CN110373628B - Refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and preparation method thereof - Google Patents
Refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and preparation method thereof Download PDFInfo
- Publication number
- CN110373628B CN110373628B CN201910790625.5A CN201910790625A CN110373628B CN 110373628 B CN110373628 B CN 110373628B CN 201910790625 A CN201910790625 A CN 201910790625A CN 110373628 B CN110373628 B CN 110373628B
- Authority
- CN
- China
- Prior art keywords
- temperature
- refractory metal
- diffusion barrier
- slurry
- graphene
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C12/00—Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
The invention discloses an in-situ reaction self-generated high-temperature diffusion barrier on the surface of refractory metal, which is positioned between the refractory metal and a high-temperature protection coating of a sintered silicide coated on the surface of the refractory metal and takes SiC as a main phase; the invention also discloses a preparation method of the in-situ reaction self-generated high-temperature diffusion barrier on the surface of the refractory metal, and the method is characterized in that graphene slurry or graphene oxide slurry and silicide composite suspension slurry are sequentially pre-arranged on the surface of the pretreated refractory metal matrix and are sintered to obtain the in-situ reaction self-generated high-temperature diffusion barrier. The high-temperature diffusion barrier reduces the high-temperature mutual diffusion rate between the high-temperature protective coating and the refractory metal matrix, ensures the high-temperature oxidation resistance of the high-temperature protective coating and prolongs the high-temperature service life of the high-temperature protective coating; the invention prepares the high-temperature diffusion barrier by in-situ reaction, improves the interface compatibility and ensures that the refractory metal-diffusion barrier-high-temperature protective coating has good thermal cycle resistance and thermal shock resistance.
Description
Technical Field
The invention belongs to the technical field of refractory metal high-temperature protection, and particularly relates to a refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and a preparation method thereof.
Background
Refractory metals have excellent high temperature strength and toughness and good processability and are widely used in the aerospace and atomic energy industries. However, the application of refractory alloys in ultra-high temperature oxidation environments presents oxidation resistance difficulties. The ultrahigh temperature protective coating is applied to the surface of the refractory metal, so that the high temperature oxidation resistance of the refractory metal can be obviously improved, and the high temperature service life of the refractory metal is prolonged. The most widely used high temperature protective coatings for refractory metal surfaces are silicide coatings, aluminide coatings, and noble metal coatings.
However, the chemical compositions of the coating and the refractory metal substrate are significantly different, the chemical activities of all components in the coating and the substrate are different, and mutual diffusion cannot be avoided between the coating and the substrate in the service process. On one hand, the mutual diffusion causes the large consumption of high-temperature oxidation resistant effective components (Si, Al, Ir and the like) in the coating, the service life of the coating is greatly shortened, and in addition, matrix elements are diffused into the coating to cause the change of chemical components of the coating, so that the high-temperature oxidation resistance of the coating is reduced; on the other hand, interface diffusion reaction can occur between the coating and some components in the matrix to generate a brittle intermetallic compound phase or a topological close-packed phase, so that a harmful phase region is formed between the coating and the matrix, the generation of precipitated phases not only consumes solid solution strengthening elements of the refractory metal matrix and weakens the solid solution strengthening effect of the solid solution elements, but also the precipitated phases are often the origin of cracks and the rapid propagation channel of the cracks, and the creep rupture life of the refractory metal matrix is obviously reduced.
Therefore, inhibiting interdiffusion and high temperature interfacial reactions between the coating and the refractory metal substrate becomes a key to extending the high temperature service life of the refractory metal.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a refractory metal surface in-situ reaction self-generated high temperature diffusion barrier in view of the above-mentioned deficiencies of the prior art. The in-situ reaction self-generated high-temperature diffusion barrier obviously reduces the high-temperature mutual diffusion rate between the high-temperature protective coating and the refractory metal, avoids the consumption of high-temperature oxidation effective components in the high-temperature protective coating, ensures the high-temperature oxidation resistance of the high-temperature protective coating when elements in the refractory metal enter the coating, and obviously prolongs the high-temperature service life of the high-temperature protective coating.
In order to solve the technical problems, the invention adopts the technical scheme that: the in-situ reaction self-generated high-temperature diffusion barrier on the surface of the refractory metal is characterized in that the in-situ reaction self-generated high-temperature diffusion barrier is positioned between the refractory metal and a high-temperature protective coating coated on the surface of the refractory metal, SiC generated by a high-temperature chemical reaction between Si and graphene or graphene oxide is taken as a main phase, and the thickness of the in-situ reaction self-generated high-temperature diffusion barrier is 0.5-10 mu m; the high-temperature protective coating is a fused silicide coating, and the high-temperature diffusion barrier can inhibit or slow down interfacial mutual diffusion reaction between the refractory metal and the high-temperature protective coating at the temperature below 2000 ℃.
According to the invention, by utilizing the high-temperature interface reaction between Si element in the most common high-temperature protective coating-sintered silicide coating and graphene oxide or graphene, an in-situ reaction self-generated high-temperature diffusion barrier taking SiC as a main phase is introduced between a refractory metal matrix and the high-temperature protective coating coated on the surface of the refractory metal matrix, the melting point of SiC is as high as 2700 ℃, the crystal structure (β -SiC) is compact, and has excellent high-temperature structure and chemical stability, and the SiC is a linear compound, so that the concentration of lattice defects in the crystal structure is low, and the diffusion coefficient of Si element in SiC is extremely low.
The refractory metal surface in-situ reaction self-generation high-temperature diffusion barrier is characterized in that the refractory metal is Nb alloy, Mo or Mo alloy, W or W alloy or Ta alloy. The refractory metal has excellent high-temperature mechanical property and good room-temperature processing property, and can be used as a high-temperature structural material for long-time service after a high-temperature protective coating is applied.
In addition, the invention also provides a preparation method of the refractory metal surface in-situ reaction self-generation high-temperature diffusion barrier, which is characterized by comprising the following steps:
step one, sequentially polishing, sand blasting, acid washing and degreasing the surface of the refractory metal to obtain the pretreated refractory metal;
step two, mixing graphene or graphene oxide with a dispersing agent, and then placing the mixture in a ball mill for ball milling and uniformly mixing to obtain graphene slurry or graphene oxide slurry; the volume of the dispersing agent is 10-30 times of the mass of graphene or graphene oxide, wherein the unit of the volume is mL, and the unit of the mass is g;
thirdly, presetting the graphene slurry or the graphene oxide slurry obtained in the second step on the surface of the refractory metal pretreated in the first step by adopting a pneumatic spraying method, then drying, and obtaining a slurry preset layer on the surface of the refractory metal; the drying temperature is 40-80 ℃ and the drying time is 30-120 min;
step four, uniformly mixing the raw material powder for preparing the fused silicide coating with a dispersing agent to obtain silicide composite suspension slurry;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of the refractory metal obtained in the step three, drying the slurry to obtain a silicide preset layer on the surface of the refractory metal, then placing the silicide preset layer in a vacuum sintering furnace, and keeping the vacuum degree of 7 multiplied by 10-3Pa～2.0×10-2Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a high-temperature protective coating on the surface of the refractory metal and an in-situ reaction self-generated high-temperature diffusion barrier between the refractory metal and the high-temperature protective coating; the specific process of the high-temperature sintering is as follows: firstly heating to 700-900 ℃ at the speed of 10-30 ℃/min, preserving the heat for 30-120 min, then heating to 1450-1550 ℃ at the speed of 10-15 ℃/min, preserving the heat for 30-90 min.
According to the method, the SiC high-temperature diffusion barrier is formed by in-situ reaction and self-generation between the refractory metal and the outer-layer high-temperature protective coating through the chemical reaction between the graphene or the graphene oxide and Si, and compared with a metal/ceramic artificial interface formed by directly preparing the ceramic diffusion barrier between the refractory metal and the outer-layer high-temperature protective coating in the prior art, the interfaces formed between the refractory metal substrate, the SiC high-temperature diffusion barrier and the outer-layer high-temperature protective coating are all in-situ reaction and self-generation interfaces, so that the diffusion barrier/substrate and the diffusion barrier/coating interface are prevented from being formed due to the difference of the types and the component structures of the substrate and the high-temperature protective coating, better interface compatibility is achieved, the stress level of the refractory metal substrate/SiC diffusion barrier/silicide coating interface under the conditions of coating preparation and hot and cold service is reduced, and the refractory metal-diffusion barrier-high-temperature protective coating system has good Seismic performance.
The method is characterized in that in the step one, the sand used for sand blasting is corundum sand, glass beads or zirconia sand, the sand blasting pressure is 0.2 MPa-0.8 MPa, and the sand blasting time is 2 min-8 min; the acid solution used for pickling is formed by mixing hydrofluoric acid solution and concentrated nitric acid solution according to the volume ratio of (6-7) to (3-4), the mass concentration of the hydrofluoric acid solution is 40% -60%, the mass concentration of the concentrated nitric acid solution is 65% -68%, and the pickling time is 1-5 min. The oxygen absorption layer on the surface of the refractory metal is further removed by adopting the pretreatment process, and meanwhile, the surface roughness of the refractory metal is enhanced, so that the diffusion barrier and a metal matrix can form good interface combination.
The method is characterized in that the dispersant mixed with the graphene oxide in the second step is distilled water or absolute ethyl alcohol, and the dispersant mixed with the graphene is formed by mixing varnish and ethyl acetate according to the volume ratio of (1-2) to (3-4). Graphene oxide is dissolved in water, can be smoothly dissolved by using water or absolute ethyl alcohol as a solvent, and is not dissolved in water, and the dissolution and dispersion of graphene are promoted by selecting a mixed solution of varnish and ethyl acetate as a dispersing agent.
The method is characterized in that in the second step, the graphene slurry or graphene oxide slurry contains Si powder, the particle size of the Si powder is not greater than 1 μm, and the atomic percentage of graphene in the graphene slurry or graphene oxide in the graphene oxide slurry to Si is 1: (0 to 1). The silicon powder with the small particle size is beneficial to the rapid and sufficient in-situ reaction and self-generation, and the atomic percentage is beneficial to the sufficient and complete reaction of graphene or graphene oxide and Si, and simultaneously forms good interface combination with a silicide coating.
The method is characterized in that the drying temperature of the silicide slurry preset layer obtained in the step five is 40-200 ℃, and the drying time is 0.5-8 h. The drying conditions are favorable for obtaining the silicide slurry preset layer with low water content and the subsequent high-temperature sintering process.
Compared with the prior art, the invention has the following advantages:
1. according to the invention, the in-situ reaction self-generated high-temperature diffusion barrier is introduced between the refractory metal matrix and the high-temperature protective coating coated on the surface of the refractory metal matrix, so that the high-temperature mutual diffusion rate between the high-temperature protective coating and the refractory metal matrix is remarkably reduced, the consumption of high-temperature oxidation resistant effective components in the high-temperature protective coating is avoided, elements in the refractory metal matrix enter the coating, the high-temperature oxidation resistance of the high-temperature protective coating is ensured, and the high-temperature service life of the high-temperature protective coating is remarkably prolonged.
2. The melting point of the in-situ reaction autogenous diffusion barrier main phase SiC is as high as 2700 ℃, the service temperature of the diffusion barrier is high, the crystal structure (β -SiC) of the SiC is compact, the SiC has excellent high-temperature structure and chemical stability, meanwhile, the SiC is a linear compound, the concentration of lattice defects in the crystal structure is low, so that the diffusion coefficient of Si element in the high-temperature protective coating, namely the melting silicide coating, in the SiC is extremely low, the diffusion resistance of the melting silicide coating is improved, and the high-temperature oxidation resistance of the melting silicide coating is improved.
3. Compared with the prior art, the SiC high-temperature diffusion barrier is formed in situ reaction between the refractory metal and the outer high-temperature protective coating through the chemical reaction between the graphene or the graphene oxide and the high-temperature protective coating Si, so that the diffusion barrier/matrix and the diffusion barrier/coating interface are prevented from being formed due to the difference of the types and the component structures of the matrix and the high-temperature protective coating, the interface compatibility is better, the stress level of the refractory metal matrix/SiC diffusion barrier/silicide coating interface under the high-temperature protective coating preparation and the cold and hot service working conditions is reduced, and the refractory metal-diffusion barrier-high-temperature protective coating system has good thermal cycle resistance and thermal shock resistance.
4. The thermal expansion coefficient of the in-situ self-generated SiC high-temperature diffusion barrier is close to that of refractory metals and a high-temperature protective coating-fused silicide coating, and the thermal stress of the high-temperature protective coating/diffusion barrier/matrix interface is small under the working condition of cold and hot circulation service, so that the anti-stripping performance of the high-temperature protective coating is enhanced.
The technical solution of the present invention is further described in detail by examples below.
Drawings
Fig. 1 is a schematic structural view of a refractory metal having a slurry pre-deposition layer and a silicide pre-deposition layer disposed on the surface thereof according to the present invention.
FIG. 2 is a schematic structural diagram of a refractory metal with an in-situ reaction self-generated high-temperature diffusion barrier and a high-temperature protective coating formed on the surface thereof according to the present invention.
Detailed Description
As shown in fig. 1, the refractory metals having the slurry pre-set layer and the silicide pre-set layer on the surfaces thereof in embodiments 1 to 4 of the present invention have the following structures: a slurry preset layer is arranged on the surface of the refractory metal, and a silicide preset layer is arranged on the surface of the slurry preset layer; after high-temperature sintering, the structure is converted into the structure of the refractory metal with the surface formed with the in-situ reaction self-generated high-temperature diffusion barrier and the high-temperature protective coating in the figure 2, and the structure is as follows: the silicide preset layer forms a fused silicide coating, refractory metal and graphene oxide or graphene in the slurry preset layer are subjected to high-temperature reaction to generate a small amount of metal carbide, and Si element in the fused silicide coating and graphene oxide or graphene in the slurry preset layer are subjected to high-temperature interface reaction to form an in-situ reaction self-generated high-temperature diffusion barrier taking SiC as a main phase.
Example 1
The Ta12W alloy surface in-situ reaction self-generation high-temperature diffusion barrier of the embodiment is located between a Ta12W alloy and a Si-Cr-Ti-Zr high-temperature protection coating coated on the Ta12W alloy surface, SiC generated by high-temperature chemical reaction between Si and graphene oxide is used as a main phase, and the thickness of the in-situ reaction self-generation high-temperature diffusion barrier is 10 μm.
The preparation method of the Ta12W alloy surface in-situ reaction self-generated high-temperature diffusion barrier of the embodiment comprises the following steps:
step one, adopting 600#Grinding the surface of the Ta12W alloy by using SiC sand paper, then carrying out sand blasting and acid washing, and then soaking in acetone for degreasing to obtain the Ta12W alloyA pretreated Ta12W alloy; the sand adopted by the sand blasting is corundum sand, the pressure of the sand blasting is 0.8MPa, and the time of the sand blasting is 8 min; the acid solution used for pickling is formed by mixing a hydrofluoric acid solution and a concentrated nitric acid solution according to a volume ratio of 7:3, the mass concentration of the hydrofluoric acid solution is 40%, the mass concentration of the concentrated nitric acid solution is 65%, and the pickling time is 5 min;
step two, mixing graphene oxide with distilled water, placing the mixture in a ball mill, and carrying out ball milling and uniformly mixing for 120min under the condition that the rotating speed is 320 revolutions per minute to obtain graphene oxide slurry; the volume of the distilled water is 30 times of the mass of the graphene oxide, wherein the volume is mL, and the mass is g;
thirdly, presetting the graphene oxide slurry obtained in the second step on the surface of the pretreated Ta12W alloy in the first step by adopting a pneumatic spraying method, then drying, and obtaining a slurry preset layer on the surface of the Ta12W alloy; the drying temperature is 80 ℃, and the drying time is 120 min;
step four, uniformly mixing the raw material powder for preparing the Si-Cr-Ti-Zr sintered silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of the Ta12W alloy obtained in the step three, drying for 8 hours at 40 ℃, obtaining the silicide preset layer on the surface of the Ta12W alloy, then placing the silicide preset layer in a vacuum sintering furnace, and controlling the vacuum degree to be 2.0 multiplied by 10-2Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a Si-Cr-Ti-Zr high-temperature protective coating with the thickness of 125 mu m and an in-situ reaction self-generated high-temperature diffusion barrier with the thickness of 10 mu m between the Ta12W alloy and the Si-Cr-Ti-Zr high-temperature protective coating on the surface of the refractory metal; the specific process of the high-temperature sintering is as follows: heating to 700 deg.C at a speed of 10 deg.C/min, maintaining for 120min, heating to 1550 deg.C at a speed of 15 deg.C/min, and maintaining for 90 min.
Through detection, compared with a Si-Cr-Ti-Zr high-temperature protective coating which is not applied with a high-temperature diffusion barrier with SiC as a main phase, the in-situ reaction self-generation high-temperature diffusion barrier of the embodiment can obviously slow down the interface diffusion reaction between the Ta12W alloy and the Si-Cr-Ti-Zr high-temperature protective coating at the outer layer below 2000 ℃, and the constant-temperature oxidation resistance life of the Si-Cr-Ti-Zr high-temperature protective coating at 2000 ℃ is obviously prolonged.
Example 2
The Nb521 alloy surface in-situ reaction self-generated high-temperature diffusion barrier of the embodiment is located between the Nb521 alloy and the Si-Mo-Zr high-temperature protective coating coated on the Nb521 alloy surface, and takes SiC generated by a high-temperature chemical reaction between Si and graphene as a main phase, and the thickness of the in-situ reaction self-generated high-temperature diffusion barrier is 6 μm.
The preparation method of the Nb521 alloy surface in-situ reaction self-generated high-temperature diffusion barrier of the embodiment includes the following steps:
step one, adopting 600#Polishing the surface of the Nb521 alloy by using SiC sand paper, then performing sand blasting and acid pickling, and then immersing the Nb521 alloy into acetone for degreasing to obtain a pretreated Nb521 alloy; the sand adopted by the sand blasting is zirconia sand, the pressure of the sand blasting is 0.6MPa, and the time of the sand blasting is 4 min; the acid solution used for pickling is formed by mixing hydrofluoric acid solution and concentrated nitric acid solution according to the volume ratio of 6:4, the mass concentration of the hydrofluoric acid solution is 60%, the mass concentration of the concentrated nitric acid solution is 68%, and the pickling time is 3 min;
step two, mixing graphene and a dispersing agent, then placing the mixture in a ball mill, and carrying out ball milling and uniformly mixing for 240min under the condition that the rotating speed is 350 revolutions per minute to obtain graphene slurry; the dispersing agent is formed by mixing varnish and ethyl acetate according to the volume ratio of 1:4, the volume of the dispersing agent is 10 times of the mass of graphene, wherein the unit of the volume is mL, and the unit of the mass is g;
step three, presetting the graphene slurry obtained in the step two on the surface of the Nb521 alloy pretreated in the step one by adopting a pneumatic spraying method, and then drying to obtain a slurry preset layer on the surface of the Nb521 alloy; the drying temperature is 40 ℃, and the drying time is 90 min;
step four, uniformly mixing the raw material powder for preparing the Si-Mo-Zr sintered silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of the Nb521 alloy obtained in the step three, drying for 0.5h at 200 ℃, obtaining the silicide preset layer on the surface of the Nb521 alloy, then placing the silicide preset layer in a vacuum sintering furnace, and controlling the vacuum degree to be 7.0 multiplied by 10-3Carrying out high-temperature sintering under the Pa condition, and cooling along with the furnace to obtain a Si-Mo-Zr high-temperature protective coating with the thickness of 125 mu m and an in-situ reaction self-generated high-temperature diffusion barrier with the thickness of 6 mu m between the Nb521 alloy and the Si-Mo-Zr high-temperature protective coating; the specific process of the high-temperature sintering is as follows: the temperature is raised to 900 ℃ at the speed of 30 ℃/min and is preserved for 30min, and then the temperature is raised to 1450 ℃ at the speed of 10 ℃/min and is preserved for 60 min.
Through detection, compared with a Si-Mo-Zr high-temperature protective coating which is not applied with a high-temperature diffusion barrier with SiC as a main phase, the in-situ reaction self-generated high-temperature diffusion barrier of the embodiment can obviously slow down the interface diffusion reaction between the Nb521 alloy and the Si-Mo-Zr high-temperature protective coating on the outer layer at the temperature of below 1600 ℃, and the constant-temperature oxidation resistance service life of the Si-Mo-Zr high-temperature protective coating at the temperature of 1600 ℃ is obviously prolonged.
Example 3
The in-situ reaction self-generated high-temperature diffusion barrier on the surface of the Mo1 is positioned between the Mo1 and the Si-Cr-Ti high-temperature protection coating coated on the surface of the Mo1, SiC generated by a high-temperature chemical reaction between Si and graphene oxide is used as a main phase, and the thickness of the in-situ reaction self-generated high-temperature diffusion barrier is 0.5 μm.
The preparation method of the in-situ reaction self-generated high-temperature diffusion barrier on the surface of the Mo1 comprises the following steps:
step one, adopting 600#The surface of Mo1 is polished by SiC sand paper, then sand blasting and acid washing are carried out, and then the surface is immersed in acetone for degreasing treatment, so that pretreated Mo1 is obtained; the sand adopted by sand blasting is glass beads, the sand blasting pressure is 0.2MPa, and the sand blasting time is 8 min; the acid solution used for pickling is formed by mixing a hydrofluoric acid solution and a concentrated nitric acid solution according to a volume ratio of 7:4, the mass concentration of the hydrofluoric acid solution is 50%, the mass concentration of the concentrated nitric acid solution is 67%, and the pickling time is 1 min;
step two, mixing graphene oxide, Si powder and absolute ethyl alcohol, then placing the mixture in a ball mill, and carrying out ball milling and uniformly mixing for 180min under the condition that the rotating speed is 350 revolutions per minute to obtain graphene oxide slurry containing Si powder; the volume of the absolute ethyl alcohol is 20 times of the mass of the graphene oxide, wherein the unit of the volume is mL, and the unit of the mass is g; the grain size of the Si powder is not more than 1 mu m, and the atomic percentage of the graphene oxide and the Si in the graphene oxide slurry containing the Si powder is 1: 1;
thirdly, presetting the graphene oxide slurry containing Si powder obtained in the second step on the surface of the Mo1 pretreated in the first step by adopting a pneumatic spraying method, then drying, and obtaining a slurry preset layer on the surface of the Mo 1; the drying temperature is 60 ℃ and the drying time is 30 min;
step four, uniformly mixing the raw material powder for preparing the Si-Cr-Ti fused silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of Mo1 obtained in the step three, drying for 4h at 120 ℃, obtaining the silicide preset layer on the surface of Mo1, then placing the silicide preset layer in a vacuum sintering furnace, and controlling the vacuum degree to be 1.0 multiplied by 10-2Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a Si-Cr-Ti high-temperature protective coating with the thickness of 110 mu m and an in-situ reaction self-generated high-temperature diffusion barrier with the thickness of 0.5 mu m between the Mo1 and the Si-Cr-Ti high-temperature protective coating on the surface of the Mo 1; the specific process of the high-temperature sintering is as follows: the temperature is raised to 800 ℃ at the speed of 20 ℃/min and is preserved for 90min, and then the temperature is raised to 1450 ℃ at the speed of 12 ℃/min and is preserved for 30 min.
The in-situ reaction self-generated high-temperature diffusion barrier of the embodiment is detected to be capable of remarkably slowing down the interface diffusion reaction between Mo1 and the outer Si-Cr-Ti high-temperature protective coating at the temperature below 1400 ℃ relative to the Si-Cr-Ti coating without applying the high-temperature diffusion barrier with SiC as the main phase.
The refractory metal in this embodiment may also be a Mo alloy.
Example 4
The in-situ reaction self-generated high-temperature diffusion barrier on the surface of the refractory metal is positioned between W and the Si-Mo-Zr high-temperature protection coating coated on the surface of W, SiC generated by high-temperature chemical reaction between Si and graphene is used as a main phase, and the thickness of the in-situ reaction self-generated high-temperature diffusion barrier is 3 microns.
The preparation method of the refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier of the embodiment comprises the following steps:
step one, adopting 600#Polishing the surface of the W by using SiC sand paper, then performing sand blasting and acid washing, and then soaking the W into acetone for degreasing treatment to obtain pretreated W; the sand adopted by the sand blasting is corundum sand, the pressure of the sand blasting is 0.4MPa, and the sand blasting time is 4 min; the acid solution used for pickling is formed by mixing a hydrofluoric acid solution and a concentrated nitric acid solution according to the volume ratio of 6:3, the mass concentration of the hydrofluoric acid solution is 48%, the mass concentration of the concentrated nitric acid solution is 65%, and the pickling time is 3 min;
step two, mixing the graphene, the Si powder and the dispersing agent, placing the mixture in a ball mill, and carrying out ball milling and uniformly mixing for 120min under the condition that the rotating speed is 350 revolutions per minute to obtain graphene slurry containing the Si powder; the dispersing agent is formed by mixing varnish and ethyl acetate according to the volume ratio of 2:3, the volume of the dispersing agent is 25 times of the mass of graphene, wherein the unit of the volume is mL, and the unit of the mass is g; the grain size of the Si powder is not more than 1 mu m, and the atomic percentage of graphene and Si in the graphene slurry containing the Si powder is 1: 1;
step three, presetting the graphene slurry obtained in the step two on the surface of the W pretreated in the step one by adopting a pneumatic spraying method, and then drying to obtain a slurry preset layer on the surface of the W; the drying temperature is 70 ℃, and the drying time is 100 min;
step four, uniformly mixing the raw material powder for preparing the Si-Mo-Zr sintered silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of the W obtained in the step three, drying for 2 hours at 180 ℃, and obtaining silicon on the surface of the WPre-placing the layer, placing in a vacuum sintering furnace at vacuum degree of 8.0 × 10-3Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a Si-Mo-Zr high-temperature protective coating with the thickness of 140 mu m and an in-situ reaction self-generated high-temperature diffusion barrier with the thickness of 3 mu m between the W and the Si-Mo-Zr high-temperature protective coating; the specific process of the high-temperature sintering is as follows: the temperature is raised to 850 ℃ at the speed of 25 ℃/min and is preserved for 60min, and then the temperature is raised to 1500 ℃ at the speed of 15 ℃/min and is preserved for 80 min.
The in-situ reaction self-generated high-temperature diffusion barrier of the embodiment can obviously slow down the interface diffusion reaction between W and the outer Si-Mo-Zr high-temperature protective coating at the temperature of below 1500 ℃ relative to the Si-Mo-Zr coating without applying the high-temperature diffusion barrier with SiC as the main phase.
Example 5
The in-situ reaction self-generating high-temperature diffusion barrier on the surface of the refractory metal is positioned between Ta10W and the Si-Cr-Ti-Zr high-temperature protective coating coated on the surface of Ta10W, SiC generated by high-temperature chemical reaction between Si and graphene is used as a main phase, and the thickness of the in-situ reaction self-generating high-temperature diffusion barrier is 5 microns.
The preparation method of the refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier of the embodiment comprises the following steps:
step one, adopting 600#The surface of Ta10W is polished by SiC sand paper, then sand blasting and acid washing are carried out, and then the surface is immersed in acetone for degreasing treatment, so that pretreated Ta10W is obtained; the sand adopted by the sand blasting is corundum sand, the pressure of the sand blasting is 0.6MPa, and the time of the sand blasting is 3 min; the acid solution used for pickling is formed by mixing a hydrofluoric acid solution and a concentrated nitric acid solution according to the volume ratio of 6:3, the mass concentration of the hydrofluoric acid solution is 48%, the mass concentration of the concentrated nitric acid solution is 65%, and the pickling time is 3 min;
step two, mixing the graphene, the Si powder and the dispersing agent, placing the mixture in a ball mill, and carrying out ball milling and uniformly mixing for 120min under the condition that the rotating speed is 350 revolutions per minute to obtain graphene slurry containing the Si powder; the dispersing agent is formed by mixing varnish and ethyl acetate according to the volume ratio of 1:3.5, the volume of the dispersing agent is 25 times of the mass of graphene, wherein the unit of the volume is mL, and the unit of the mass is g; the grain size of the Si powder is not more than 1 mu m, and the atomic percentage of graphene and Si in the graphene slurry containing the Si powder is 1: 0.4;
step three, presetting the graphene slurry obtained in the step two on the surface of the pretreated Ta10W in the step one by adopting a pneumatic spraying method, then drying, and obtaining a slurry preset layer on the surface of Ta 10W; the drying temperature is 70 ℃, and the drying time is 100 min;
step four, uniformly mixing the raw material powder for preparing the Si-Cr-Ti-Zr sintered silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of Ta10W obtained in the step three, drying for 2h at 180 ℃, obtaining the silicide preset layer on the surface of Ta10W, then placing the silicide preset layer in a vacuum sintering furnace, and controlling the vacuum degree to be 1.0 multiplied by 10-2Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a Si-Cr-Ti-Zr high-temperature protective coating with the thickness of 150 mu m and an in-situ reaction self-generated high-temperature diffusion barrier with the thickness of 5 mu m between Ta10W and the Si-Cr-Ti-Zr high-temperature protective coating on the surface of Ta 10W; the specific process of the high-temperature sintering is as follows: the temperature is raised to 800 ℃ at the speed of 20 ℃/min and is preserved for 60min, and then the temperature is raised to 1500 ℃ at the speed of 15 ℃/min and is preserved for 90 min.
The in-situ reaction self-generated high-temperature diffusion barrier of the embodiment can obviously slow down the interface diffusion reaction between Ta10W and the Si-Cr-Ti-Zr high-temperature protective coating of the outer layer at the temperature below 1600 ℃ compared with the Si-Cr-Ti-Zr coating without applying the high-temperature diffusion barrier with SiC as the main phase.
Example 6
The in-situ reaction self-generated high-temperature diffusion barrier on the surface of the C103 niobium alloy is located between the C103 niobium alloy and the Si-Cr-Ti high-temperature protective coating coated on the surface of the C103 niobium alloy, SiC generated by a high-temperature chemical reaction between Si and graphene oxide is used as a main phase, and the thickness of the in-situ reaction self-generated high-temperature diffusion barrier is 4 μm.
The preparation method of the in-situ reaction self-generated high-temperature diffusion barrier on the surface of the C103 niobium alloy in the embodiment comprises the following steps:
step one, adopting 600#Polishing the surface of the C103 niobium alloy by SiC abrasive paper, then performing sand blasting and acid washing, and then immersing the C103 niobium alloy into acetone for degreasing to obtain a pretreated C103 niobium alloy; the sand adopted by the sand blasting is corundum sand, the pressure of the sand blasting is 0.4MPa, and the time of the sand blasting is 2 min; the acid solution used for pickling is formed by mixing a hydrofluoric acid solution and a concentrated nitric acid solution according to a volume ratio of 7:4, the mass concentration of the hydrofluoric acid solution is 50%, the mass concentration of the concentrated nitric acid solution is 67%, and the pickling time is 1 min;
step two, mixing graphene oxide, Si powder and absolute ethyl alcohol, then placing the mixture in a ball mill, and carrying out ball milling and uniformly mixing for 180min under the condition that the rotating speed is 350 revolutions per minute to obtain graphene oxide slurry containing Si powder; the volume of the absolute ethyl alcohol is 20 times of the mass of the graphene oxide, wherein the unit of the volume is mL, and the unit of the mass is g; the grain size of the Si powder is not more than 1 mu m, and the atomic percentage of the graphene oxide and the Si in the graphene oxide slurry containing the Si powder is 1: 0.6;
thirdly, presetting the graphene oxide slurry containing Si powder obtained in the second step on the surface of the C103 niobium alloy pretreated in the first step by adopting a pneumatic spraying method, and then drying to obtain a slurry preset layer on the surface of the C103 niobium alloy; the drying temperature is 60 ℃ and the drying time is 30 min;
step four, uniformly mixing the raw material powder for preparing the Si-Cr-Ti fused silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of the C103 niobium alloy obtained in the step three, drying for 4 hours at 120 ℃, obtaining a silicide preset layer on the surface of the C103 niobium alloy, then placing the silicide preset layer in a vacuum sintering furnace, and controlling the vacuum degree to be 9.0 multiplied by 10-3Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a Si-Cr-Ti high-temperature protective coating with the thickness of 110 mu m on the surface of the C103 niobium alloy and a Si-Cr-Ti high-temperature protective coating positioned on the C103 niobium alloyThe in-situ reaction self-generated high-temperature diffusion barrier with the thickness of 3 mu m between the two layers; the specific process of the high-temperature sintering is as follows: the temperature is raised to 800 ℃ at the speed of 20 ℃/min and is preserved for 90min, and then the temperature is raised to 1450 ℃ at the speed of 12 ℃/min and is preserved for 60 min.
Through detection, compared with a Si-Cr-Ti coating which is not applied with a high-temperature diffusion barrier with SiC as a main phase, the in-situ reaction self-generated high-temperature diffusion barrier of the embodiment can obviously slow down the interface diffusion reaction between the C103 niobium alloy and the Si-Cr-Ti high-temperature protective coating of the outer layer below 1400 ℃.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modification, change and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.
Claims (7)
1. The in-situ reaction self-generated high-temperature diffusion barrier on the surface of the refractory metal is characterized in that the in-situ reaction self-generated high-temperature diffusion barrier is positioned between the refractory metal and a high-temperature protective coating coated on the surface of the refractory metal, SiC generated by high-temperature chemical reaction between graphene or graphene oxide and Si is used as a main phase, and the thickness of the in-situ reaction self-generated high-temperature diffusion barrier is 0.5-10 mu m; the high-temperature protective coating is a fused silicide coating, and the high-temperature diffusion barrier can inhibit or slow down interfacial mutual diffusion reaction between the refractory metal and the high-temperature protective coating at the temperature below 2000 ℃.
2. The refractory metal surface in-situ reactive self-generating high temperature diffusion barrier of claim 1, wherein said refractory metal is Nb alloy, Mo alloy, W, W alloy, or Ta alloy.
3. A method of preparing a refractory metal surface in-situ reactive self-generating high temperature diffusion barrier as defined in claim 1 or 2, comprising the steps of:
step one, sequentially polishing, sand blasting, acid washing and degreasing the surface of the refractory metal to obtain the pretreated refractory metal;
step two, mixing graphene or graphene oxide with a dispersing agent, and then placing the mixture in a ball mill for ball milling and uniformly mixing to obtain graphene slurry or graphene oxide slurry; the volume of the dispersing agent is 10-30 times of the mass of graphene or graphene oxide, wherein the unit of the volume is mL, and the unit of the mass is g;
thirdly, presetting the graphene slurry or the graphene oxide slurry obtained in the second step on the surface of the refractory metal pretreated in the first step by adopting a pneumatic spraying method, then drying, and obtaining a slurry preset layer on the surface of the refractory metal; the drying temperature is 40-80 ℃ and the drying time is 30-120 min;
step four, uniformly mixing the raw material powder for preparing the fused silicide coating with a dispersing agent to obtain silicide composite suspension slurry; the dispersing agent is ethyl acetate solution of varnish;
step five, presetting the silicide composite suspension slurry obtained in the step four on the surface of the slurry preset layer of the refractory metal obtained in the step three, drying the slurry to obtain a silicide preset layer on the surface of the refractory metal, then placing the silicide preset layer in a vacuum sintering furnace, and keeping the vacuum degree of 7 multiplied by 10-3Pa～2.0×10-2Carrying out high-temperature sintering under the condition of Pa, and cooling along with the furnace to obtain a high-temperature protective coating on the surface of the refractory metal and an in-situ reaction self-generated high-temperature diffusion barrier between the refractory metal and the high-temperature protective coating; the specific process of the high-temperature sintering is as follows: firstly heating to 700-900 ℃ at the speed of 10-30 ℃/min, preserving the heat for 30-120 min, then heating to 1450-1550 ℃ at the speed of 10-15 ℃/min, preserving the heat for 30-90 min.
4. The method according to claim 3, wherein the sand used in the sand blasting in the step one is corundum sand, glass beads or zirconia sand, the pressure of the sand blasting is 0.2MPa to 0.8MPa, and the sand blasting time is 2min to 8 min; the acid solution used for pickling is formed by mixing hydrofluoric acid solution and concentrated nitric acid solution according to the volume ratio of (6-7) to (3-4), the mass concentration of the hydrofluoric acid solution is 40% -60%, the mass concentration of the concentrated nitric acid solution is 65% -68%, and the pickling time is 1-5 min.
5. The method as claimed in claim 3, wherein the dispersant mixed with the graphene oxide in the second step is distilled water or absolute ethyl alcohol, and the dispersant mixed with the graphene is formed by mixing varnish and ethyl acetate according to a volume ratio of (1-2) to (3-4).
6. The method according to claim 3, wherein the graphene slurry or graphene oxide slurry in the second step contains Si powder, the particle size of the Si powder is not more than 1 μm, and the atomic percentage of graphene in the graphene slurry or graphene oxide in the graphene oxide slurry to Si is 1: (0 to 1).
7. The method according to claim 3, wherein the drying temperature of the silicide slurry preset layer obtained in the fifth step is 40-200 ℃, and the drying time is 0.5-8 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910790625.5A CN110373628B (en) | 2019-08-26 | 2019-08-26 | Refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910790625.5A CN110373628B (en) | 2019-08-26 | 2019-08-26 | Refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110373628A CN110373628A (en) | 2019-10-25 |
| CN110373628B true CN110373628B (en) | 2020-06-12 |
Family
ID=68260713
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910790625.5A Active CN110373628B (en) | 2019-08-26 | 2019-08-26 | Refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110373628B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111334759B (en) * | 2020-03-05 | 2023-01-17 | 广东省科学院新材料研究所 | Application of diffusion barrier material, high-temperature coating, preparation method and application of high-temperature coating, and hot-end part of gas turbine |
| CN114606493B (en) * | 2021-11-19 | 2023-05-30 | 中南大学 | NbB-containing alloy for niobium alloy 2 /Nb 3 B 2 Antioxidant coating of composite diffusion barrier and preparation method thereof |
| CN115821262A (en) * | 2022-12-06 | 2023-03-21 | 西北有色金属研究院 | High-temperature diffusion barrier for carbide on surface of refractory metal and preparation method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08253876A (en) * | 1995-03-16 | 1996-10-01 | Kawasaki Steel Corp | High adhesion oxidation resistant coating film for c/c composite material and its formation |
| CN102061468B (en) * | 2011-01-24 | 2012-05-09 | 宁夏东方钽业股份有限公司 | High-temperature oxidation-resistant material and method for preparing high-temperature oxidation-resistant coating from same |
| CN105386041B (en) * | 2015-12-10 | 2017-12-15 | 西北有色金属研究院 | A kind of method that laser melting coating prepares modified compound Hf Ta metal coatings |
| CN106756999B (en) * | 2016-12-09 | 2018-10-23 | 西北有色金属研究院 | A kind of method that laser remolten improves refractory metal surfaces silicide coating surface quality |
| CN108048778B (en) * | 2017-12-14 | 2020-02-14 | 西北有色金属研究院 | Layered composite silicide/glass ceramic high-temperature oxidation-resistant coating and preparation method thereof |
| CN108004539B (en) * | 2017-12-14 | 2020-05-01 | 西北有色金属研究院 | Zr modified silicide coating on refractory metal surface and preparation method thereof |
-
2019
- 2019-08-26 CN CN201910790625.5A patent/CN110373628B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110373628A (en) | 2019-10-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110373628B (en) | Refractory metal surface in-situ reaction self-generated high-temperature diffusion barrier and preparation method thereof | |
| CN108585897B (en) | Refractory metal high-temperature oxidation-resistant Si-Mo-YSZ coating and preparation method thereof | |
| US20220097133A1 (en) | High entropy alloy powder for laser cladding and application method thereof | |
| CN108048778B (en) | Layered composite silicide/glass ceramic high-temperature oxidation-resistant coating and preparation method thereof | |
| KR101393327B1 (en) | Plasma spray surface coating on Zirconium alloy for increasing the corrosion resistance at very high temperature | |
| CN110330357B (en) | Connecting material for connecting silicon carbide materials and application thereof | |
| Zhang et al. | Joining of Cf/SiC ceramic matrix composites: a review | |
| CN114525424B (en) | Titanium-based composite material and preparation method thereof | |
| Yuan et al. | Processing map and hot deformation behavior of Ta-particle reinforced TiAl composite | |
| CN109434119B (en) | Preparation method of high-toughness MXene phase doped molybdenum alloy | |
| CN104711457B (en) | High temperature solder and application thereof | |
| CN108004539B (en) | Zr modified silicide coating on refractory metal surface and preparation method thereof | |
| CN112063966B (en) | Method for improving high-temperature ablation resistance of molybdenum alloy surface | |
| CN105506427B (en) | Modified compound Hf Ta coatings in a kind of tantalum alloy surface and preparation method thereof | |
| CN113088883A (en) | High-temperature alloy composite metal ceramic coating and preparation method thereof | |
| CN114107888B (en) | Novel tantalum-based Si-Mo-ZrB containing TaB diffusion barrier layer 2 Composite coating and three-step preparation method thereof | |
| CN114351007B (en) | High-temperature-resistant fastener and manufacturing method thereof | |
| CN115821262A (en) | High-temperature diffusion barrier for carbide on surface of refractory metal and preparation method thereof | |
| CN117721409A (en) | Preparation method of high-temperature wear-resistant silicide protection layer on surface of refractory high-entropy alloy | |
| Liu et al. | Ablation resistance and mechanism of SiC/ZrC-ZrB2 double layer coating for C/C composites under plasma flame | |
| CN104195402A (en) | Preparing method of high-temperature antioxidant fastener and antioxidant material | |
| CN109913787B (en) | Preparation method of metallurgically bonded wear-resistant corrosion-resistant composite coating | |
| CN106868354A (en) | A kind of Anti-corrosion composite metal material and preparation method thereof | |
| CN115821258B (en) | Heat-resistant scouring and thermal shock resistant silicide coating and preparation method thereof | |
| CN115849933B (en) | Silicon carbide ceramic connecting piece and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |