-20%, 15-30% and 5-10% in sequence. This silica-based transition layer effectively solves the thermophysical properties adaptation difficult problem of substrate and coating body, improves the bonding strength of structural layer, and the density is high, when surface structure layer suffers destruction, can continue to provide anti-oxidant protection for the substrate.

The invention also provides an MB₂The preparation method of the ultrahigh-temperature ceramic coating comprises the following steps:

(1) preparation of MB₂Base ultra-high temperature ceramic agglomerated powder;

(2) preparing a base material for spraying;

(3) preparation of MB on the surface of a substrate by supersonic plasma spraying₂A base ultra high temperature ceramic coating;

(3.1) pretreating a base material;

(3.2) usePreparation of MB by supersonic plasma spraying₂A substrate ultra high temperature ceramic coating body.

In the scheme, the MB is prepared by adopting supersonic plasma spraying optionally₂After the body is coated by the ultrahigh-temperature ceramic, the surface can be cleaned.

Preferably, before the step (3.2), a silicon-based transition layer is prepared on the surface of the substrate; the silicon-based transition layer is prepared by supersonic plasma spraying, and specifically comprises the following steps: according to Si, ZrB₂Adding the SiC and the Al into the raw materials in volume fraction, performing spray granulation to obtain agglomerated composite powder, and preparing a silicon-based transition layer by adopting supersonic plasma spraying; the technological parameters of the supersonic plasma spraying are as follows: spraying power is 35-50 kW, main gas Ar flow rate is 120-150L/min, and auxiliary gas H₂The flow rate is 6-10L/min, the spraying distance is 80-100 mm, the flow rate of carrier gas Ar is 8-12L/min, and the feeding speed is 15-25 g/min.

Preferably, it also comprises the preparation of MB₂The laser surface remelting treatment of the ultrahigh-temperature ceramic coating can eliminate the prepared MB₂The layered structure form of the ultrahigh-temperature ceramic coating can improve the chemical stability of the ceramic coating. Furthermore, the inventors have found that MB is produced by supersonic plasma spraying₂When the ultrahigh-temperature ceramic coating is used, the in-situ sintering phenomenon only partially occurs, the reaction is incomplete, the density and the bonding strength can still be continuously improved, and the problems can be solved by carrying out laser remelting after the supersonic plasma spraying; preferably, the laser remelting treatment comprises: by continuous CO₂The laser system processes, the laser power is set to be 5-8 kW, and the defocusing amount adopted by the laser beam is 50-120 mm.

The step (1) comprises the following steps: adding the raw materials according to the designed proportion of the coating, and using ZrO₂As grinding balls, polyvinyl alcohol or Arabic resin powder is used as a binder, slurry is prepared in a roller ball milling mode, the slurry is subjected to spray granulation, and agglomerated composite powder with the particle size of 20-80 microns is collected at an outlet; the dosage of the adhesive is preferably 0.5-2.5% of the total mass of the raw materials. Further comprises heat treating the agglomerated composite powder; the heat treatment is carried out in a resistance furnaceThe process is carried out in an argon atmosphere at the treatment temperature of 1200-1800 ℃, so that the compactness of the agglomerated powder can be improved and the spraying process performance of the agglomerated powder can be further improved.

Preferably, in the step (3), the process parameters of the supersonic plasma spraying are preferably as follows: spraying power is 30-50 kW, main gas Ar flow rate is 60-250L/min, and auxiliary gas H₂The flow rate is 4-10L/min, the spraying distance is 70-120 mm, the flow rate of carrier gas Ar is 8-12L/min, and the feeding speed is 15-25 g/min.

In the step (2), a continuous fiber reinforced composite material, a porous material or a high-temperature alloy is selected as a base material for spraying; the continuous fiber reinforced composite material comprises C/C, C_f/SiC、C_f/MC-SiC (M = Zr, Hf), etc.; the porous material substrate comprises foam materials such as silicon nitride, silicon carbide and carbon, carbon and Al₂O₃、SiO₂-Al₂O₃And aerogels and composites thereof such as Si-C-O; the high-temperature alloy comprises nickel-based high-temperature alloy, molybdenum-based high-temperature alloy and the like.

Preferably, in the step (3.1), if the continuous fiber reinforced composite material and the high-temperature alloy are selected as the base material, the base material is cleaned by absolute ethyl alcohol, and after drying, surface sand blasting roughening treatment is performed; if the porous material is selected as the base material, the porous material is cleaned by absolute ethyl alcohol and then dried for later use, so that the interface combination is improved.

The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention.