CN114657481B - Preparation method of rare earth composite material - Google Patents
Preparation method of rare earth composite material Download PDFInfo
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- CN114657481B CN114657481B CN202210219762.5A CN202210219762A CN114657481B CN 114657481 B CN114657481 B CN 114657481B CN 202210219762 A CN202210219762 A CN 202210219762A CN 114657481 B CN114657481 B CN 114657481B
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- rare earth
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
- C22C47/02—Pretreatment of the fibres or filaments
- C22C47/06—Pretreatment of the fibres or filaments by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element
- C22C47/062—Pretreatment of the fibres or filaments by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element from wires or filaments only
- C22C47/066—Weaving wires
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
- C22C47/08—Making alloys containing metallic or non-metallic fibres or filaments by contacting the fibres or filaments with molten metal, e.g. by infiltrating the fibres or filaments placed in a mould
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C49/00—Alloys containing metallic or non-metallic fibres or filaments
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/02—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working in inert or controlled atmosphere or vacuum
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
- C22F1/18—High-melting or refractory metals or alloys based thereon
Abstract
The invention discloses a preparation method of a rare earth composite material, wherein the chemical formula of the rare earth composite material is R-H-M, R-H exists in the form of rare earth hydride, rare earth R is selected from at least one of lanthanide elements and Y elements, and M is selected from at least one of W or Mo, and the preparation method comprises the following steps: weaving at least one of tungsten wires, molybdenum wires or tungsten-molybdenum alloy wires into an M woven body; stacking at least two layers of the M braided bodies, sintering, and cooling along with a furnace to obtain an M framework with the porosity of 10-40%; immersing the M framework into the R molten liquid for infiltration treatment, and separating the M framework subjected to infiltration treatment from the R molten liquid; and (3) cooling the M framework, and then performing heat treatment in a hydrogen atmosphere to obtain the rare earth composite material. The rare earth composite material has high energy release, can realize high-efficiency energy release in an oxygen-free environment, and obviously improves the application environment of the metal energy release material.
Description
Technical Field
The invention relates to a metal material, in particular to a preparation method of a rare earth composite material.
Background
In the currently known metal energy release material, the energy release mechanism is that elements which are easy to react with oxygen to release a large amount of heat; the second is a reaction between the metal and the metal or between the metal and an intermediate product. The existing metal energy release material mainly takes high-activity elements such as Zr, al and the like as main energy release elements, realizes the combustion effect in the environment with high air or oxygen content, but generally has poor energy release effect in the environments with low pressure and oxygen deficiency, underwater and the like, has insufficient mechanical properties, and is difficult to be used for structural parts. How to prepare an energy-releasing metal which can realize high-efficiency energy release in an oxygen-free environment, has strong energy release in a conventional environment, has certain mechanical property and can be stably stored for a long time is a problem to be solved urgently.
Disclosure of Invention
The invention provides a preparation method of a rare earth composite material, and the prepared rare earth composite material can realize high-efficiency energy release in an oxygen-free environment, is an energy-release metal composite material which has strong energy release in a conventional environment, has certain mechanical property and can be stably stored for a long time.
In order to achieve the purpose, the invention adopts the technical scheme that:
a method of making a rare earth composite material having the formula R-H-M, wherein R-H is present as a rare earth hydride, the rare earth R is selected from at least one of Nd, pr, dy, tb, ho, la, ce, pm, sm, eu, gd, er, tm, yb, lu and Y elements, and the M is selected from at least one of W or Mo, the method comprising the steps of:
a. weaving at least one of tungsten wires, molybdenum wires or tungsten-molybdenum alloy wires into an M woven body;
b. stacking at least two layers of the M braided bodies, then placing the M braided bodies into a vacuum atmosphere furnace for sintering, and cooling along with the furnace to obtain an M framework, wherein the porosity of the M framework is 10% -40%;
c. immersing the M framework into the R molten liquid for infiltration treatment, and separating the M framework subjected to infiltration treatment from the R molten liquid;
d. and c, cooling the M framework obtained in the step c, and then performing heat treatment in a hydrogen atmosphere to obtain the rare earth composite material.
Preferably, the components of the rare earth composite material comprise 3-21 wt% of R-H, and the balance of M.
Preferably, the components of the rare earth composite material comprise 5-15 wt% of R-H, and the balance of M.
Preferably, R is at least one selected from Nd, pr, ho, dy, tb, Y and Gd.
Preferably, M includes at least W.
Preferably, the diameter of the tungsten wire, the molybdenum wire or the tungsten-molybdenum alloy wire is 10-100.0 μm.
Preferably, in step a, the tungsten wire, the molybdenum wire or the tungsten-molybdenum alloy wire is subjected to acid pickling treatment.
Preferably, in the step b, sintering is carried out in a positive pressure hydrogen or argon atmosphere, the sintering temperature is 1400-2200 ℃, and the sintering time is 4-8 h.
Preferably, in the step c, the temperature of the infiltration treatment is 100-150 ℃ higher than the melting point of the rare earth R, and the time of the infiltration treatment is 0.5-4 h.
Preferably, in the step d, the M framework obtained in the step c is cooled and then placed into a vacuum atmosphere furnace, hydrogen is filled into the furnace, the temperature is raised to 100-350 ℃, and heat treatment is carried out.
The beneficial effects of the invention are:
1. the rare earth composite material prepared by the invention exists in a form of pseudo alloy, not only can realize better energy release effect in an aerobic environment, but also has certain mechanical property, and has better energy release effect in low-oxygen environments such as carbon dioxide, nitrogen, water and the like.
2. The method of the invention carries out heat treatment on the sintered rare earth composite material in hydrogen atmosphere, so that the rare earth composite material can be stored in the air for a long time, and the composite material can generate the effect of blasting when releasing energy in an aerobic environment.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention clearer and more obvious, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In a preferred embodiment, the composition of the rare earth composite includes 3wt% to 21wt% of R-H, with the balance being M.
Preferably, the components of the rare earth composite material comprise 5-15 wt% of R-H, and the balance of M.
In a preferred embodiment, R is at least one element selected from Nd, pr, ho, dy, tb, Y and Gd.
Preferably, R is at least one element selected from Nd, pr, ho, dy and Tb.
In a preferred embodiment, M comprises W and Mo, and the W content is 4 to 9 times the Mo content.
In a preferred embodiment, M is preferably W.
In a preferred embodiment, the tungsten wire, molybdenum wire or tungsten-molybdenum alloy wire has a diameter of 10 μm to 100 μm.
In a preferred embodiment, the tungsten wire, molybdenum wire or tungsten-molybdenum alloy wire is acid-washed.
In a recommended embodiment, in the step b, sintering is carried out in a positive pressure hydrogen or argon atmosphere, the sintering temperature is 1400-2200 ℃, and the sintering time is 4-8 h.
In a preferred embodiment, the temperature of the infiltration treatment is 100 to 150 ℃ higher than the melting point of the rare earth R, and the time of the infiltration treatment is 0.5 to 4 hours.
In the infiltration treatment process, the low-melting-point rare earth element is melted and infiltrated into the tungsten and/or molybdenum skeleton, and the rare earth element exists in the gap of the tungsten and/or molybdenum skeleton to form a pseudo alloy.
In a recommended embodiment, the M framework obtained in the step c is cooled and then placed into a vacuum atmosphere furnace, hydrogen is filled into the furnace, the temperature is raised to 100-350 ℃, and heat treatment is carried out.
The sintered rare earth composite material is subjected to heat treatment in a hydrogen atmosphere, so that the composite material can be stored in the air for a long time, and the composite material can generate an explosion effect when releasing energy in an aerobic environment.
In a preferred embodiment, the surface of the composite material may be subjected to a surface protection treatment, such as painting, surface passivation, etc., as required, for the purpose of further prolonging the storage period.
The present invention will be described in further detail with reference to examples.
Example one
The preparation method of the rare earth composite material of the embodiment comprises the following steps:
pre-processing: soaking a tungsten wire, a molybdenum wire or a tungsten-molybdenum alloy wire with the diameter of 10 mu m in 1mol/L hydrochloric acid, washing with water, and drying to remove impurities on the surface of the tungsten wire, the molybdenum wire or the tungsten-molybdenum alloy wire;
weaving and forming: weaving tungsten wires, molybdenum wires or tungsten-molybdenum alloy wires into the M braid according to the porosity parameters of the M braid of each example and comparative example in Table 1;
sintering treatment: stacking four layers of the M braided body, placing the M braided body into a vacuum atmosphere furnace, filling hydrogen into the furnace, heating to 2100 ℃, sintering for 10 hours, and cooling along with the furnace to obtain an M framework with porosity, which is described in each example and comparative example in the table 1;
and (3) dissolving and permeating treatment: the M framework is immersed into the melt of the rare earth of each embodiment and comparative example, the infiltration treatment is carried out, the temperature of the infiltration treatment is 150 ℃ higher than the melting point of the rare earth, the time of the infiltration treatment is 3h, after the infiltration treatment, the temperature is reduced to be 10 ℃ higher than the melting point of the rare earth, and the M framework after the infiltration treatment is separated from the melt of the rare earth.
And (3) heat treatment: and cooling the M framework after infiltration treatment, putting the M framework into a vacuum furnace, filling hydrogen into the furnace, heating to 180 ℃, and carrying out heat treatment to obtain the rare earth composite material.
The composition of the rare earth composite materials prepared in each example and each comparative example was measured, and the results are shown in table 1.
TABLE 1 porosity (%) of each example and each comparative example and composition (wt%) of the obtained rare earth composite material
And (3) performing static compression strength detection and dynamic compression detection on the rare earth composite materials prepared in the embodiments and the respective proportions, evaluating the mechanical properties of the rare earth composite materials, and representing the energy released in an oxygen environment by using the reaction heat delta H.
TABLE 2 evaluation of the properties of the examples and comparative rare earth composites
To conclude, we can conclude that:
when the M framework components are the same and the porosity is more than or equal to 10% and less than or equal to 40%, the R-H mass fraction of the finally prepared rare earth composite material is increased along with the increase of the porosity, the reaction heat is increased, a good energy release effect can be realized in an aerobic environment, certain mechanical properties are realized, and the good energy release effect is realized in low-oxygen environments such as carbon dioxide, nitrogen, water and the like.
When the porosity of the M framework is lower than 10%, the R-H mass fraction of the finally prepared rare earth composite material is lower than 3wt%, and the reaction heat is too low to meet the application requirement of the energetic material; when the porosity of the M framework is higher than 50%, the contact points between the tungsten filaments are too few, the solid-phase sintering effect is poor, and although the finally prepared rare earth composite material has a good energy-containing effect, the mechanical strength is too low to meet the application requirements of the energy-containing material.
Example two
The preparation method of the rare earth and tungsten composite material comprises the following steps:
pre-processing: soaking a tungsten wire with the diameter of 20 mu m in 1mol/L hydrochloric acid, washing with water, and drying to remove impurities on the surface of the tungsten wire;
weaving and forming: weaving tungsten filaments into a tungsten filament woven body according to the porosity parameters of the tungsten filament woven bodies of the examples and the comparative examples in the table 3;
sintering treatment: stacking four layers of the tungsten filament braided bodies, placing the tungsten filament braided bodies into a vacuum atmosphere furnace for sintering, filling hydrogen into the furnace, heating to 2100 ℃, sintering for 10 hours, and cooling along with the furnace to obtain the tungsten framework with porosity of each embodiment and comparative example in the table 3;
and (3) dissolving and permeating treatment: the tungsten skeleton is immersed into the melting liquid of the rare earth of each embodiment and comparative example, the infiltration treatment is carried out, the temperature of the infiltration treatment is 100 ℃ higher than the melting point of the rare earth, the time of the infiltration treatment is 4 hours, after the infiltration treatment, the temperature is reduced to 20 ℃ higher than the melting point of the rare earth, and the tungsten skeleton after the infiltration treatment is separated from the melting liquid of the rare earth.
And (3) heat treatment: and cooling the tungsten framework after infiltration treatment, putting the tungsten framework into a vacuum furnace, filling hydrogen into the furnace, heating to 250 ℃, and carrying out heat treatment to obtain the rare earth and tungsten composite material.
The compositions of the rare earth and tungsten composites prepared in the examples and comparative examples were measured, and the results are shown in Table 3.
TABLE 3 porosity (%) of each example and each comparative example and composition (wt%) of the obtained rare earth composite material
And (3) performing static compressive strength detection and dynamic compressive strength detection on the rare earth and tungsten composite materials in each embodiment and each proportion, evaluating the mechanical properties of the rare earth and tungsten composite materials, and evaluating the energy released by combustion of the rare earth and tungsten composite materials in an oxygen environment by using the reaction heat delta H. The evaluation results of the examples and comparative rare earth-tungsten composites are shown in table 4:
TABLE 4 evaluation of the properties of the examples and comparative rare earth-tungsten composites
To conclude, we can conclude that:
when the porosity of the tungsten skeleton is more than or equal to 10% and less than or equal to 40%, the R-H mass fraction of the finally prepared rare earth and tungsten composite material is increased along with the increase of the porosity, the reaction heat is increased, a good energy release effect can be realized in an aerobic environment, certain mechanical properties are realized, and the good energy release effect is realized in low-oxygen environments such as carbon dioxide, nitrogen, water and the like.
When the porosity of the M framework is lower than 10%, the R-H mass fraction of the finally prepared rare earth composite material is lower than 3wt%, and the reaction heat is too low to meet the application requirement of the energetic material; when the porosity of the M framework is higher than 50%, the contact points between the tungsten filaments are too few, the solid-phase sintering effect is poor, and although the finally prepared rare earth composite material has a good energy-containing effect, the mechanical strength is too low to meet the application requirements of the energy-containing material.
While the foregoing specification illustrates and describes the preferred embodiments of the present invention, it is to be understood that the invention is not limited to the precise forms disclosed herein and is not to be interpreted as excluding the existence of additional embodiments that are also intended to be encompassed by the present invention as modified within the spirit and scope of the invention as described herein. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. The preparation method of the rare earth composite material is characterized in that the chemical formula of the rare earth composite material is R-H-M, wherein R-H exists in the form of rare earth hydride, the components of the rare earth composite material comprise 3-21 wt% of R-H by mass fraction and the balance of M, the rare earth R is selected from at least one of Nd, pr, dy, tb, ho, la, ce, sm, eu, gd, er, tm, yb, lu and Y, and the M is selected from at least one of W or Mo, and the preparation method comprises the following steps:
a. weaving at least one of tungsten wires, molybdenum wires or tungsten-molybdenum alloy wires into an M woven body;
b. stacking at least two layers of the M braided body, placing the M braided body into a vacuum atmosphere furnace, sintering in positive pressure hydrogen or argon atmosphere at the sintering temperature of 1400-2200 ℃ for 4-8 h, and cooling along with the furnace to obtain an M framework, wherein the porosity of the M framework is 10-40%;
c. immersing the M framework into the R molten liquid for infiltration treatment, wherein the temperature of the infiltration treatment is 100-150 ℃ higher than the melting point of the rare earth R, the infiltration treatment time is 0.5-4 h, and separating the M framework after the infiltration treatment from the R molten liquid;
d. and c, cooling the M framework obtained in the step c, putting the M framework into a vacuum atmosphere furnace, filling hydrogen into the furnace, heating to 100-350 ℃, and carrying out heat treatment to obtain the rare earth composite material.
2. The preparation method according to claim 1, wherein the components of the rare earth composite material comprise 5-15 wt% of R-H by mass fraction, and the balance is M.
3. The method according to claim 1, wherein R is at least one element selected from Nd, pr, ho, dy, tb, Y and Gd.
4. The method of claim 1, wherein M comprises at least W.
5. The production method according to claim 1, wherein the tungsten wire, molybdenum wire, or tungsten-molybdenum alloy wire has a diameter of 10 μm to 100 μm.
6. The method according to claim 1, wherein in step a, the tungsten wire, molybdenum wire, or tungsten-molybdenum alloy wire is subjected to acid pickling.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| GB836749A (en) * | 1957-07-17 | 1960-06-09 | Siemens Ag | Improvements in or relating to the production of composite metal |
| US4235630A (en) * | 1978-09-05 | 1980-11-25 | Caterpillar Tractor Co. | Wear-resistant molybdenum-iron boride alloy and method of making same |
| US20030217828A1 (en) * | 2002-05-22 | 2003-11-27 | Mark Opoku-Adusei | Metal matrix composite having improved microstructure and the process for making the same |
| JP3809435B2 (en) * | 2002-11-11 | 2006-08-16 | 住友電気工業株式会社 | Electrode material for EDM |
| JP2006144064A (en) * | 2004-11-18 | 2006-06-08 | Neomax Co Ltd | Method for cleaning holder for sintering rare-earth sintering magnet, and method for manufacturing rare-earth sintering magnet |
| EP2511920B1 (en) * | 2009-12-09 | 2016-04-27 | Aichi Steel Corporation | Process for production of rare earth anisotropic magnet |
| CN102061431B (en) * | 2010-12-17 | 2013-04-03 | 上海工程技术大学 | Tungsten-copper composite material and preparation method thereof |
| US9212409B2 (en) * | 2012-01-18 | 2015-12-15 | Cook Medical Technologies Llc | Mixture of powders for preparing a sintered nickel-titanium-rare earth metal (Ni-Ti-RE) alloy |
| CN103866171A (en) * | 2012-12-17 | 2014-06-18 | 北矿新材科技有限公司 | Sintering method of rare earth tungsten electrode blank strip |
| CN103194629B (en) * | 2013-03-26 | 2015-06-10 | 金堆城钼业股份有限公司 | Method for preparing tungsten molybdenum copper composite material |
| CN103740994B (en) * | 2014-02-10 | 2015-09-02 | 中国科学院合肥物质科学研究院 | Nanostructure tungsten alloy and preparation method thereof |
| WO2015121915A1 (en) * | 2014-02-12 | 2015-08-20 | 日東電工株式会社 | Rare earth permanent magnet and production method for rare earth permanent magnet |
| CN110520961B (en) * | 2017-03-31 | 2022-01-25 | 联合材料公司 | Tungsten electrode material |
| CN107794399B (en) * | 2017-10-13 | 2022-03-15 | 浙江福达合金材料科技有限公司 | Preparation method of superfine high-dispersion silver-tungsten electrical contact material |
| CN112251622B (en) * | 2020-09-17 | 2022-03-18 | 洛阳科威钨钼有限公司 | Production method of stirrer for rare earth doped smelting metal |
| CN113634761A (en) * | 2021-08-16 | 2021-11-12 | 合肥工业大学 | Preparation method of rare earth oxide reinforced tungsten-copper-based composite material |
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