CN115522157A - Preparation method of LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying - Google Patents
Preparation method of LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying Download PDFInfo
- Publication number
- CN115522157A CN115522157A CN202211331381.2A CN202211331381A CN115522157A CN 115522157 A CN115522157 A CN 115522157A CN 202211331381 A CN202211331381 A CN 202211331381A CN 115522157 A CN115522157 A CN 115522157A
- Authority
- CN
- China
- Prior art keywords
- lsmo
- temperature
- wave
- powder
- absorbing coating
- 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.)
- Granted
Links
- 229910002075 lanthanum strontium manganite Inorganic materials 0.000 title claims abstract description 134
- 238000000576 coating method Methods 0.000 title claims abstract description 107
- 239000011248 coating agent Substances 0.000 title claims abstract description 97
- 238000007751 thermal spraying Methods 0.000 title claims abstract description 24
- 238000002360 preparation method Methods 0.000 title claims abstract description 19
- 239000000843 powder Substances 0.000 claims abstract description 58
- 238000000034 method Methods 0.000 claims abstract description 27
- 239000006096 absorbing agent Substances 0.000 claims abstract description 25
- 239000002131 composite material Substances 0.000 claims abstract description 24
- 238000007750 plasma spraying Methods 0.000 claims abstract description 21
- 238000005054 agglomeration Methods 0.000 claims abstract description 9
- 230000002776 aggregation Effects 0.000 claims abstract description 9
- 238000005469 granulation Methods 0.000 claims abstract description 9
- 230000003179 granulation Effects 0.000 claims abstract description 9
- 238000003980 solgel method Methods 0.000 claims abstract description 8
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 24
- 238000001035 drying Methods 0.000 claims description 14
- 239000000243 solution Substances 0.000 claims description 11
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 239000012266 salt solution Substances 0.000 claims description 9
- 150000003839 salts Chemical class 0.000 claims description 8
- 238000003756 stirring Methods 0.000 claims description 7
- 238000000227 grinding Methods 0.000 claims description 6
- 239000004570 mortar (masonry) Substances 0.000 claims description 6
- DHEQXMRUPNDRPG-UHFFFAOYSA-N strontium nitrate Chemical compound [Sr+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O DHEQXMRUPNDRPG-UHFFFAOYSA-N 0.000 claims description 6
- 238000000137 annealing Methods 0.000 claims description 5
- 239000000084 colloidal system Substances 0.000 claims description 5
- 238000007873 sieving Methods 0.000 claims description 5
- 238000005507 spraying Methods 0.000 claims description 5
- 229910002204 La0.8Sr0.2MnO3 Inorganic materials 0.000 claims description 3
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 3
- 239000000853 adhesive Substances 0.000 claims description 3
- 230000001070 adhesive effect Effects 0.000 claims description 3
- 239000008367 deionised water Substances 0.000 claims description 3
- 229910021641 deionized water Inorganic materials 0.000 claims description 3
- FYDKNKUEBJQCCN-UHFFFAOYSA-N lanthanum(3+);trinitrate Chemical compound [La+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O FYDKNKUEBJQCCN-UHFFFAOYSA-N 0.000 claims description 3
- MIVBAHRSNUNMPP-UHFFFAOYSA-N manganese(2+);dinitrate Chemical compound [Mn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MIVBAHRSNUNMPP-UHFFFAOYSA-N 0.000 claims description 3
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000005979 thermal decomposition reaction Methods 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims 1
- 239000000463 material Substances 0.000 abstract description 5
- 239000000758 substrate Substances 0.000 abstract description 4
- 239000011358 absorbing material Substances 0.000 description 16
- 230000008859 change Effects 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- 238000012876 topography Methods 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 6
- 238000002310 reflectometry Methods 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 239000006185 dispersion Substances 0.000 description 5
- 238000010521 absorption reaction Methods 0.000 description 4
- 230000002547 anomalous effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 description 4
- 239000011159 matrix material Substances 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 230000010287 polarization Effects 0.000 description 4
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000011247 coating layer Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000003760 magnetic stirring Methods 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 230000004580 weight loss Effects 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000001595 flow curve Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000003446 ligand Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
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
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
- C23C4/10—Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
-
- 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
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
- C23C4/134—Plasma spraying
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electromagnetism (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The invention discloses a preparation method of an LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying, which comprises the following steps: 1. preparing LSMO powder by a sol-gel method; 2. preparing an LSMO/AT13 composite wave absorbing agent by a mechanical agglomeration granulation method; 3. and preparing the LSMO/AT13 high-temperature wave-absorbing coating by a plasma spraying method. According to the invention, the LSMO/AT13 composite wave absorbing agent is prepared by sequentially adopting a sol-gel method and a mechanical agglomeration granulation method, and the LSMO/AT13 high-temperature wave absorbing coating is prepared by plasma spraying, so that the high-temperature wave absorbing coating has high density, good combination degree of the coating and a substrate, excellent high-temperature resistance and good high-temperature microwave wave absorbing performance, and the current situation that the material system is relatively single in the field of high-temperature wave absorbing coatings is made up.
Description
Technical Field
The invention belongs to the technical field of high-temperature electromagnetic wave absorption, and particularly relates to a preparation method of an LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying.
Background
With the rapid development of electronic information technology and radar detection technology, the wave-absorbing material still needs to meet the requirements of harsh environments such as high temperature in some special occasions, the high temperature environment brings great challenges to the wave-absorbing performance of the wave-absorbing material and the mechanical performance of a coating, and the common magnetic and carbon-based absorbent under the normal temperature condition is often not optimistic in the wave-absorbing performance under the high temperature environment due to low Curie temperature, poor oxidation resistance and the like, so that the research of a novel high temperature resistant wave-absorbing material capable of working under the high temperature harsh environment is necessary.
The wave-absorbing material is mainly divided into a structural wave-absorbing material and a coating wave-absorbing material, and compared with the structural wave-absorbing material, the coating wave-absorbing material has the defect of complex design and application, and has become an important way for the application of the wave-absorbing material by virtue of the advantages of no change of the appearance structure, convenience in application and maintenance and the like. The coating type wave-absorbing material technology is not only the research and development of high-performance wave-absorbing materials, but also the final target of the preparation of stealth coatings with excellent performance by applying the wave-absorbing materials, and is a key way for the wave-absorbing materials to be really applied. Therefore, the development of the coating preparation technology is an important circle for promoting the application of the wave-absorbing material. In recent years, due to the technical advantages of thermal spraying in the aspect of preparing functional coatings, researchers try to prepare the wave-absorbing coatings by the thermal spraying technology, the technical feasibility is verified, the problems of poor mechanical property, non-ideal wave-absorbing effect and the like of the wave-absorbing coatings are expected to be solved by the thermal spraying technology, and the application of the thermal spraying in the high-temperature wave-absorbing coatings is realized.
Disclosure of Invention
The invention aims to solve the technical problem of providing a preparation method of an LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying aiming AT the defects of the prior art. The method adopts a sol-gel method and a mechanical agglomeration granulation method to prepare the LSMO/AT13 composite wave absorbing agent, and prepares the LSMO/AT13 high-temperature wave absorbing coating through plasma spraying, and the high-temperature wave absorbing coating has high density, good combination degree of the coating and a matrix, excellent high-temperature resistance and good high-temperature microwave wave absorbing performance, and makes up the current situation that a material system is relatively single in the field of high-temperature wave absorbing coatings.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a preparation method of an LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized by comprising the following steps:
firstly, preparing LSMO powder by a sol-gel method; according to La 0.8 Sr 0.2 MnO 3 Adding lanthanum nitrate, strontium nitrate and manganese nitrate solution into deionized water, continuously performing magnetic stirring until the solution is clear to obtain mixed salt solution, then adding citric acid, continuously performing magnetic stirring at 80-90 ℃ to obtain orange gel, thermally decomposing the orange gel, grinding into powder, and annealing to obtain LSMO powder;
step two, preparing the LSMO/AT13 composite wave absorbing agent by a mechanical agglomeration granulation method: putting the LSMO powder and AT13 powder prepared in the first step into a mortar, adding a polyvinyl alcohol solution serving as an adhesive into the mortar, continuously stirring into a colloid, drying, grinding into powder and sieving to prepare the LSMO/AT13 composite wave absorbing agent;
step three, preparing the LSMO/AT13 high-temperature wave-absorbing coating by a plasma spraying method: and (3) carrying out plasma spraying by taking the LSMO/AT13 composite wave absorbing agent prepared in the step two as a raw material to prepare the LSMO/AT13 high-temperature wave absorbing coating.
The invention provides a doped perovskite type manganese oxide La-based catalyst 0.8 Sr 0.2 MnO 3 The high-temperature wave-absorbing coating (abbreviated as LSMO) is prepared by firstly preparing LSMO powder by adopting a sol-gel method, then preparing an LSMO/AT13 composite wave-absorbing agent by adopting a mechanical agglomeration granulation method, and then preparing the LSMO/AT13 high-temperature wave-absorbing coating by adopting a plasma spraying method, wherein the LSMO/AT13 high-temperature wave-absorbing coating has the advantages of high density, good combination degree of the coating and a matrix, excellent high-temperature resistance and good high-temperature microwave wave-absorbing performance.
The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized in that in the first step, the total concentration of metal salts in the mixed salt solution is 0.3-0.5 mol/L, and the molar ratio of citric acid to the metal salts in the mixed salt solution is 1. The invention avoids the over-high concentration of the metal salt by the total concentration of the metal saltThe dispersion is not uniform, and the addition amount of the citric acid is controlled to be fully chelated with the metal salt ligand, so that excessive citric acid is prevented from being thermally decomposed to generate carbon in the subsequent process, and further more impurity phase SrCO is generated 3 And the quality of the high-temperature wave-absorbing coating is ensured.
The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized in that the thermal decomposition temperature in the step one is 200 ℃, and the time is 2 hours; the temperature of the annealing treatment is 700-900 ℃, and the time is 12h.
The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized in that the mass of the LSMO powder in the second step is less than 30% of the total mass of the LSMO powder and the AT13 powder. By controlling the mass content of the LSMO powder, the wave absorbing performance of the high-temperature wave absorbing coating is prevented from being influenced by the reduction of the anti-matching performance of the high-temperature wave absorbing coating due to the excessive LSMO, and the effective wave absorbing effect is difficult to achieve due to the poor microwave loss capacity of the high-temperature wave absorbing coating due to the excessive LSMO.
The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized in that the drying in the step two is carried out in a constant-temperature drying box, the drying temperature is 130-150 ℃, the drying time is 10 hours, and the sieving is carried out by adopting a 160-mesh sieve. The full drying is ensured by controlling the drying equipment, the temperature and the time; the particle size of the LSMO/AT13 composite wave absorbing agent is controlled by controlling the particle size of the powder passing through a 160-mesh sieve to correspond to 98 mu m, so that the LSMO/AT13 composite wave absorbing agent is suitable for plasma spraying, the problem that the quality of a high-temperature wave absorbing coating is not completely influenced by powder melting due to overlarge particle size and the problem that the spray gun is blocked due to the fact that the powder is easily bridged AT the gun mouth of the plasma spray gun due to undersize particle size are avoided, and the smooth proceeding of the plasma spraying process is further ensured.
The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized in that the main gas adopted by the plasma spraying in the third step is N 2 5% by volume of Ar-N 2 Mixed gas, powder feeding gas is N 2 The main flow rate is 20L/min, the voltage is 30V, the current is 250A, the powder feeding speed is 2.5g/min, the powder feeding air flow rate is 5L/min, and the spraying distance is 100mm. The invention relates to a deviceBy using Ar-N 2 The mixed gas is used as main gas, the enthalpy value of plasma gas in the spraying process is adjusted, and other process parameters including powder feeding rate, voltage, current, spraying distance and the like are combined, so that the melting state of the LSMO/AT13 composite wave absorbing agent is better, and the quality of the high-temperature wave absorbing coating is improved.
The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized in that the mass content of the LSMO in the LSMO/AT13 high-temperature wave-absorbing coating in the third step is not more than 30%.
Compared with the prior art, the invention has the following advantages:
1. the invention sequentially adopts a sol-gel method to prepare LSMO powder, a mechanical agglomeration granulation method to prepare LSMO/AT13 composite wave absorbing agent, and then a plasma spraying method to prepare La based on doped perovskite type manganese oxide 0.8 Sr 0.2 MnO 3 The LSMO/AT13 high-temperature wave-absorbing coating has excellent high-temperature resistance and good high-temperature microwave wave-absorbing performance, and makes up the current situation that a material system is relatively single in the field of high-temperature wave-absorbing coatings.
2. The LSMO/AT13 high-temperature wave-absorbing coating prepared by the plasma spraying method has high density and good combination degree of the coating and a matrix, avoids the influence and the excessive change on the quality of the high-temperature wave-absorbing coating, and ensures the quality of the high-temperature wave-absorbing coating.
3. The LSMO/AT13 high-temperature wave-absorbing coating prepared by the invention has excellent high-temperature resistance, and can resist 1200 ℃ high temperature without oxidation reaction.
4. The LSMO/AT13 high-temperature wave-absorbing coating prepared by the invention has good and stable high-temperature wave-absorbing performance, when the thickness of the coating is 1.7mm, the effective bandwidth (< -10 dB) of 673K and 773K AT an X wave band can respectively reach 2.3GHz and 1.8GHz, when the thickness of the coating is 1.4mm, the effective bandwidth of 873K can reach 2.1GHz, and when the thickness of the coating is 1.3mm, the effective bandwidth of 873K and 973K can respectively reach 1.3GHz and 1.0GHz.
The technical solution of the present invention is further described in detail by the accompanying drawings and examples.
Drawings
Fig. 1 is a micro-topography of the LSMO powder prepared in example 1 of the present invention.
Fig. 2 is a micro-topography of the LSMO/AT13 composite wave absorber prepared in example 1 of the present invention.
FIG. 3 is a micro-topography of the LSMO/AT13 composite wave absorber after plasma spraying in example 1 of the present invention.
Fig. 4 is an end surface micro-topography of the LSMO/AT13 high-temperature wave-absorbing coating prepared in example 1 of the present invention.
FIG. 5 is an XRD pattern of the LSMO/AT13 high temperature wave-absorbing coating prepared in examples 1-3 and comparative example 1 of the present invention.
Fig. 6a is a TG diagram of the LSMO/AT13 high temperature microwave absorbing coating prepared in example 1 of the present invention.
FIG. 6b is a DSC of the LSMO/AT13 high temperature absorbing coating prepared in example 1 of the present invention.
FIG. 7a is a graph of the real part of complex permittivity ε' of the LSMO/AT13 high temperature wave-absorbing coating prepared in example 1 of the present invention changing with frequency.
FIG. 7b is a graph showing the change of the imaginary part ε' of the complex dielectric constant of the LSMO/AT13 high-temperature wave-absorbing coating prepared in example 1 of the present invention with frequency.
FIG. 8a is a reflectivity loss graph of the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.3mm prepared in example 1 of the present invention AT different temperatures.
Fig. 8b is a reflectivity loss graph of the LSMO/AT13 high temperature absorbing coating with a thickness of 1.4mm prepared in example 4 of the present invention AT different temperatures.
FIG. 8c is a graph of reflectivity loss of the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.7mm prepared in example 5 of the present invention AT different temperatures.
FIG. 8d is a reflectivity loss graph of the LSMO/AT13 high temperature wave-absorbing coating with the thickness of 1.9mm prepared in example 6 of the present invention AT different temperatures.
Detailed Description
Example 1
The embodiment comprises the following steps:
firstly, preparing LSMO powder by a sol-gel method; according to La 0.8 Sr 0.2 MnO 3 The stoichiometric ratio of (a) to (b),adding lanthanum nitrate, strontium nitrate and a manganese nitrate solution with the mass concentration of 50% into deionized water, continuously magnetically stirring until the solution is clear to obtain a mixed salt solution, then adding citric acid, continuously magnetically stirring at 80-90 ℃ to obtain orange gel, thermally decomposing the orange gel at 200 ℃ for 2 hours, grinding the orange gel into powder, and annealing at 700 ℃ for 12 hours to prepare LSMO powder; the total concentration of metal salts in the mixed salt solution is 0.5mol/L, and the molar ratio of the citric acid to the metal salts in the mixed salt solution is 1;
step two, preparing the LSMO/AT13 composite wave absorbing agent by a mechanical agglomeration granulation method: putting the LSMO powder and AT13 powder prepared in the first step into a mortar, adding a polyvinyl alcohol solution serving as an adhesive into the mortar, continuously stirring into a colloid, then putting the colloid into a constant-temperature drying box, continuously drying for 10 hours AT 150 ℃, grinding into powder, and sieving by a 160-mesh sieve to prepare the LSMO/AT13 composite wave absorbing agent; the mass of the LSMO powder is 20% of the total mass of the LSMO powder and the AT13 powder;
step three, preparing the LSMO/AT13 high-temperature wave-absorbing coating by a plasma spraying method: carrying out plasma spraying on an aluminum substrate by taking the LSMO/AT13 composite wave absorbing agent prepared in the step two as a raw material to prepare an LSMO/AT13 high-temperature wave absorbing coating with the thickness of 1.3 mm; the main gas adopted by the plasma spraying is N 2 Ar-N with volume content of 5% 2 Mixed gas, powder feeding gas is N 2 The main flow rate is 20L/min, the voltage is 30V, the current is 250A, the powder feeding speed is 2.5g/min, the powder feeding air flow rate is 5L/min, and the spraying distance is 100mm.
Fig. 1 is a micro-topography of the LSMO powder prepared in this example, and fig. 2 is a micro-topography of the LSMO/AT13 composite wave-absorbing agent prepared in this example, and it can be known from fig. 1 and fig. 2 that the particle size of the LSMO/AT13 composite wave-absorbing agent prepared in this example is 30 μm to 50 μm, the shape is relatively regular and the degree of spheroidization is high, and the surface of a single particle is coated with nano-sized LSMO, which illustrates that the LSMO wave-absorbing agent and the AT13 matrix are effectively agglomerated by using a mechanical agglomeration granulation method.
Fig. 3 is a micro-topography of the LSMO/AT13 composite wave-absorbing agent after plasma spraying in this embodiment, and as can be seen from fig. 3, the LSMO/AT13 composite wave-absorbing agent after plasma spraying has relatively uniform particle size and flat and dense particle surface, which illustrates that the melting condition of the LSMO/AT13 composite wave-absorbing agent is better.
Fig. 4 is a micro-topography diagram of an end face of the LSMO/AT13 high-temperature wave-absorbing coating prepared in this embodiment, and it can be seen from fig. 4 that the melting degree between the LSMO/AT13 high-temperature wave-absorbing coating and the aluminum substrate is good, that is, the bonding degree between the high-temperature wave-absorbing coating and the substrate is good, and no obvious layering phenomenon occurs in the high-temperature wave-absorbing coating.
Fig. 6a is a TG diagram of the LSMO/AT13 high-temperature microwave absorbing coating prepared in this embodiment, and as can be seen from fig. 6a, in a range from room temperature to 1200 ℃, the high-temperature microwave absorbing coating does not have a severe weight loss phenomenon, and the weight loss of a sample in the whole temperature rise process is less than 0.5%, which indicates that the LSMO/AT13 high-temperature microwave absorbing coating prepared by the present invention has excellent high temperature resistance.
Fig. 6b is a DSC diagram of the LSMO/AT13 high-temperature wave-absorbing coating prepared in this embodiment, and it can be seen from fig. 6b that the heat flow curve of the high-temperature wave-absorbing coating is close to 0, and no violent chemical reaction occurs in a high-temperature aerobic environment, which indicates that the LSMO/AT13 high-temperature wave-absorbing coating prepared in the present invention has good oxidation resistance.
FIG. 7a is a graph showing the real part ε 'of the complex dielectric constant of the LSMO/AT13 high temperature wave-absorbing coating prepared in this example as a function of frequency, FIG. 7b is a graph showing the imaginary part ε' of the complex dielectric constant of the LSMO/AT13 high temperature wave-absorbing coating prepared in this example as a function of frequency, and it can be seen from FIGS. 7a and 7b that ε 'shows a gradually increasing trend with increasing temperature, and the change rule of ε' with temperature is relatively unobvious and does not change substantially below 573K, and when the temperature is between 573K and 873K, ε 'is lower AT low frequency with increasing temperature, the phenomenon is higher AT high frequency, meanwhile, the attenuation of epsilon' is synchronous with the increase of epsilon ', epsilon' is in a descending state when epsilon 'reaches a peak value near 11GHz, the phenomenon of medium anomalous dispersion occurs, so that polarization can be completely established AT low frequency, the polarization loss capability is poor, epsilon' is small, polarization cannot be established in time AT high frequency, the polarization loss capability is stronger along with the increase of frequency, epsilon 'has a remarkable increasing trend, and epsilon' leaves an anomalous dispersion region and has a remarkable increasing trend when the temperature is higher than 873K. In conclusion, the complex dielectric constant of the LSMO/AT13 high-temperature wave-absorbing coating prepared by the invention is relatively stable along with the change of temperature, and the sharp rise of the complex dielectric constant is mainly positioned after the occurrence of medium anomalous dispersion, so that when the high-temperature wave-absorbing coating is prepared by utilizing a thermal spraying process, the area of the material with the anomalous dispersion needs to be considered so as to reasonably optimize the wave-absorbing material.
Example 2
The present embodiment differs from embodiment 1 in that: and the mass of the LSMO powder in the second step is 10% of the total mass of the LSMO powder and the AT13 powder.
Example 3
The present embodiment differs from embodiment 1 in that: and the mass of the LSMO powder in the second step is 30% of the total mass of the LSMO powder and the AT13 powder.
Comparative example 1
The comparative example differs from example 1 in that: and the mass of the LSMO powder in the second step is 0% of the total mass of the LSMO powder and the AT13 powder.
FIG. 5 is XRD patterns of LSMO/AT13 high temperature wave-absorbing coatings prepared in examples 1-3 and comparative example 1 of the present invention, and it can be seen from FIG. 5 that compared with the unstable phase γ -Al in the high temperature wave-absorbing coating prepared by not introducing LSMO powder in comparative example 1 2 O 3 The diffraction peak intensity of the invention is larger, and the stable alpha-Al in the high-temperature wave-absorbing coating prepared by introducing LSMO/AT13 in the embodiments 1-3 of the invention 2 O 3 Compared with gamma-Al 2 O 3 The diffraction peak intensity is obviously enhanced, and TiO appears 2 The standard diffraction peak of (A) shows that the addition of LSMO helps to inhibit chilling phenomenon and TiO during plasma spraying 2 The deoxidation phenomenon of (a); meanwhile, with the increase of the mass content of the LSMO powder, the diffraction peak intensities of the high-temperature wave-absorbing coating layer AT the positions near 36 degrees and 45.4 degrees are obviously enhanced, and the unique double-peak phenomenon of the XRD pattern of the LSMO is kept, so that the LSMO is proved to have small crystal structure change in the plasma thermal spraying process and have no serious chemical reaction in high-temperature plasma flame flow, and further the LSMO is proved to be a material suitable for a thermal spraying process, and the LSMO/AT13 high-temperature wave-absorbing coating layer is prepared by thermal sprayingWave coatings are possible.
Example 4
The present embodiment differs from embodiment 1 in that: and the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.4mm is prepared in the third step.
Example 5
The present embodiment differs from embodiment 1 in that: and the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.7mm is prepared in the third step.
Example 6
The present embodiment differs from embodiment 1 in that: and the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.9mm is prepared in the third step.
Fig. 8a to 8d are reflectivity loss graphs of the LSMO/AT13 high-temperature wave-absorbing coating with thickness of 1.3mm, thickness of 1.4mm, thickness of 1.7mm, and thickness of 1.9mm prepared in examples 1 and 4 to 6 respectively, AT different temperatures, as can be seen from fig. 8a to 8d, the LSMO/AT13 high-temperature wave-absorbing coating with thickness of 1.7mm and thickness of 1.9mm has good microwave absorption performance AT a temperature below 873K, wherein when the thickness is 1.7mm, the effective bandwidths AT 673K and 773K can respectively reach 2.3GHz and 1.8GHz, and AT 973K, the effective bandwidth also exists AT low frequency, and the reflectivity loss curve tends to move to low frequency with the increase of temperature; when the temperature rises to more than 873K, the complex dielectric constant is remarkably increased, so that the optimal impedance matching performance is realized AT a lower thickness, the effective bandwidth of the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.4mm AT 873K can reach 2.1GHz, and the effective bandwidths of the LSMO/AT13 high-temperature wave-absorbing coating with the thickness of 1.3mm AT 873K and 973K are 1.3GHz and 1.0GHz respectively. In conclusion, the LSMO/AT13 high-temperature wave-absorbing coating prepared by the invention still has good microwave absorption performance AT high temperature, the excellent oxidation resistance shows that the LSMO/AT13 high-temperature wave-absorbing coating has the capability of being applied to microwave absorption AT higher temperature, and the stable chemical property of the LSMO/AT13 high-temperature wave-absorbing coating in a high-temperature environment can ensure that the performance of the LSMO/AT13 high-temperature wave-absorbing coating is basically not changed after repeated temperature rise, so that the LSMO/AT13 high-temperature wave-absorbing coating is suitable for high-temperature wave-absorbing materials.
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. A preparation method of an LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying is characterized by comprising the following steps:
firstly, preparing LSMO powder by a sol-gel method; according to La 0.8 Sr 0.2 MnO 3 Adding lanthanum nitrate, strontium nitrate and manganese nitrate solution into deionized water, continuously magnetically stirring until the solution is clear to obtain mixed salt solution, then adding citric acid, continuously magnetically stirring at 80-90 ℃ to obtain orange gel, thermally decomposing the orange gel, grinding into powder, and annealing to obtain LSMO powder;
step two, preparing the LSMO/AT13 composite wave absorbing agent by a mechanical agglomeration granulation method: putting the LSMO powder and AT13 powder prepared in the first step into a mortar, adding a polyvinyl alcohol solution serving as an adhesive into the mortar, continuously stirring the mixture into a colloid, drying, grinding the colloid into powder and sieving the powder to prepare the LSMO/AT13 composite wave absorbing agent;
step three, preparing the LSMO/AT13 high-temperature wave-absorbing coating by a plasma spraying method: and (3) carrying out plasma spraying by taking the LSMO/AT13 composite wave absorbing agent prepared in the step two as a raw material to prepare the LSMO/AT13 high-temperature wave absorbing coating.
2. The preparation method of the thermally sprayed LSMO/AT13 high-temperature wave-absorbing coating according to claim 1, wherein in the first step, the total concentration of the metal salt in the mixed salt solution is 0.3mol/L to 0.5mol/L, and the molar ratio of the citric acid to the metal salt in the mixed salt solution is 1.
3. The preparation method of the thermally sprayed-based LSMO/AT13 high-temperature wave-absorbing coating according to claim 1, wherein the thermal decomposition temperature in the first step is 200 ℃ and the time is 2h; the temperature of the annealing treatment is 700-900 ℃, and the time is 12h.
4. The method for preparing the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying according to claim 1, wherein the mass of the LSMO powder in the second step is less than 30% of the total mass of the LSMO powder and the AT13 powder.
5. The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying according to claim 1, wherein in the second step, the drying is carried out in a constant-temperature drying oven, the drying temperature is 130 ℃ -150 ℃, the drying time is 10h, and the sieving is carried out by adopting a 160-mesh sieve.
6. The method for preparing the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying according to claim 1, wherein the main gas adopted by the plasma spraying in the third step is N 2 Ar-N with volume content of 5% 2 Mixed gas, powder feeding gas is N 2 The main gas flow is 20L/min, the voltage is 30V, the current is 250A, the powder feeding speed is 2.5g/min, the powder feeding gas flow is 5L/min, and the spraying distance is 100mm.
7. The preparation method of the LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying according to claim 1, wherein the LSMO mass content in the LSMO/AT13 high-temperature wave-absorbing coating in the third step is not more than 30%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211331381.2A CN115522157B (en) | 2022-10-28 | 2022-10-28 | Preparation method of LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211331381.2A CN115522157B (en) | 2022-10-28 | 2022-10-28 | Preparation method of LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115522157A true CN115522157A (en) | 2022-12-27 |
| CN115522157B CN115522157B (en) | 2024-02-23 |
Family
ID=84703895
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211331381.2A Active CN115522157B (en) | 2022-10-28 | 2022-10-28 | Preparation method of LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115522157B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101880162A (en) * | 2010-04-08 | 2010-11-10 | 山东大学 | Rare earth perovskite type direct contact temperature-measuring thin film and element thereof |
| WO2014089689A1 (en) * | 2012-12-13 | 2014-06-19 | Canadian Space Agency | Spacecraft smart thermal radiator based on thermochromic coatings deposited on aluminum panel |
| CN107759216A (en) * | 2017-11-03 | 2018-03-06 | 太原理工大学 | A kind of method that sol-gal process prepares strontium lanthanum manganese oxide/CaCu 3 Ti 4 O compound magnetoelectric ceramic material |
-
2022
- 2022-10-28 CN CN202211331381.2A patent/CN115522157B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101880162A (en) * | 2010-04-08 | 2010-11-10 | 山东大学 | Rare earth perovskite type direct contact temperature-measuring thin film and element thereof |
| WO2014089689A1 (en) * | 2012-12-13 | 2014-06-19 | Canadian Space Agency | Spacecraft smart thermal radiator based on thermochromic coatings deposited on aluminum panel |
| CN107759216A (en) * | 2017-11-03 | 2018-03-06 | 太原理工大学 | A kind of method that sol-gal process prepares strontium lanthanum manganese oxide/CaCu 3 Ti 4 O compound magnetoelectric ceramic material |
Non-Patent Citations (1)
| Title |
|---|
| C. O. EHI-EROMOSELEB. I. ITAE. E. J. IWEALA: "Enhanced microwave absorption of La0.7Sr0.3MnO3−δ based composites with added carbon black", CERAMICS INTERNATIONAL, 22 August 2013 (2013-08-22), pages 3947 - 3951 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115522157B (en) | 2024-02-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113088251B (en) | Bimetallic MOFs derived Fe 3 O 4 Preparation method of/Fe/C composite wave-absorbing material | |
| CN101650977B (en) | Nano iron oxide /graphite composite electromagnetic absorption material and preparation method thereof | |
| CN110002458A (en) | A kind of porous microsphere/ferrite/conductive layer composite material for microwave absorption | |
| CN113249092B (en) | Metal organic framework complex composite wave-absorbing powder and preparation method thereof | |
| CN113248725A (en) | Preparation method of electromagnetic wave absorbing material based on MOF derivation and electromagnetic wave absorbing material | |
| CN112341199A (en) | High-entropy wave-absorbing carbide ceramic powder material, preparation method and application thereof | |
| CN109095919B (en) | Barium titanate/cobaltosic oxide complex phase millimeter wave absorbing powder with multistage microstructure distribution and preparation method thereof | |
| CN110257958A (en) | A kind of vanadium nitride/carbon nano-fiber microwave absorption and preparation method thereof | |
| CN112408409A (en) | High-temperature-resistant high-entropy wave-absorbing ceramic and preparation method and application thereof | |
| CN101941731A (en) | Preparation method of void type nano-sheet zinc oxide and activated carbon load complex | |
| CN113697863A (en) | Ferroferric oxide/carbon nanosheet composite material with excellent electromagnetic wave absorption performance and preparation method and application thereof | |
| CN102153338A (en) | Seepage type barium titanate-nickel zinc ferrite composite ceramic wave absorption material and preparation method thereof | |
| CN114634208A (en) | Oxide composite material and preparation method and application thereof | |
| CN110028930B (en) | HalS-Fe3O4@ C composite material and preparation method and application thereof | |
| CN109293939B (en) | Preparation method of ZIF-67 with hierarchical pore structure and preparation method of honeycomb-like carbon/cobalt wave-absorbing material | |
| CN103390479A (en) | Inorganic composite micro powder with high electromagnetic shielding property and preparation method thereof | |
| CN115522157B (en) | Preparation method of LSMO/AT13 high-temperature wave-absorbing coating based on thermal spraying | |
| CN103864423B (en) | A kind of preparation method of microwave dielectric ceramic materials | |
| CN109179490B (en) | Lanthanum-doped tin dioxide hollow porous micro-nanospheres and preparation method and application thereof | |
| CN111138184A (en) | Carbon composite cerium-doped manganese-zinc ferrite wave-absorbing material and preparation method thereof | |
| CN112280533B (en) | Preparation method of ternary composite wave-absorbing material with hollow structure | |
| CN112391833B (en) | Light high-efficiency wave-absorbing material SnFe 2 O 4 /C composite nanofiber, wave-absorbing coating and preparation method | |
| CN111154259B (en) | Halloysite-cerium doped manganese zinc ferrite composite wave-absorbing material and preparation method thereof | |
| CN103864424B (en) | A kind of preparation method of microwave dielectric ceramic materials | |
| CN115595529B (en) | Preparation method of titanium silicon carbide/AT 13 high-temperature wave-absorbing coating |
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 |