CN113735603A - High-performance coating material for intermediate frequency furnace - Google Patents
High-performance coating material for intermediate frequency furnace Download PDFInfo
- Publication number
- CN113735603A CN113735603A CN202111178212.5A CN202111178212A CN113735603A CN 113735603 A CN113735603 A CN 113735603A CN 202111178212 A CN202111178212 A CN 202111178212A CN 113735603 A CN113735603 A CN 113735603A
- Authority
- CN
- China
- Prior art keywords
- intermediate frequency
- frequency furnace
- micro powder
- white corundum
- performance 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/10—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
- C04B35/101—Refractories from grain sized mixtures
- C04B35/105—Refractories from grain sized mixtures containing chromium oxide or chrome ore
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/44—Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate
- C04B2235/449—Organic acids, e.g. EDTA, citrate, acetate, oxalate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Ceramic Products (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention relates to a high-performance coating for an intermediate frequency furnace, which comprises the following components in percentage by weight: 50-60% of fused white corundum particles, 20-35% of white corundum fine powder, 0-10% of alumina micro powder, 0-10% of clay, 0-8% of silica micro powder, 0-3% of chromium oxide micro powder, 0-1% of plasticizer, 1-5% of composite additive and 10% of aluminum dihydrogen phosphate liquid binder; the compound additive consists of citric acid and oxalic acid. According to the invention, the composite additive consisting of citric acid and oxalic acid is added, so that the pH value of the coating material is effectively adjusted, the quality guarantee period of the coating material is prolonged, the high-temperature strength of the coating material is enhanced, and the service life of the furnace lining of the intermediate frequency furnace is prolonged.
Description
Technical Field
The invention relates to the technical field of unshaped refractory materials, in particular to a high-performance coating material for an intermediate frequency furnace.
Background
The intermediate frequency furnace is a power supply device for converting power frequency 50Hz alternating current into intermediate frequency (300-2000 Hz). Firstly, rectifying three-phase power frequency alternating current to form direct current, then converting the direct current into adjustable intermediate frequency current to be supplied to an induction coil, generating a strong magnetic field in the electrified coil, and heating a furnace burden body by utilizing an electromagnetic induction principle; according to the principle of electromagnetic effect, high-density magnetic lines generated in the induction coil can penetrate through non-metallic substances, cut metal materials contained in the induction coil, generate large eddy currents in the metal materials and instantly generate induction heating on the metal in a non-contact mode, so that metal furnace burden is melted.
The intermediate frequency furnace has the characteristics of high heating speed, high production efficiency, less oxidation and decarburization, material and cost saving, uniform heating, high temperature control precision and the like; in addition, compared with other smelting furnaces, the medium frequency furnace has the greatest advantage of being capable of recovering precious metals in metal furnace charges, effectively avoiding element burning loss in the smelting process of steel or alloy materials, and being an ideal resource recycling mode.
The inner side of a furnace lining material of the medium-frequency induction furnace is filled with high-temperature molten metal, the periphery of the furnace lining material is provided with a water-cooling induction coil, and the temperature of the furnace wall is sharply reduced after the molten metal is discharged from the furnace each time; the furnace lining material not only needs to bear shock of shock cooling and shock heating, but also needs to bear the scouring of molten metal which moves continuously due to electromagnetic stirring in the smelting process and the erosion of furnace slag; therefore, strict requirements are imposed on the selection and use of the lining material.
Disclosure of Invention
The invention provides a high-performance coating material for an intermediate frequency furnace, which is characterized in that a composite additive consisting of citric acid and oxalic acid is added to effectively adjust the pH value of the coating material, so that the quality guarantee period of the coating material can be prolonged, the high-temperature strength of the coating material can be enhanced, and the service life of a furnace lining of the intermediate frequency furnace is prolonged.
In order to achieve the purpose, the invention adopts the following technical scheme:
a high-performance coating material for an intermediate frequency furnace comprises the following components in percentage by weight: 50-60% of fused white corundum particles, 20-35% of white corundum fine powder, 0-10% of alumina micro powder, 0-10% of clay, 0-8% of silica micro powder, 0-3% of chromium oxide micro powder, 0-1% of plasticizer, 1-5% of composite additive and 10% of aluminum dihydrogen phosphate liquid binder; the compound additive consists of citric acid and oxalic acid.
The electric melting white corundum particles are formed by mixing 3 kinds of particles with the particle sizes of 5-3 mm, 3-1 mm and 1-0 mm according to any proportion; the granularity of the white corundum fine powder is 325 meshes; the physical and chemical performance indexes of the fused white corundum particles and the white corundum fine powder are as follows: al (Al)2O3≥60%、TiO2≥2.5%、Fe2O3≤1.5%、R2O≤0.3%。
The alumina micro powder is alpha-alumina micro powder with the granularity of 1-3 mu m; the physicochemical property index of the alpha-alumina micro powder is Al2O3≥99.0%、Fe2O3≤0.04%、R2O≤0.3%、SiO2≤0.1%。
The physical and chemical performance indexes of the silicon micro powder are as follows: SiO 22≥92%,Fe2O3≤0.1%。
The physical and chemical performance indexes of the aluminum dihydrogen phosphate liquid binding agent are as follows: p2O5≥33%,Al2O3≥8.5%,Fe2O3Less than or equal to 0.01, pH value of 1.5-2.5 and specific gravity of 1.467-1.47.
The plasticizer is methyl cellulose.
The clay is Guangxi white clay with the granularity of 200 meshes.
The compound additive comprises the following components in percentage by weight: 1-99% of citric acid and 1-99% of oxalic acid.
Compared with the prior art, the invention has the beneficial effects that:
the composite additive consisting of citric acid and oxalic acid is adopted, the citric acid and the oxalic acid have different acidity, and the pH value of the coating can be effectively adjusted after the citric acid and the oxalic acid are compounded, so that the quality guarantee period of the coating is prolonged, the high-temperature strength of the coating is enhanced, and the service life of a furnace lining of the intermediate frequency furnace is prolonged.
Detailed Description
The invention relates to a high-performance coating material for an intermediate frequency furnace, which comprises the following components in percentage by weight: 50-60% of fused white corundum particles, 20-35% of white corundum fine powder, 0-10% of alumina micro powder, 0-10% of clay, 0-8% of silica micro powder, 0-3% of chromium oxide micro powder, 0-1% of plasticizer, 1-5% of composite additive and 10% of aluminum dihydrogen phosphate liquid binder; the compound additive consists of citric acid and oxalic acid.
The electric melting white corundum particles are formed by mixing 3 kinds of particles with the particle sizes of 5-3 mm, 3-1 mm and 1-0 mm according to any proportion; the granularity of the white corundum fine powder is 325 meshes; the physical and chemical performance indexes of the fused white corundum particles and the white corundum fine powder are as follows: al (Al)2O3≥60%、TiO2≥2.5%、Fe2O3≤1.5%、R2O≤0.3%。
The alumina micro powder is alpha-alumina micro powder with the granularity of 1-3 mu m; the physicochemical property index of the alpha-alumina micro powder is Al2O3≥99.0%、Fe2O3≤0.04%、R2O≤0.3%、SiO2≤0.1%。
The physical and chemical performance indexes of the silicon micro powder are as follows: SiO 22≥92%,Fe2O3≤0.1%。
The physical and chemical performance indexes of the aluminum dihydrogen phosphate liquid binding agent are as follows: p2O5≥33%,Al2O3≥8.5%,Fe2O3Less than or equal to 0.01, pH value of 1.5-2.5 and specific gravity of 1.467-1.47.
The plasticizer is methyl cellulose.
The clay is Guangxi white clay with the granularity of 200 meshes.
The compound additive comprises the following components in percentage by weight: 1-99% of citric acid and 1-99% of oxalic acid.
The following examples are carried out on the premise of the technical scheme of the invention, and detailed embodiments and specific operation processes are given, but the scope of the invention is not limited to the following examples.
[ example 1 ]
In the embodiment, the high-performance coating for the intermediate frequency furnace comprises the following components in percentage by weight: 55% of white corundum particles, wherein the granularity is 10% of 5-3 mm, 20% of 3-1 mm and 25% of 1-0 mm; 28.5 percent of white corundum fine powder with the granularity of 200 meshes, 8 percent of alumina micro powder, 5 percent of silicon micro powder, 1 percent of chromium oxide micro powder, 0.5 percent of methyl cellulose and 2 percent of composite additive (wherein 1 percent of citric acid and 1 percent of oxalic acid).
The mixture prepared according to the proportion is stirred for 2 minutes, 8 percent of aluminum dihydrogen phosphate is added and then stirred for 3 minutes, the mixture is molded into a sample block with the size of 40mm multiplied by 160mm by vibration casting, the sample block is maintained for 24 hours, baked for 24 hours at the temperature of 110 ℃, baked for 3 hours at the temperature of 1450 ℃ in a high-temperature furnace, and the temperature is preserved for 0.5 hour at the temperature of 1400 ℃.
And sealing the rest pug, storing in shade, and observing the shelf life.
The product performance test results are shown in table 1.
TABLE 1
Bulk density after baking at 110 ℃ for 24h | 2.71g/cm3 |
Cold bending strength at 110 deg.c for 24 hr after baking | 4.4Mpa |
Cold state compression strength after baking at 110 deg.C for 24h | 19Mpa |
Cold fracture strength at 1450 deg.C for 3 hr after firing | 14.1Mpa |
Cold state compression strength at 1450 deg.C for 3h | 40.2Mpa |
Permanent line change rate after 1450 ℃ x 3h firing | -0.1% |
High-temperature rupture strength of 1400 ℃ for 0.5h | 0.3Mpa |
Shelf life/day | 60 |
[ example 2 ]
In the embodiment, the high-performance coating for the intermediate frequency furnace comprises the following components in percentage by weight: 55% of white corundum particles, wherein the granularity is 12% of 5-3 mm, 20% of 3-1 mm and 23% of 1-0 mm; 28.5 percent of white corundum fine powder with the granularity of 200 meshes, 8 percent of alumina micro powder, 5 percent of silicon micro powder, 1 percent of chromium oxide micro powder, 0.5 percent of methyl cellulose and 2 percent of composite additive (wherein, 1.5 percent of citric acid and 0.5 percent of oxalic acid).
The mixture prepared according to the proportion is stirred for 2 minutes, 8 percent of aluminum dihydrogen phosphate is added and then stirred for 3 minutes, the mixture is molded into a sample block with the size of 40mm multiplied by 160mm by vibration casting, the sample block is maintained for 24 hours, baked for 24 hours at the temperature of 110 ℃, baked for 3 hours at the temperature of 1450 ℃ in a high-temperature furnace, and the temperature is preserved for 0.5 hour at the temperature of 1400 ℃.
And sealing the rest pug, storing in shade, and observing the shelf life.
The results of the product property measurements are shown in Table 2.
TABLE 2
Bulk density after baking at 110 ℃ for 24h | 2.77g/cm3 |
Cold bending strength at 110 deg.c for 24 hr | 3.5Mpa |
Cold state compression strength at 110 deg.c for 24 hr | 22Mpa |
Cold fracture strength at 1450 deg.C for 3 hr after burning | 16Mpa |
Cold state compression strength at 1450 deg.C for 3h after burning | 50.9Mpa |
Permanent line change rate after 1450 deg.C x 3h burning | -0.3% |
High-temperature rupture strength of 1400 ℃ for 0.5h | 0.5Mpa |
Shelf life/day | 60 |
[ example 3 ]
In the embodiment, the high-performance coating for the intermediate frequency furnace comprises the following components in percentage by weight: 55% of white corundum particles, wherein the granularity is 10% of 5-3 mm, 25% of 3-1 mm and 20% of 1-0 mm; 28.5 percent of white corundum fine powder with the granularity of 200 meshes, 8 percent of alumina micro powder, 5 percent of silicon micro powder, 1 percent of chromium oxide micro powder, 0.5 percent of methyl cellulose and 2 percent of composite additive (wherein, 0.5 percent of citric acid and 1.5 percent of oxalic acid).
The mixture prepared according to the proportion is stirred for 2 minutes, 8 percent of aluminum dihydrogen phosphate is added and then stirred for 3 minutes, the mixture is molded into a sample block with the size of 40mm multiplied by 160mm by vibration casting, the sample block is maintained for 24 hours, baked for 24 hours at the temperature of 110 ℃, baked for 3 hours at the temperature of 1450 ℃ in a high-temperature furnace, and the temperature is maintained for 0.5 hour at the temperature of 1400 ℃.
And sealing the rest pug, storing in shade, and observing the shelf life.
The product performance test results are shown in Table 3.
TABLE 3
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (8)
1. The high-performance coating material for the intermediate frequency furnace is characterized by comprising the following components in percentage by weight: 50-60% of fused white corundum particles, 20-35% of white corundum fine powder, 0-10% of alumina micro powder, 0-10% of clay, 0-8% of silica micro powder, 0-3% of chromium oxide micro powder, 0-1% of plasticizer, 1-5% of composite additive and 10% of aluminum dihydrogen phosphate liquid binder; the compound additive consists of citric acid and oxalic acid.
2. The high-performance coating for the intermediate frequency furnace according to claim 1, wherein the electro-fused white corundum particles are formed by mixing 3 kinds of particles with the particle sizes of 5-3 mm, 3-1 mm and 1-0 mm according to any proportion; the granularity of the white corundum fine powder is 325 meshes; electric meltingThe physical and chemical performance indexes of the white corundum particles and the white corundum fine powder are as follows: al (Al)2O3≥60%、TiO2≥2.5%、Fe2O3≤1.5%、R2O≤0.3%。
3. The high-performance coating for the intermediate frequency furnace is characterized in that the alumina micro powder is alpha-alumina micro powder, and the particle size is 1-3 μm; the physicochemical property index of the alpha-alumina micro powder is Al2O3≥99.0%、Fe2O3≤0.04%、R2O≤0.3%、SiO2≤0.1%。
4. The high-performance coating for the intermediate frequency furnace as claimed in claim 1, wherein the physical and chemical performance indexes of the silicon micropowder are as follows: SiO 22≥92%,Fe2O3≤0.1%。
5. The high-performance coating for the intermediate frequency furnace as claimed in claim 1, wherein the physical and chemical performance indexes of the aluminum dihydrogen phosphate liquid binder are as follows: p2O5≥33%,Al2O3≥8.5%,Fe2O3Less than or equal to 0.01, pH value of 1.5-2.5 and specific gravity of 1.467-1.47.
6. The high-performance coating for the intermediate frequency furnace as claimed in claim 1, wherein the plasticizer is methylcellulose.
7. The high-performance coating for the intermediate frequency furnace is characterized in that the clay is Guangxi white mud with the granularity of 200 meshes.
8. The high-performance coating for the intermediate frequency furnace as claimed in claim 1, wherein the compound additive comprises the following components in percentage by weight: 1-99% of citric acid and 1-99% of oxalic acid.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111178212.5A CN113735603A (en) | 2021-10-09 | 2021-10-09 | High-performance coating material for intermediate frequency furnace |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111178212.5A CN113735603A (en) | 2021-10-09 | 2021-10-09 | High-performance coating material for intermediate frequency furnace |
Publications (1)
Publication Number | Publication Date |
---|---|
CN113735603A true CN113735603A (en) | 2021-12-03 |
Family
ID=78726278
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202111178212.5A Pending CN113735603A (en) | 2021-10-09 | 2021-10-09 | High-performance coating material for intermediate frequency furnace |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113735603A (en) |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2093012A (en) * | 1981-02-16 | 1982-08-25 | Didier Werke Ag | Refractory or heat-resistant composite articles |
CN102491769A (en) * | 2011-12-06 | 2012-06-13 | 安徽瑞泰新材料科技有限公司 | Composite bonding low-temperature constructional castable refractory |
CN102674855A (en) * | 2012-05-21 | 2012-09-19 | 中国钢研科技集团有限公司 | Plastic patching material and preparation method |
CN103755361A (en) * | 2013-12-20 | 2014-04-30 | 中钢集团洛阳耐火材料研究院有限公司 | Aluminum-chromium-silicon fireproof material |
CN110790566A (en) * | 2019-11-11 | 2020-02-14 | 贵阳明通炉料有限公司 | Superhard high-temperature ceramic matrix composite wear-resistant coating and application method thereof |
CN111704443A (en) * | 2020-07-10 | 2020-09-25 | 湖北品申科技有限公司 | Aluminum-magnesium ramming mass for intermediate frequency furnace and preparation method thereof |
CN113087499A (en) * | 2021-04-08 | 2021-07-09 | 铜陵旭时新材料科技有限公司 | Furnace mouth coil protection material of medium-frequency induction furnace and preparation method and application thereof |
-
2021
- 2021-10-09 CN CN202111178212.5A patent/CN113735603A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2093012A (en) * | 1981-02-16 | 1982-08-25 | Didier Werke Ag | Refractory or heat-resistant composite articles |
CN102491769A (en) * | 2011-12-06 | 2012-06-13 | 安徽瑞泰新材料科技有限公司 | Composite bonding low-temperature constructional castable refractory |
CN102674855A (en) * | 2012-05-21 | 2012-09-19 | 中国钢研科技集团有限公司 | Plastic patching material and preparation method |
CN103755361A (en) * | 2013-12-20 | 2014-04-30 | 中钢集团洛阳耐火材料研究院有限公司 | Aluminum-chromium-silicon fireproof material |
CN110790566A (en) * | 2019-11-11 | 2020-02-14 | 贵阳明通炉料有限公司 | Superhard high-temperature ceramic matrix composite wear-resistant coating and application method thereof |
CN111704443A (en) * | 2020-07-10 | 2020-09-25 | 湖北品申科技有限公司 | Aluminum-magnesium ramming mass for intermediate frequency furnace and preparation method thereof |
CN113087499A (en) * | 2021-04-08 | 2021-07-09 | 铜陵旭时新材料科技有限公司 | Furnace mouth coil protection material of medium-frequency induction furnace and preparation method and application thereof |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN103265297B (en) | Refining steel ladle carbon-free periclase spinel baking-free brick and preparation method thereof | |
CN105152662B (en) | Medium frequency induction furnace body dry type ramming material | |
CN108720619B (en) | Cooking utensil and preparation method thereof | |
US2695849A (en) | Fused cast refractory articles | |
CN112375953A (en) | Fe-Mn-Al-C-M multi-principal-element light high-strength alloy and preparation method thereof | |
CN103642962A (en) | Treatment method of vanadium extraction tailings | |
CN102937373A (en) | Crucible for direct current arc induction furnace and manufacturing method thereof | |
CN111004025A (en) | Component of slag adhering resisting coating for ladle lining and preparation method thereof | |
CN113735603A (en) | High-performance coating material for intermediate frequency furnace | |
CN109708475A (en) | A kind of aluminium alloy ingots melting intermediate frequency furnace furnace building process | |
CN104060183A (en) | Swing arm bracket and production method thereof | |
CN112250421A (en) | Magnesia carbon brick for impact area of converter and preparation method thereof | |
CN109020516B (en) | Novel baking-free and repairable chute | |
CN113651623B (en) | Dry-type ramming material for medium-frequency induction furnace and preparation method thereof | |
CN115819075A (en) | Low-temperature sintered titanium-rich corundum composite silicon carbide brick and preparation method thereof | |
CN113860896A (en) | High-temperature precision casting low-creep corundum mullite and manufacturing method thereof | |
CN113087499A (en) | Furnace mouth coil protection material of medium-frequency induction furnace and preparation method and application thereof | |
JP2573227B2 (en) | Dry ramming material for crucible induction furnace | |
CN103540852B (en) | A kind of aero oil refining unit discaling roll and preparation technology | |
CN105112787A (en) | Rare earth Cr-Mo-V alloy steel ball for ball mill and preparation method of rare earth Cr-Mo-V alloy steel ball | |
CN110918997A (en) | Method for preparing porous stainless steel from iron scale | |
CN111482612A (en) | Iron-silicon-aluminum metal powder for 3D printing and preparation method thereof | |
CN104120338B (en) | Method for improving oxidation resistance of precision alloy Ni36 | |
CN215090669U (en) | Special-shaped cast steel filter unit system | |
CN109402489B (en) | Ceramic reinforced iron-based composite material taking lithium feldspar and kyanite as components, preparation method thereof and mechanical part |
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 | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20211203 |
|
RJ01 | Rejection of invention patent application after publication |