CN113185294A - Preparation method of ZrC powder with controllable macro-particle size - Google Patents

Preparation method of ZrC powder with controllable macro-particle size Download PDF

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CN113185294A
CN113185294A CN202110563856.XA CN202110563856A CN113185294A CN 113185294 A CN113185294 A CN 113185294A CN 202110563856 A CN202110563856 A CN 202110563856A CN 113185294 A CN113185294 A CN 113185294A
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particle size
zrc powder
powder
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reaction
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喇培清
许珂
占发琦
张华�
吴浩恺
朱敏
郑月红
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Lanzhou University of Technology
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/56—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides
    • C04B35/5607—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on refractory metal carbides
    • C04B35/5622—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on refractory metal carbides based on zirconium or hafnium carbides
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    • C01B32/90—Carbides
    • 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
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    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/01—Particle morphology depicted by an image
    • C01P2004/03—Particle morphology depicted by an image obtained by SEM
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/30—Particle morphology extending in three dimensions
    • C01P2004/32—Spheres
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer

Abstract

A preparation method of ZrC powder with controllable macro-particle size comprises the following steps: weighing reaction materials according to a preset proportion, and adding an inert diluent with a preset content to prepare an initial mixture; step (2) placing the initial mixture into a ball mill for uniform mixing, and then pressing the mixture into a cake-shaped blank with the diameter of 80 mm and the height of about 20-50 mm on a press machine; putting the cake-shaped blank into a reaction kettle, putting an ignition agent on the blank, filling protective gas for gas washing, then filling the protective gas for pressure maintaining, and continuously heating until the system generates a self-propagating reaction to obtain a black blocky initial product; and (4) crushing the primary product, leaching with a hydrochloric acid solution and distilled water, and drying in a vacuum drying oven to obtain ZrC powder after the purification standard is reached.

Description

Preparation method of ZrC powder with controllable macro-particle size
Technical Field
The invention relates to a large-scale preparation technology of ZrC powder with controllable granularity.
Background
ZrC is an ultra-high temperature ceramic material with great prospect, has extremely high melting point and hardness and excellent high temperature performance, and plays an increasingly important role in the fields of aerospace, national defense science and technology, chemical industry, high-end equipment manufacturing industry and the like. However, the ZrC powder has the problem of poor sintering performance, and the sintering performance of the powder is mainly limited by the problems of low purity, uneven granularity and the like.
It is worth noting that different preparation processes can have significant influence on some properties (such as particle size, purity, chemical activity, etc.) of the ZrC powder, and further influence the practical application properties of the material. This means that more excellent and advanced production processes are required, and the powder prepared by the preparation process commonly used at present hardly meets the standards of particle size, purity and preparation scale. The problems of over high oxygen content, low purity, uneven particle size distribution, serious particle agglomeration, poor sintering performance and the like exist in the ZrC powder prepared at present.
Disclosure of Invention
The invention aims to provide a preparation method of ZrC powder with controllable macro-particle size.
The invention relates to a preparation method of a ZrC powder with controllable macro-particle size, which comprises the following steps:
weighing reaction materials according to a preset proportion, and adding an inert diluent with a preset content to prepare an initial mixture;
step (2) placing the initial mixture into a ball mill for uniform mixing, and then pressing the mixture into a cake-shaped blank with the diameter of 80 mm and the height of about 20-50 mm on a press machine;
putting the cake-shaped blank into a reaction kettle, putting an ignition agent on the blank, filling protective gas for gas washing, then filling the protective gas for pressure maintaining, and continuously heating until the system generates a self-propagating reaction to obtain a black blocky initial product;
and (4) crushing the primary product, leaching with a hydrochloric acid solution and distilled water, and drying in a vacuum drying oven to obtain ZrC powder after the purification standard is reached.
The invention has the beneficial effects that: the energy consumption cost is low, an external heat source is not needed after the reaction is started, and the reaction is only needed to be heated to 280-350 ℃; the process flow is simple, the production equipment is simplified, and the operation is simple; the yield is high, the preparation period is short, high-purity ZrC powder with controllable granularity can be prepared in a macroscopic quantity (kilogram level) at one time, the morphology of the product is regular spheroidal, and the granularity is fine and uniform; the particle size of the product can be regulated and controlled to be reduced from about 1 mu m to about 30-50 nm by changing the content of sodium chloride.
Drawings
Fig. 1 is an XRD pattern of the prepared sample, fig. 2 is an EDS pattern of the prepared sample, fig. 3 is an SEM image of the prepared sample, fig. 4 is a particle size distribution diagram of the sample (0 wt.% diluent), and fig. 5 is a particle size distribution diagram of the sample (30 wt.% NaCl — KCl).
Detailed Description
The invention relates to a preparation method of a ZrC powder with controllable macro-particle size, which comprises the following steps:
weighing reaction materials according to a preset proportion, and adding an inert diluent with a preset content to prepare an initial mixture;
step (2) placing the initial mixture into a ball mill for uniform mixing, and then pressing the mixture into a cake-shaped blank with the diameter of 80 mm and the height of about 20-50 mm on a press machine;
putting the cake-shaped blank into a reaction kettle, putting an ignition agent on the blank, filling protective gas for gas washing, then filling the protective gas for pressure maintaining, and continuously heating until the system generates a self-propagating reaction to obtain a black blocky initial product;
and (4) crushing the primary product, leaching with a hydrochloric acid solution and distilled water, and drying in a vacuum drying oven to obtain ZrC powder after the purification standard is reached.
In the preparation method, the reaction materials in the step (1) and the mass ratio thereof are zirconia: graphite: magnesium powder = 123:12: 61; inert diluent species include NaCl, MgCl2KCl or a mixture thereof; the amount of diluent added is 0 wt.% of the total mass of the reaction mass~30 wt.%。
According to the preparation method, the ball milling parameters in the step (2) are that the time is 8-15 h, the rotating speed is 150 r/min, and the ball-to-material ratio is 2: 1; the pressure of the press is 30-50 MPa.
According to the preparation method, the preheating temperature in the step (3) is 280-350 ℃; the protective atmosphere is argon, and the pressure maintaining pressure is 2-4 MPa.
The preparation method described above, wherein the hydrochloric acid solution in step (4) is 3 mol/L hydrochloric acid diluent and is in excess of 50 vol.%; the purification standard is as follows: in the pickling process, the color of the pH test paper tested by the pickling waste liquid twice is not changed; in the water washing process, the water washing waste liquid is titrated by a silver nitrate solution, so that no white precipitate is generated; drying at 70 deg.C for 12 h.
According to the preparation method, the average particle size of the ZrC powder is regulated and controlled within the range of 510-30 nm.
The following are specific examples of the present invention, and the technical solutions of the present invention will be further described with reference to the examples, but the present invention is not limited to the examples.
Example 1:
the reactant materials in this example were zirconia (> 99.5 wt.%, 1 μm), graphite (99.95 wt.%), magnesium powder (> 99.5 wt.%, 325 mesh). NaCl is selected as a diluent, the addition amount is 0 wt.%, the ball milling time is 8 h, the pressurizing pressure is 30 MPa, and the pressure of the protective atmosphere is 2 MPa, and the method specifically comprises the following steps:
(1) firstly, respectively placing zirconium oxide, graphite and a diluent in a drying oven for drying, adjusting the temperature to 50 ℃ for 24 hours, then batching the zirconium oxide, the graphite and the magnesium powder according to the weight ratio of 123:12:61, wherein the addition amount of NaCl accounts for 0 wt% of the total mass of the reaction materials, and the total mass of the initial mixture is 1 kg. Accurately weighing the reaction raw materials by using an electronic balance;
(2) mixing the initial mixture with QM-ISP4 planetary ball mill at 150 r/min for 8 hr, at a ball-to-material ratio of 2: 1;
(3) pressing the uniformly mixed reaction materials into a cake-shaped blank with the diameter of 80 mm and the height of about 20-50 mm in a die on a Y32-100t hydraulic press under the pressure of 30 MPa;
(4) putting the cake-shaped blank into a combustion synthesis reaction kettle, filling 0.5 MPa of argon, keeping for 10-20 min, discharging gas, and removing air in the kettle; when the temperature in the reaction kettle is heated to 170 ℃, discharging residual gas in the kettle, then filling argon until the pressure in the kettle is 2 Mpa, and when the temperature in the kettle is raised to 308 ℃, carrying out self-propagating reaction; and after the sample is naturally cooled in the reaction kettle, taking out the black block sample, crushing the black block sample and then carrying out subsequent purification.
(5) A50 vol.% excess of a 3 mol/L dilution of hydrochloric acid was made with 12 mol/L standard hydrochloric acid, and the product powder was immersed in it and placed in a magnetic stirrer for continuous stirring. And in the pickling process, pH test paper is used for testing the pH value of the solution every 4 hours or so to ensure that the solution keeps acidic, and if the solution is neutral or alkaline, a proper amount of hydrochloric acid diluent is required to be added again. And finishing the acid washing when the color of the pH test paper tested twice is not changed any more. Then repeatedly washing with distilled water to remove excessive salt, wherein the standard of washing is that the solution after the last washing is dripped into silver nitrate detection solution to avoid white precipitate, and Cl in the water washing solution is detected-To ensure that the salt is sufficiently removed. Finally, the isolated product was placed in a vacuum oven and dried at 70 ℃ for 12 h.
Example 2:
the reactant materials in this example were zirconia (> 99.5 wt.%, 1 μm), graphite (99.95 wt.%), magnesium powder (> 99.5 wt.%, 325 mesh). NaCl is selected as a diluent, the adding amount is 10 wt.%, the ball milling time is 8 h, the pressurizing pressure is 30 MPa, and the pressure of the protective atmosphere is 2 MPa, and the specific steps are the same as those in example 1.
Example 3:
the reactant materials in this example were zirconia (> 99.5 wt.%, 1 μm), graphite (99.95 wt.%), magnesium powder (> 99.5 wt.%, 325 mesh). NaCl is selected as a diluent, the adding amount is 30 wt.%, the ball milling time is 8 h, the pressurizing pressure is 30 MPa, and the pressure of the protective atmosphere is 2 MPa, and the specific steps are the same as those in example 1.
Example 4:
in the embodiment, NaCl-KCl mixed salt is used as a diluent, the addition amount is 30 wt.%, the ball milling time is 8 h, the pressurizing pressure is 30 MPa, and the pressure of the protective atmosphere is 2 MPa, and the specific steps are the same as those in embodiment 1.
The sample prepared according to the invention as shown in FIG. 1 is pure phase ZrC. As shown in table 1, the purity of the ZrC powder was 95 wt.% or more. As shown in FIG. 3, the ZrC powder prepared by the method has a spherical-like particle shape and fine and uniform particles. As shown in Table 2, the ZrC powder prepared by changing the content of the diluent has an average particle diameter of 510-47 nm and a median diameter D50 of 576-46 nm.
TABLE 1 elemental content of inventive samples
Figure DEST_PATH_IMAGE001
TABLE 2 particle size parameters of samples prepared according to the invention
Figure DEST_PATH_IMAGE002
。

Claims (6)

1. A preparation method of ZrC powder with controllable macro-particle size is characterized by comprising the following steps:
weighing reaction materials according to a preset proportion, and adding an inert diluent with a preset content to prepare an initial mixture;
step (2) placing the initial mixture into a ball mill for uniform mixing, and then pressing the mixture into a cake-shaped blank with the diameter of 80 mm and the height of about 20-50 mm on a press machine;
putting the cake-shaped blank into a reaction kettle, putting an ignition agent on the blank, filling protective gas for gas washing, then filling the protective gas for pressure maintaining, and continuously heating until the system generates a self-propagating reaction to obtain a black blocky initial product;
and (4) crushing the primary product, leaching with a hydrochloric acid solution and distilled water, and drying in a vacuum drying oven to obtain ZrC powder after the purification standard is reached.
2. The method for preparing ZrC powder with controllable macro particle size as claimed in claim 1, wherein the method comprisesThe reaction materials in the step (1) and the mass ratio thereof are zirconia: graphite: magnesium powder = 123:12: 61; inert diluent species include NaCl, MgCl2KCl or a mixture thereof; the addition amount of the diluent accounts for 0-30 wt% of the total mass of the reaction materials.
3. The preparation method of the ZrC powder with controllable macro-particle size as claimed in claim 1, wherein the ball milling parameters in the step (2) are 8-15 h, the rotation speed is 150 r/min, and the ball-to-material ratio is 2: 1; the pressure of the press is 30-50 MPa.
4. The method for preparing the ZrC powder with controllable macro particle size as claimed in the claim, wherein the preheating temperature in the step (3) is 280-350 ℃; the protective atmosphere is argon, and the pressure maintaining pressure is 2-4 MPa.
5. The method for preparing the ZrC powder with the controllable macro-particle size as claimed in claim 1, wherein the hydrochloric acid solution in the step (4) is 3 mol/L hydrochloric acid diluent, and the hydrochloric acid solution is in 50 vol.% excess; the purification standard is as follows: in the pickling process, the color of the pH test paper tested by the pickling waste liquid twice is not changed; in the water washing process, the water washing waste liquid is titrated by a silver nitrate solution, so that no white precipitate is generated; drying at 70 deg.C for 12 h.
6. The method for preparing ZrC powder with controllable macro particle size as claimed in claim 1, wherein the average particle size of the ZrC powder is controlled within a range of 510-30 nm.
CN202110563856.XA 2021-05-24 2021-05-24 Preparation method of ZrC powder with controllable macro-particle size Pending CN113185294A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114804112A (en) * 2022-05-05 2022-07-29 兰州理工大学 Preparation method of nanoscale SiC powder with controllable macro-particle size

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WO2010085006A1 (en) * 2009-01-20 2010-07-29 The Industry & Academic Cooperation In Chungnam National University (Iac) Fabrication method of nano-sized metal carbide powder using self-propagating high-temperature synthesis
CN102344149A (en) * 2011-06-16 2012-02-08 兰州理工大学 Preparation method of ZrB2 powder material
CN103482626A (en) * 2013-09-12 2014-01-01 武汉科技大学 Zirconium carbide-silicon carbide composite powder and preparation method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101357762A (en) * 2008-09-09 2009-02-04 武汉理工大学 Method for zirconium carbide powder reduction synthesis by magnesium thermal combustion
WO2010085006A1 (en) * 2009-01-20 2010-07-29 The Industry & Academic Cooperation In Chungnam National University (Iac) Fabrication method of nano-sized metal carbide powder using self-propagating high-temperature synthesis
CN102344149A (en) * 2011-06-16 2012-02-08 兰州理工大学 Preparation method of ZrB2 powder material
CN103482626A (en) * 2013-09-12 2014-01-01 武汉科技大学 Zirconium carbide-silicon carbide composite powder and preparation method thereof

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114804112A (en) * 2022-05-05 2022-07-29 兰州理工大学 Preparation method of nanoscale SiC powder with controllable macro-particle size

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