CN115872746A - Magnesium fluoride composite ceramic and preparation method thereof - Google Patents
Magnesium fluoride composite ceramic and preparation method thereof Download PDFInfo
- Publication number
- CN115872746A CN115872746A CN202310002905.1A CN202310002905A CN115872746A CN 115872746 A CN115872746 A CN 115872746A CN 202310002905 A CN202310002905 A CN 202310002905A CN 115872746 A CN115872746 A CN 115872746A
- Authority
- CN
- China
- Prior art keywords
- composite ceramic
- magnesium fluoride
- fluoride
- sintering
- total content
- 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
Images
Landscapes
- Compositions Of Oxide Ceramics (AREA)
Abstract
The application relates to the field of neutron moderation, in particular to magnesium fluoride composite ceramic and a preparation method thereof. Wherein, the magnesium fluoride matrix accounts for 80-95 wt% of the total content of the composite ceramic; the addition amount of the binder is 0-1 wt% of the total content of the composite ceramic; the addition amount of the sintering aid is 0 to 10 weight percent of the total content of the composite ceramic; the sintering aid comprises at least one of lithium fluoride, calcium fluoride, aluminum fluoride and metallic aluminum. The magnesium fluoride composite ceramic and the preparation method thereof increase the probability of collision with neutrons by increasing the fluorine concentration in the composite ceramic, so that the magnesium fluoride composite ceramic has a good neutron moderating effect.
Description
Technical Field
The application relates to the field of neutron moderation, in particular to magnesium fluoride composite ceramic and a preparation method thereof.
Background
Graphite and water are commonly used thermal neutron moderators. The design of the moderator material needs to consider neutron moderation efficiency, preparation process feasibility, mechanical property, environmental friendliness and economy. For example, 39% of aluminum powder is added into the existing neutron moderator, the aluminum powder is flammable and explosive, the fluorine content in the moderator is reduced, and aluminum fluoride is volatile at high temperature and corrodes the heat insulation material of a sintering furnace, so that the aluminum fluoride moderator is harmful to human bodies and the environment, the sintering densification difficulty is high, the mechanical strength is low, and the manufacturing and using costs of the aluminum fluoride moderator are high due to the comprehensive factors.
Disclosure of Invention
To address at least one of the above and other problems, embodiments of the present application provide a magnesium fluoride composite ceramic and a method of manufacturing the same.
According to a first aspect of embodiments herein, there is provided a magnesium fluoride composite ceramic comprising: magnesium fluoride matrix, binder and sintering aid; wherein, the magnesium fluoride matrix accounts for 80-95 wt% of the total content of the composite ceramic; the addition amount of the binder is 0-1 wt% of the total content of the composite ceramic; the addition amount of the sintering aid is 0-20 wt% of the total content of the composite ceramic; the sintering aid comprises at least one of lithium fluoride, calcium fluoride, aluminum fluoride and metallic aluminum.
According to a second aspect of the embodiments of the present application, a magnesium fluoride matrix and a sintering aid are mixed and added into a mixer to obtain mixed powder; drying the mixed powder until no agglomeration exists, and sieving to obtain uniform powder; filling the uniform powder into a pressing die or an isostatic pressing die sleeve, and pressing and forming to obtain a green body; and putting the pressed green body into a sintering furnace, and sintering to obtain the magnesium fluoride product.
The magnesium fluoride composite ceramic and the preparation method thereof increase the probability of collision with neutrons by increasing the fluorine concentration in the composite ceramic, so that the magnesium fluoride composite ceramic has a good neutron moderating effect.
Drawings
FIG. 1 is a process flow diagram of an embodiment of the present application.
Detailed Description
Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. It should be understood that the description is illustrative only and is not intended to limit the scope of the present application. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the application. It may be evident, however, that one or more embodiments may be practiced without these specific details. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present application.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.
All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. It is noted that the terms used herein should be interpreted as having a meaning that is consistent with the context of this specification and should not be interpreted in an idealized or overly formal sense.
Fluoride can slow fast neutrons into epithermal neutrons, and thus has special applications in the fields of Boron Neutron Capture Therapy (BNCT) and the like. The design of the moderator material needs to consider neutron moderation efficiency, preparation process feasibility, mechanical property, environmental friendliness and economy.
The commonly used fluoride has the characteristics of easy volatilization, water solubility and the like, and may have strong toxic and side effects, may form irritant or toxic gas, or absorb water to form toxic substances, thereby easily causing damage to human bodies and equipment. Further, the fluoride itself is inferior in thermal stability and may be decomposed.
In consideration of the above problems while ensuring the fluorine content, it is considered that the fluoride used in the prior art, such as aluminum fluoride, is not an optimal solution as a neutron moderator, and it is necessary to newly select a fluoride as a substrate to obtain a new neutron moderator that can satisfy various requirements.
The magnesium fluoride has higher fluorine content and excellent neutron moderation performance, and does not generate volatile matters harmful to human bodies and the environment in the high-temperature sintering process. The hot-pressed sintered magnesium fluoride ceramic is an important infrared window and fairing material of an infrared guided missile, and the hot-pressing temperature of the magnesium fluoride ceramic is about 700 ℃. Therefore, a method using magnesium fluoride as a neutron moderator can be attempted.
The composite ceramic and the preparation method provided by the embodiment of the application are the high-density magnesium fluoride ceramic and the preparation method thereof, and the probability of collision with neutrons is increased by increasing the fluorine concentration in the composite ceramic, so that the composite ceramic has a better neutron moderating effect.
The embodiment of the application provides a magnesium fluoride composite ceramic, which comprises: magnesium fluoride matrix, binder and sintering aid.
Wherein, the magnesium fluoride matrix accounts for 80-95 wt% of the total content of the composite ceramic; the addition amount of the binder is 0-1 wt% of the total content of the composite ceramic; the addition amount of the sintering aid is 0-20 wt% of the total content of the composite ceramic. The sintering aid comprises at least one of lithium fluoride, calcium fluoride, aluminum fluoride and metallic aluminum.
Neutron moderation is achieved primarily by low atomic weight species, among others. The magnesium fluoride ceramic material is adopted as a substrate, the fluorine content of the magnesium fluoride is 61.0 percent, and the density is 3.148g/cm 3 The magnesium fluoride has the advantages of high melting point 1261 ℃, high boiling point 2260 ℃, high thermal stability, no decomposition or volatilization after being heated below the melting point, difficult water dissolution, high fluorine content, excellent neutron moderation performance and no generation of volatile matters harmful to human bodies and the environment in the high-temperature sintering process.
The proportion of magnesium fluoride in the ceramic material obtained by the method reaches more than 80%, and then additives such as simple substances or compounds composed of elements such as fluorine, aluminum, magnesium and lithium are used as dispersed phases to be added into the ceramic material. Compare in the neutron moderator who regards as continuous base member with metallic aluminum, this application is on the basis that can prepare, has considered fluorine element content in the key, and this is the main element who plays the slowing down effect, and fluorine concentration is higher, and the probability that collides with the neutron is just bigger, and the slowing down effect is better. Therefore this application compares in current neutron moderator, can play better neutron moderation effect, has the compound ceramic neutron moderator of magnesium fluoride of higher fluorine content, excellent neutron moderation performance, higher strength, environmental protection, economy, can be used to the any occasion that needs the epithermal neutron.
In some embodiments, the magnesium fluoride matrix may comprise 80wt%, 82wt%, 84wt%, 86wt%, 88wt%, 90wt%, 93wt%, 95wt% of the total composite ceramic content.
In some embodiments, the binder may be added in an amount of 0wt%, 0.2wt%, 0.4wt%, 0.6wt%, 0.8wt%, 1wt% of the total composite ceramic content.
In some embodiments, the sintering aid is selected in consideration of compatibility with the magnesium fluoride matrix, and as low as possible elemental substances with low atomic weight are used, or liquid phase sintering can be generated during the sintering process, such as metal aluminum, which melts during the sintering process to infiltrate the boundaries of powder particles, so that high density can be achieved more easily, the loading amount of fluorine element is increased, and better slowing-down effect is achieved.
In some embodiments, the lithium fluoride is added in an amount of 0 to 10wt% of the total composite ceramic content.
In some embodiments, the lithium fluoride may be added in an amount of 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% of the total composite ceramic content.
In some embodiments, the metallic aluminum is added in an amount of 0 to 10wt% of the total composite ceramic content.
In some embodiments, the amount of aluminum metal added may be 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% of the total composite ceramic content.
The fluorine content of the lithium fluoride was 71%, and the density was 2.64g/cm 3 Melting point of 848 deg.C, boiling point of 1681 deg.C, and saturated steaming at 1047 deg.CThe vapor pressure is 0.133kPa, the lithium volatilizes at the temperature of over 1100 ℃, the thermal neutron absorption cross section of the lithium reaches up to 71barn, the lithium fluoride is slightly soluble in water, is easy to absorb moisture, is highly toxic, irritant and high in price.
The metal aluminum and the lithium fluoride can generate liquid phase sintering in the sintering process, can be melted in the sintering process, infiltrate the powder particle boundary, and can more easily achieve high density, improve the loading capacity of fluorine element and achieve better slowing-down effect.
In some embodiments, the calcium fluoride is added in an amount of 0 to 10wt% of the total composite ceramic content.
In some embodiments, the calcium fluoride may be added in an amount of 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% of the total content of the composite ceramic.
In some embodiments, the aluminum fluoride is added in an amount of 0 to 5wt% of the total composite ceramic content.
In some embodiments, the amount of aluminum fluoride added may be 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt% of the total composite ceramic content.
The anhydrous aluminum fluoride has a fluorine content of 67.8% and a density of 2.88g/cm 3 The melting point is 1040 ℃, the saturated vapor pressure at 1238 ℃ is 0.13kPa, the aluminum fluoride is very volatile at high temperature, and can react with water vapor to form hydrogen fluoride and aluminum oxide when heated to 300-400 ℃, and the hydrogen fluoride gas has strong toxic and side effects on human bodies and equipment, so the preparation of the aluminum fluoride ceramic is not environment-friendly.
The fluorine content of the calcium fluoride is low, is only 48.6 percent, and the density is 3.18g/cm 3 Melting point of 1423 ℃ and boiling point of 2500g/cm 3 The thermal stability is very good.
The calcium fluoride and the aluminum fluoride promote the inter-granular substance migration in the sintering process, accelerate the process of discharging the air holes in the substances and improve the density.
In some embodiments, the binder is polyvinyl butyral (PVB) or polyvinylpyrrolidone (PVP).
Fig. 1 is a process flow diagram of an embodiment of the present application, and referring to fig. 1, an embodiment of the present application further provides a method of preparing a magnesium fluoride composite ceramic, including:
s100: and (3) wet mixing: mixing a magnesium fluoride matrix and a sintering aid, and adding into a mixer to obtain mixed powder; s200: drying and sieving: drying the mixed powder until no agglomeration exists, and sieving to obtain uniform powder; s300: and (3) compression molding: filling the uniform powder into a pressing die or an isostatic pressing die sleeve, and pressing and forming to obtain a green body; s400: pressureless sintering: and putting the pressed green body into a sintering furnace, and sintering to obtain a magnesium fluoride product.
The proportion of magnesium fluoride in the ceramic material obtained by the method reaches more than 80%, and then additives such as simple substances or compounds composed of elements such as fluorine, aluminum, magnesium and lithium are used as dispersed phases to be added into the ceramic material. Compared with a neutron moderator taking metal aluminum as a continuous matrix, the neutron moderator takes the fluorine content into consideration on the basis of preparation, the fluorine content is a main element for moderation, the higher the fluorine concentration is, the higher the probability of collision with neutrons is, and the better the moderation effect is. Therefore this application compares in current neutron moderator, can play better neutron moderation effect, has the compound ceramic neutron moderator of magnesium fluoride of higher fluorine content, excellent neutron moderation performance, higher strength, environmental protection, economy, can be used to the any occasion that needs the epithermal neutron.
In some embodiments, the magnesium fluoride matrix is mixed with a sintering aid and added to the mixer, further comprising: adding grinding balls according to a ball-material ratio of 3.
In some embodiments, the ball-to-feed ratio of the grinding ball to the mixture of the magnesium fluoride matrix and the sintering aid may be 3.
In some embodiments, the drying temperature of the mixed powder is 60 ℃ to 75 ℃, the drying environment is vacuum, and the vacuum degree is lower than 10Pa.
In some embodiments, the compression molding may be a dynamic compression process, wherein the steel die pressure in the dynamic compression process is 250MPa to 500MPa, and the pressure is maintained for 10min.
In some embodiments, the compression molding can also be a static compression process, wherein the isostatic pressure of the static compression process is 50-200 MPa, and the pressure is maintained for 30m.
In some embodiments, placing the pressed green body into a sintering furnace comprises: the sintering temperature is 800-1100 ℃, the heat preservation time is 2-6 h, and the sintering atmosphere is argon.
In some embodiments, the pressed green body is placed in a sintering furnace, and the method further comprises a cooling process, wherein the cooling process is carried out at a constant cooling speed of 1-5 ℃/min. The product can be effectively prevented from cracking through uniform cooling.
Obtaining a green body with large size, high density and uniform density distribution by dynamic pressing forming or isostatic static pressing forming of a steel die; and finally, carrying out pressureless sintering in the inert gas protection to obtain the high-density magnesium fluoride composite ceramic.
In some embodiments, further comprising: and (3) performing mechanical grinding and surface polishing on the magnesium fluoride product.
The technical solutions of the present application are described in detail by the following preferred embodiments, and it should be noted that the following specific embodiments are only examples and are not intended to limit the present application.
Example 1: and (4) preparing a sample.
Sample 1:
MgF 2 +1% LiF +10% Al powder, adding milling balls at a ball-to-material ratio of 3. Drying at 60 deg.C under vacuum condition with vacuum degree lower than 10Pa and 50MPa, cold isostatic pressing, and maintaining for 30min. Sintering at 1000 deg.C under argon protection for 3 hr, cooling rate of 1 deg.C/min, density of 96.46% and T.D. The fluorine content in sample 1 was found to be 55% by calculation.
Sample 2:
MgF 2 +2％CaF 2 +3％AlF 3 +5% of Al powder, the milling balls were added at a ball-to-mass ratio of 8, the mixing medium was ethanol, the mixing time was 10 hours, and the rotation speed was 200rpm. Drying at 75 deg.C under vacuum condition with vacuum degree lower than 10Pa and 100MPa, cold isostatic pressing, maintaining pressure for 30min, sintering at 900 deg.C under argon protection for 5 hr, cooling, and sintering under reduced pressureRate 5 ℃/min, density 97.16% t.d. The fluorine content in sample 2 was found to be 57.9% by calculation.
Sample 3:
MgF 2 +2％LiF+5％AlF 3 +10% of Al powder, the milling balls were added at a ball-to-mass ratio of 5. Drying at 70 deg.C under vacuum degree of 10Pa below 10 MPa, compression molding at 500MPa for 10min, sintering at 950 deg.C under argon protection for 4 hr, cooling at 3 deg.C/min, and making the density 96.78% T.D. The fluorine content in sample 3 was found to be 56.7% by calculation.
Sample 4:
MgF 2 +1％LiF+2％CaF 2 +5% of the al powder, milling balls were added at a ball-to-ball ratio of 5. Drying at 70 deg.C, vacuum under vacuum degree of less than 10Pa and 200MPa, compression molding, maintaining for 10min, sintering at 1050 deg.C under argon protection and pressureless for 2 hr, cooling at 3 deg.C/min, and density of 97.83% T.D. The fluorine content in sample 4 was found to be 57.8% by calculation.
So far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. It is to be understood that the implementations not shown or described in the drawings or in the text of this specification are in a form known to those skilled in the art and are not described in detail. In addition, the above definitions of the components are not limited to the specific structures, shapes or modes mentioned in the embodiments, and those skilled in the art may easily modify or replace them.
It should also be noted that, unless otherwise indicated, the numerical parameters set forth in this specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. In particular, all numbers expressing dimensions, range conditions, and so forth, used in the specification and claims are to be understood as being modified in all instances by the term "about". In general, the meaning of the expression is meant to encompass variations of a specified number by ± 10% in some embodiments, by ± 5% in some embodiments, by ± 1% in some embodiments, by ± 0.5% in some embodiments.
It will be appreciated by a person skilled in the art that various combinations and/or combinations of features described in the various embodiments and/or claims of the present application are possible, even if such combinations or combinations are not explicitly described in the present application. In particular, various combinations and/or combinations of the features recited in the various embodiments and/or claims of the present application may be made without departing from the spirit and teachings of the present application. All such combinations and/or associations are intended to fall within the scope of this application.
The above-mentioned embodiments are further described in detail for the purpose of illustrating the invention, and it should be understood that the above-mentioned embodiments are only illustrative of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A magnesium fluoride composite ceramic comprising:
magnesium fluoride matrix, binder and sintering aid;
wherein, the magnesium fluoride matrix accounts for 80-95 wt% of the total content of the composite ceramic;
the addition amount of the binder is 0-1 wt% of the total content of the composite ceramic;
the addition amount of the sintering aid is 0 to 20 weight percent of the total content of the composite ceramic;
the sintering aid comprises at least one of lithium fluoride, calcium fluoride, aluminum fluoride and metallic aluminum.
2. The magnesium fluoride composite ceramic of claim 1,
the addition amount of the lithium fluoride is 0 to 10 weight percent of the total content of the composite ceramic;
the addition amount of the metallic aluminum is 0 to 10 weight percent of the total content of the composite ceramic.
3. The magnesium fluoride composite ceramic of claim 1,
the addition amount of the calcium fluoride is 0 to 10 weight percent of the total content of the composite ceramic;
the adding amount of the aluminum fluoride is 0 to 5 weight percent of the total content of the composite ceramic.
4. The magnesium fluoride composite ceramic of claim 1,
the binder is polyvinyl butyral ester or polyvinylpyrrolidone.
5. A method of making the magnesium fluoride composite ceramic of any one of claims 1 to 4, comprising:
mixing a magnesium fluoride matrix and a sintering aid, and adding the mixture into a mixer to obtain mixed powder;
drying the mixed powder until no agglomeration exists, and sieving to obtain uniform powder;
filling the uniform powder into a pressing die or an isostatic pressing die sleeve, and pressing and forming to obtain a green body;
and putting the pressed green body into a sintering furnace, and sintering to obtain a magnesium fluoride product.
6. The method of claim 5, wherein the mixing the magnesium fluoride matrix with the sintering aid into a blender further comprises: adding grinding balls according to a ball-material ratio of 3.
7. The method according to claim 5, wherein the drying temperature of the mixed powder is 60 ℃ to 75 ℃, the drying environment is vacuum, and the vacuum degree is lower than 10Pa.
8. The method of claim 5, wherein the press forming comprises:
a dynamic pressing process, wherein the pressure of a steel mould in the dynamic pressing process is 250 MPa-500 MPa, and the pressure is maintained for 10min-20min;
or
And (3) a static pressing process, wherein the isostatic pressure of the static pressing process is 50 MPa-200 MPa, and the pressure is maintained for 30min-40min.
9. The method of claim 5, wherein said placing the pressed green body into a sintering furnace comprises: the sintering temperature is 800-1100 ℃, the heat preservation time is 2-6 h, and the sintering atmosphere is argon.
10. The method of claim 5, wherein the pressed green body is placed into a sintering furnace, and further comprising a cooling process, wherein the cooling process is carried out at a uniform cooling speed of 1-5 ℃/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310002905.1A CN115872746A (en) | 2023-01-03 | 2023-01-03 | Magnesium fluoride composite ceramic and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310002905.1A CN115872746A (en) | 2023-01-03 | 2023-01-03 | Magnesium fluoride composite ceramic and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115872746A true CN115872746A (en) | 2023-03-31 |
Family
ID=85757911
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310002905.1A Pending CN115872746A (en) | 2023-01-03 | 2023-01-03 | Magnesium fluoride composite ceramic and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115872746A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000072554A (en) * | 1998-08-20 | 2000-03-07 | Taiheiyo Cement Corp | Fluoride ceramic sintered compact and its production |
| US20160002116A1 (en) * | 2013-07-08 | 2016-01-07 | University Of Tsukuba | Fluoride sintered body for neutron moderator and method for producing the same |
| US20160082282A1 (en) * | 2014-09-24 | 2016-03-24 | University Of Tsukuba | MgF2-CaF2 BINARY SYSTEM SINTERED BODY FOR RADIATION MODERATOR AND METHOD FOR PRODUCING THE SAME |
| CN111072387A (en) * | 2019-12-31 | 2020-04-28 | 中国建筑材料科学研究总院有限公司 | Aluminum fluoride composite ceramic and preparation method thereof |
| CN112831678A (en) * | 2020-12-29 | 2021-05-25 | 山东亚赛陶瓷科技有限公司 | Aluminum/aluminum fluoride composite ceramic neutron moderator and preparation method thereof |
-
2023
- 2023-01-03 CN CN202310002905.1A patent/CN115872746A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000072554A (en) * | 1998-08-20 | 2000-03-07 | Taiheiyo Cement Corp | Fluoride ceramic sintered compact and its production |
| US20160002116A1 (en) * | 2013-07-08 | 2016-01-07 | University Of Tsukuba | Fluoride sintered body for neutron moderator and method for producing the same |
| US20160082282A1 (en) * | 2014-09-24 | 2016-03-24 | University Of Tsukuba | MgF2-CaF2 BINARY SYSTEM SINTERED BODY FOR RADIATION MODERATOR AND METHOD FOR PRODUCING THE SAME |
| CN111072387A (en) * | 2019-12-31 | 2020-04-28 | 中国建筑材料科学研究总院有限公司 | Aluminum fluoride composite ceramic and preparation method thereof |
| CN112831678A (en) * | 2020-12-29 | 2021-05-25 | 山东亚赛陶瓷科技有限公司 | Aluminum/aluminum fluoride composite ceramic neutron moderator and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105506345B (en) | High heat-conductive diamond/copper composite encapsulating material and preparation method thereof | |
| CN110415845B (en) | High-uranium-density composite fuel pellet and preparation method thereof | |
| CN111593218B (en) | Micro-nano particle reinforced aluminum-based composite material and preparation method thereof | |
| CN104973865A (en) | Preparation method of high-thermal-conductivity aluminum nitride ceramic | |
| CN106756281B (en) | A kind of neutron absorber material of high rare-earth content and preparation method thereof | |
| CN111349805B (en) | High-temperature structure function integrated Mg (Al) B2And B4C-co-enhanced aluminum-based neutron absorption material and preparation method thereof | |
| CN113943159B (en) | Preparation method of boron carbide composite ceramic | |
| CN110273078A (en) | A kind of magnetism (FeCoNi1.5CuBmREn)P/ Al composite material and preparation method | |
| CN109014231B (en) | Preparation method of composite rare earth tungsten powder | |
| CN112831678B (en) | Aluminum/aluminum fluoride composite ceramic neutron moderator and preparation method thereof | |
| CN114315490A (en) | PTFE-Al-Ce energetic structural material and preparation method thereof | |
| CN108257880B (en) | Process method for preparing diamond/Si (Al) composite material by vacuum infiltration method | |
| CN109332717B (en) | Preparation method of spherical molybdenum titanium zirconium alloy powder | |
| CN115872746A (en) | Magnesium fluoride composite ceramic and preparation method thereof | |
| CN107841669B (en) | High-thermal-conductivity active composite packaging material and preparation method thereof | |
| CN103602868A (en) | Preparation method of high-density fine-grain W-TiC alloy material | |
| CN100335664C (en) | Shielded Pb-base composite materials with high-energy ray and production thereof | |
| CN115404386B (en) | High-entropy alloy material with high hardness and low neutron absorption cross section and preparation method thereof | |
| CN111072387A (en) | Aluminum fluoride composite ceramic and preparation method thereof | |
| CN111326265B (en) | Uranium dioxide-carbide composite fuel pellet and preparation method thereof | |
| TW201928081A (en) | Preparation method of high purity and densified tungsten-titanium metal | |
| CN114315492A (en) | PTFE-Al-La energetic structural material and preparation method thereof | |
| CN114426751A (en) | PTFE-Al-P energetic structural material and preparation method thereof | |
| CN104493169A (en) | Ceramic particle local reinforced metal heat sink and preparing method thereof | |
| US6635099B2 (en) | Aqueous nonferrous feedstock material for injection molding |
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 |