CN107382283A - The dry-pressing preparation method of magnesia ceramics - Google Patents
The dry-pressing preparation method of magnesia ceramics Download PDFInfo
- Publication number
- CN107382283A CN107382283A CN201710793213.8A CN201710793213A CN107382283A CN 107382283 A CN107382283 A CN 107382283A CN 201710793213 A CN201710793213 A CN 201710793213A CN 107382283 A CN107382283 A CN 107382283A
- Authority
- CN
- China
- Prior art keywords
- magnesia
- dry
- magnesia ceramics
- ceramics
- powder
- 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
- C04B35/01—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
- C04B35/03—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 magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
- C04B35/04—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 magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
-
- 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
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
-
- 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
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
-
- 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
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/62695—Granulation or pelletising
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
The invention belongs to metallurgical technology field, and in particular to a kind of dry-pressing preparation method of magnesia ceramics.The problem of magnesia ceramics operation is tediously long, production cost is high is prepared for existing method, the present invention provides a kind of dry-pressing preparation method of magnesia ceramics, comprises the following steps：A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into certain fineness after magnetic separation；B, magnesia powder is granulated using air-flow comminution granulation；C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics is obtained after terminating.The present invention obtains the higher semi-finished product of density by controlling pressing conditions, then controls sintering condition, is prepared that density is high, hardness is big, the good magnesia ceramics of compactness.The inventive method production link is few, and production cost is low, and a kind of easy method is provided for the preparation of magnesia ceramics.
Description
Technical field
The invention belongs to metallurgical technology field, and in particular to a kind of dry-pressing preparation method of magnesia ceramics.
Background technology
Magnesia ceramics belongs to cubic system, and fusing point compares volume under 2800 DEG C or so, Mohs' hardness 5-6, high temperature
Resistance value is higher, there is good insulating properties.The high-temperature stability of magnesia ceramics, decay resistance are better than aluminium oxide ceramics, can
To be used under strong alkali corrosive atmosphere.For example made pottery applied to sodium-sulphur battery Beta aluminum oxide (β-Al2O3) solid
The high temperature sintering of porcelain electrolytic tube, alkali resistance is corroded at high temperature for it, service life length, it is normal can effectively to make up the high temperature such as corundum
Advise the deficiency that refractory material is applied in some harsh hot environments.In addition, when being contacted with many metals chemistry does not occur for magnesia
Reaction, in an inert atmosphere, even if temperature is up to 1800 DEG C, magnesia does not also react with metals such as nickel, molybdenum, niobiums.Therefore,
Magnesia tube, crucible can be used for the various steel alloys of melting, high temperature alloy without polluting alloy solution.
Magnesia ceramic articles are mostly purity or the relatively low product of consistency on domestic market, for refractory material,
Ceramic crucible and protecting tube etc..Patent 200810156563.4 discloses a kind of steel making oxygen magnesia refractories
And construction method, its product content of magnesia are 93%-95%, density<3g/cm3.Patent 201010281144.0 discloses
A kind of preparation method of high density magnesia ceramic, using nanoscale high-purity alkali type magnesium carbonate, by calcining, being molded, sintering and obtain
Magnesia ceramics is obtained, it is higher to ingredient requirement.Patent 201010563871.6 provides one kind and uses Gel-casting process system
The method of standby high density magnesia ceramic, its technique is relative complex, to use more organic matter.High purity magnesium oxide ceramics have
High temperature resistant, it is corrosion-resistant the advantages that, but the more difficult dense sintering of high purity magnesium oxide ceramics, the use of high-purity light magnesium oxide is original
Material, because its bulk density is low, reactivity is strong so that powder processed, form certain difficulty, particularly prepare the big chi of high-compactness
Phenomena such as very little magnesia tube, crucible are easily deformed, ftractureed.
The content of the invention
The technical problem to be solved in the present invention is：Existing method prepare magnesia ceramics operation it is tediously long, production cost is high
Problem.
The present invention solve technical problem technical scheme be：A kind of dry-pressing preparation method of magnesia ceramics, the party are provided
Method is simple to operate, and production cost is low, and the magnesia ceramics purity height of preparation, compactness are good, can be widely used in refractory material, pottery
The fields such as porcelain crucible.
The invention provides a kind of dry-pressing preparation method of magnesia ceramics, comprise the following steps：
A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into certain fineness after magnetic separation；
B, magnesia powder is granulated using air-flow comminution granulation；
C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；
D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics is obtained after terminating.
Wherein, in the dry-pressing preparation method of above-mentioned magnesia ceramics, magnetic field intensity is 0.5- during magnetic separation described in step a
2T。
Wherein, in the dry-pressing preparation method of above-mentioned magnesia ceramics, the certain fineness described in step a is 350-400 mesh.
Wherein, in the dry-pressing preparation method of above-mentioned magnesia ceramics, the air-flow granulation conditions described in step b are：Vacuum
Spend 0.1-0.3pa, air-flow velocity 3-5L/min.
Wherein, in the dry-pressing preparation method of above-mentioned magnesia ceramics, compressing condition is described in step c：Compacting
20-60 DEG C of temperature, pressing pressure 0.1-2Mpa, press time 10-30min.
Wherein, in the dry-pressing preparation method of above-mentioned magnesia ceramics, the sintering condition described in step d is：Sintering temperature
1100-1300 DEG C, sintering time 1-6h.
Compared with prior art, beneficial effects of the present invention are：The present invention provides a kind of dry-pressing of magnesia ceramics and prepared
Method, the impurity in magnetic separation removal magnesia is first passed through, makes magnesia purity higher, then enter using air-flow comminution granulation to magnesia
Row is granulated, and the magnesia powder after granulation is more convenient for compressing and sintered, it is possible to increase sintering character；The present invention directly uses powder
Magnesia powder is pressed last press, by controlling pressing conditions, can obtain the higher semi-finished product of density, then pass through
Sintering condition is controlled, is prepared that density is high, hardness is big, the good magnesia ceramics of compactness.The dry-pressing of the present invention prepares oxidation
The method of magnesium reduces production link, reduces production cost, it is suitable also to reach hot pressing method for preparing without using paraffin and aluminum oxide
Effect, provide more easy method for the preparation of magnesia ceramics.
Embodiment
The invention provides a kind of dry-pressing preparation method of magnesia ceramics, comprise the following steps：
A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into 350-400 mesh powders after magnetic separation；The magnetic during magnetic separation
Field intensity is 0.5-2T；
B, magnesia powder is granulated using air-flow comminution granulation；It is granulated time control comminutor vacuum 0.1-0.3pa, air-flow stream
Speed is 3-5L/min；
C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；20-60 DEG C of press temperature,
Pressing pressure is 0.1-2Mpa, press time 10-30min；
D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics is obtained after terminating；Sintering temperature
1100-1300 DEG C, sintering time 1-6h.
In the present invention, in order to reduce the impurity in magnesia, magnetic separation is first carried out using electromagnetic separator, magnetic separation can remove
The impurity such as substantial amounts of calcium, Fe, Zn, substantially can be by three oxygen in magnesia especially when magnet separator magnetic field intensity is 0.5-2T
Change two iron to remove totally, so as to reduce the influence to magnesia sintering, magnesia ceramics has higher insulating properties and high temperature resistant
Property.
Further, the present invention is by magnesia ball milling into 350-400 mesh powders, and the magnesia under this particle diameter is superfine, energy
Enough increase the density of magnesia ceramics, so as to improve the service life of magnesia ceramic articles and requirement.
The present invention is first granulated using air-flow comminution granulation to magnesia powder, and the magnesia powder after granulation is more suitable for being pressed into
Type, powder compaction press is directly used during compacting, product is easily molded, efficiency high, and the magnesia ceramics density after compacting is high, is used
Life, performance is more preferably.The present invention uses air-flow comminution granulation, avoids using paraffin, has saved production cost, simplifies behaviour
Make；And it is further cost-effective without be protected using aluminum oxide during sintering after powder compaction press compacting, it is simplified
Operation.
The present invention gets up above-mentioned all combinations of features, together provides a kind of dry-pressing system of brand-new magnesia ceramics
The magnesia ceramics that purity is higher, compactness is more preferable, hardness is bigger can be made in Preparation Method, this method, while simple to operate, raw
It is low to produce cost, suitable industrialized production.
Explanation will be further explained to the embodiment of the present invention by embodiment below, but do not indicated that this
The protection domain of invention is limited in described in embodiment in scope.
Embodiment 1 prepares magnesia ceramics using the inventive method
Specific operating procedure is as follows：
A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into 350 mesh powders after magnetic separation；Magnetic field is strong during the magnetic separation
Spend for 0.5T；
B, magnesia powder is granulated using air-flow comminution granulation；Time control comminutor vacuum 0.1pa is granulated, air-flow velocity is
3L/min；
C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；20 DEG C of press temperature, compacting
Pressure is 0.1Mpa, press time 10min；
D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics 1 is obtained after terminating；Sintering temperature
1100 DEG C, sintering time 1h.
Embodiment 2 prepares magnesia ceramics using the inventive method
Specific operating procedure is as follows：
A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into 400 mesh powders after magnetic separation；Magnetic field is strong during the magnetic separation
Spend for 2T；
B, magnesia powder is granulated using air-flow comminution granulation；Time control comminutor vacuum 0.3pa is granulated, air-flow velocity is
5L/min；
C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；60 DEG C of press temperature, compacting
Pressure is 2Mpa, press time 30min；
D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics 2 is obtained after terminating；Sintering temperature
1300 DEG C, sintering time 6h.
Embodiment 3 prepares magnesia ceramics using the inventive method
Specific operating procedure is as follows：
A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into 400 mesh powders after magnetic separation；Magnetic field is strong during the magnetic separation
Spend for 1T；
B, magnesia powder is granulated using air-flow comminution granulation；Time control comminutor vacuum 0.2pa is granulated, air-flow velocity is
4L/min；
C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；40 DEG C of press temperature, compacting
Pressure is 1Mpa, press time 20min；
D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics 3 is obtained after terminating；Sintering temperature
1200 DEG C, sintering time 3h.
Performance measurement is carried out to magnesia ceramics prepared by embodiment 1-3, obtains result of the test as shown in table 1 below.
Magnesia ceramics performance prepared by the distinct methods of table 1
Magnesia purity % consistency g/cm3 Mohs' hardness
Embodiment 1 98.3 4.0 6.1
Embodiment 2 98.2 4.1 6.0
Embodiment 3 98.9 4.4 6.3
From embodiment result, using the dry process of the present invention, purity can be prepared higher than 98%, consistency is higher than 4
G/cm3, Mohs' hardness are higher than 6 magnesia ceramics, higher compared to the magnesia ceramics purity of existing method preparation, finer and close,
Hardness is bigger, can increase the service life, and widens using field, has obvious economic benefit.
Claims (6)
1. the dry-pressing preparation method of magnesia ceramics, it is characterised in that comprise the following steps：
A, magnesia powder is subjected to magnetic separation through electromagnetic separator, ball milling is into certain fineness after magnetic separation；
B, magnesia powder is granulated using air-flow comminution granulation；
C, the magnesium oxide particle after granulation is used into powder compaction press, compressing obtained semi-finished product；
D, the semi-finished product obtained by step c are put into sintering furnace and sintered, magnesia ceramics is obtained after terminating.
2. the dry-pressing preparation method of magnesia ceramics according to claim 1, it is characterised in that：Magnetic separation described in step a
When magnetic field intensity be 0.5-2T.
3. the dry-pressing preparation method of magnesia ceramics according to claim 1, it is characterised in that：One described in step a
It is 350-400 mesh to determine fineness.
4. the dry-pressing preparation method of magnesia ceramics according to claim 1, it is characterised in that：Gas described in step b
Flowing granulation conditions is：Vacuum 0.1-0.3pa, air-flow velocity 3-5L/min.
5. the dry-pressing preparation method of magnesia ceramics according to claim 1, it is characterised in that：Suppressed described in step c
The condition of shaping is：20-60 DEG C of press temperature, pressing pressure 0.1-2Mpa, press time 10-30min.
6. the dry-pressing preparation method of magnesia ceramics according to claim 1, it is characterised in that：Burning described in step d
Knot condition is：1100-1300 DEG C of sintering temperature, sintering time 1-6h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710793213.8A CN107382283A (en) | 2017-09-06 | 2017-09-06 | The dry-pressing preparation method of magnesia ceramics |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710793213.8A CN107382283A (en) | 2017-09-06 | 2017-09-06 | The dry-pressing preparation method of magnesia ceramics |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107382283A true CN107382283A (en) | 2017-11-24 |
Family
ID=60351354
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710793213.8A Pending CN107382283A (en) | 2017-09-06 | 2017-09-06 | The dry-pressing preparation method of magnesia ceramics |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107382283A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108341659A (en) * | 2018-03-05 | 2018-07-31 | 福建省德化县驰宇陶瓷有限公司 | A kind of manufacture craft of magnesia dry-pressing ceramic products |
| CN108929104A (en) * | 2018-09-20 | 2018-12-04 | 福建省德化县驰宇陶瓷有限公司 | A kind of technique making dry-pressing ceramic products |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1153899A1 (en) * | 2000-05-02 | 2001-11-14 | Michael Cohen | Alumina ceramic products |
| CN101948299A (en) * | 2010-09-14 | 2011-01-19 | 西南科技大学 | Preparation method of compact magnesia ceramics by sintering |
| CN102822113A (en) * | 2010-05-20 | 2012-12-12 | 达泰豪化学工业株式会社 | Sintered magnesium oxide material, and process for production thereof |
| CN103415486A (en) * | 2011-03-24 | 2013-11-27 | 达泰豪化学工业株式会社 | Process for producing sintered magnesium oxide material |
| CN103601473A (en) * | 2013-11-04 | 2014-02-26 | 中国科学院合肥物质科学研究院 | High-purity high-density magnesium-oxide ceramic and preparation method thereof |
| CN105384428A (en) * | 2015-11-10 | 2016-03-09 | 上海卡贝尼精密陶瓷有限公司 | 99%-above alumina granulating powder and preparation method thereof |
-
2017
- 2017-09-06 CN CN201710793213.8A patent/CN107382283A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1153899A1 (en) * | 2000-05-02 | 2001-11-14 | Michael Cohen | Alumina ceramic products |
| CN102822113A (en) * | 2010-05-20 | 2012-12-12 | 达泰豪化学工业株式会社 | Sintered magnesium oxide material, and process for production thereof |
| CN101948299A (en) * | 2010-09-14 | 2011-01-19 | 西南科技大学 | Preparation method of compact magnesia ceramics by sintering |
| CN103415486A (en) * | 2011-03-24 | 2013-11-27 | 达泰豪化学工业株式会社 | Process for producing sintered magnesium oxide material |
| CN103601473A (en) * | 2013-11-04 | 2014-02-26 | 中国科学院合肥物质科学研究院 | High-purity high-density magnesium-oxide ceramic and preparation method thereof |
| CN105384428A (en) * | 2015-11-10 | 2016-03-09 | 上海卡贝尼精密陶瓷有限公司 | 99%-above alumina granulating powder and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 阮美娟 等: "《饮料工艺学》", 31 January 2013, 中国轻工业出版社 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108341659A (en) * | 2018-03-05 | 2018-07-31 | 福建省德化县驰宇陶瓷有限公司 | A kind of manufacture craft of magnesia dry-pressing ceramic products |
| CN108341659B (en) * | 2018-03-05 | 2020-09-04 | 福建省德化县驰宇陶瓷有限公司 | Process for manufacturing magnesium oxide dry-pressed porcelain product |
| CN108929104A (en) * | 2018-09-20 | 2018-12-04 | 福建省德化县驰宇陶瓷有限公司 | A kind of technique making dry-pressing ceramic products |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103601473B (en) | A kind of high purity, high-compactness magnesia ceramics | |
| CN103011865B (en) | Ventilated brick and preparation method thereof | |
| CN101948299B (en) | Preparation method of compact magnesia ceramics by sintering | |
| CN103304239A (en) | TiB2-based metal ceramic material for aluminium cell and preparation method of material | |
| CN107417260A (en) | The hot pressing method for preparing of magnesia ceramics | |
| CN106800420A (en) | A kind of silicon carbide whisker in-situ composite corindon high-temperature ceramic materials and preparation method thereof | |
| CN109369181B (en) | Volume-stable high-purity zirconia refractory product | |
| CN108585803B (en) | Preparation method of ring-formation-free pellet rotary kiln lining | |
| CN101555150A (en) | Low-carbon magnesia carbon brick containing nanometer zinc oxide | |
| CN107382283A (en) | The dry-pressing preparation method of magnesia ceramics | |
| CN101891408B (en) | Method for preparing magnesia-alumina spinel-containing aluminate cement | |
| CN105906356A (en) | Method for preparing high-purity hydration-resisting calcium oxide crucible | |
| CN103194631B (en) | Preparation method of high-volume fraction alumina ceramic particle enhanced composite material | |
| KR100704842B1 (en) | Crucibles and rare earth alloys for melting rare earth alloys | |
| CN107540391A (en) | A kind of preparation method of high-strength compact zirconium oxide forsterite composite | |
| CN107043265A (en) | A kind of metallurgical, coloured smelting furnace is not with burning magnesite-chrome brick and preparation method thereof | |
| CN110713380A (en) | Preparation method of high-purity compact forsterite | |
| CN107324796B (en) | A kind of carbon/magnesium aluminate spinel composite powder | |
| CN107417271A (en) | A kind of preparation method of the bar-shaped brilliant enhancing dimension stone of magnesia alumina spinel of rare earth aluminium (silicon) hydrochlorate | |
| CN104003736B (en) | A kind of preparation method of slide brick | |
| Tang et al. | Influence of powder characteristics on the sintering behaviour of reactive alumina powders | |
| CN115925427A (en) | Preparation method of aluminum nitride ceramic complex crucible for titanium alloy induction melting | |
| CN108516804A (en) | The preparation method of extrusion type magnesia tube | |
| CN107399959B (en) | A kind of preparation method of alumina-magnesia-calcia composite material enhanced by nano-oxide | |
| CN1943920B (en) | Method for producing low pressure cast aluminum liquid lift pipe |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20171124 |