CN1202044C - Method for preparing composite powder of ceramics with bionics structure - Google Patents
Method for preparing composite powder of ceramics with bionics structure Download PDFInfo
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- CN1202044C CN1202044C CN 03129396 CN03129396A CN1202044C CN 1202044 C CN1202044 C CN 1202044C CN 03129396 CN03129396 CN 03129396 CN 03129396 A CN03129396 A CN 03129396A CN 1202044 C CN1202044 C CN 1202044C
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Abstract
The present invention relates to a method for preparing a composite ceramic powder body with a bionic structure, which belongs to the field of ceramic materials. The present invention comprises: firstly, the structure and the material of composite ceramic powder with a bionic structure are determined; then the agglomeration powder body of a center material of the ceramic powder with a bionic structure is prepared to be treated with a heat treatment technology; the center material is mixed with a coating material, the mixture is treated with mechanochemistry surface modification by ball milling in order to realize the bionic sea anemone structure of the composite ceramic powder body; finally, the powder body which is prepared by ball milling is sphericized and densified by a plasma body, the composite ceramic powder body with a bionic structure is prepared. The composite ceramic powder body with a bionic sea anemone structure, which is obtained by the present invention, can be directly applied to hot spraying coating layers, laser cladding layers and sintering bodies which have high toughness, good high-temperature performance, high thermal shock resistance and high abrasive resistance. Thereby, the present invention has great market application prospect.
Description
Technical field
That the present invention relates to is a kind of preparation method of composite granule, and particularly a kind of preparation method who is used for the biomimetic features ceramic composite powder of thermospray, laser melting coating and sinter molding belongs to the stupalith field.
Background technology
The surface strengthening pottery and the compound coating thereof of various characteristicses such as thermospray deposits traditional micron order pottery on metallic matrix and composite ceramic material is wear-resisting to prepare, anti-corrosion, high temperature resistant, anti-oxidant, heat insulation, insulation, heat resistanceheat resistant radiation, superconduction and biological function, thereby in fields such as aerospace, the energy, electronics, automobile, machinofacture, medical science, obtain using very widely, and higher economy, society and safety benefit have been produced.The thermal Sperayed Ceramic Coatings of preparation usually causes the inefficacy of component at present, one of them major cause is the intrinsic fragility of stupalith, make that the toughness of ceramic coating, anti-machinery and thermal shock resistance properties are poor, this is the reason of essence the most that causes stupalith to lose efficacy.And the used for hot spraying powder is the key element of decision ceramic coating performance.Because traditional micron order ceramic powder particle is because the heat transfer rate height, and most of particle is in complete melted state when spraying or cladding, to increase content height, porosity height, unrelieved stress big for metastable phase in the coating, so the intensity and the poor toughness of coating inside, easily cause ceramic coating easily to peel off and ftracture, thereby cause coating to lose efficacy, seriously influenced its application under the special operation condition condition.In order to prepare the high-quality powder that can improve coating, many people have carried out many-sided research to this, and the research of novel powder is mainly reflected in the preparation of nano-powder and uses.
Find by literature search, Chinese patent application number: 02113978.3, title: the production method and methods for using them of large particle ball nano ceramic powder, this patent relates to large particle ball nano ceramic powder and technology, its material that relates to comprises that its production process is by the large granular spherical ceramic powder of the elementary ceramic powder preparation of nano-grade size: (1) utilizes wet ball grinding to obtain the water nano colloid; (2), obtain large particle ball nano ceramic powder with water nano colloid spraying drying; (3) spray-dried powders is heat-treated; (4) powder after the thermal treatment is carried out the plasma body densificationization.That but this patent only relates to is the preparation method of reunion powder, and our experiments show that, receive last powder and significantly grow up by pure by nano particle in the coating of thermospray or laser melting coating preparation, and the porosity height, its performance does not get a desired effect.
Summary of the invention
The present invention is directed to deficiency of the prior art and defective, a kind of preparation method of biomimetic features ceramic composite powder is provided, make resulting bionical (sea anemone) structural ceramics composite granule can directly apply to thermospray, laser melting coating and sintering, and thermally sprayed coating, laser cladding layer and the sintered compact of preparation have high obdurability and high high-temperature behavior, good thermal shock resistance, wear resistance.
The present invention is achieved through the following technical solutions, the present invention at first determines the structure and material of biomimetic features ceramic composite powder, to prepare biomimetic features ceramics powder body-centered portion material (reunion powder) then handles through thermal treatment process, again heart portion material and external cladding material are mixed by weight percentage, carry out the mechanochemistry surface modification by ball-milling technology, realize bionical (sea anemone) structure of ceramic composite powder, to pass through plasma body sphereization and densification by the powder of ball milling preparation at last, finish the preparation of biomimetic features ceramic composite powder.
Below preparation method of the present invention is further described, particular content is as follows:
(1) determines the structure and material of biomimetic features ceramic composite powder
● determine the structure of biomimetic features ceramic composite powder
Strengthening and toughening mechanism of and constructional feature thereof according to the natural biological sea anemone; in order to realize the local melting of powder in thermal spray process and the laser cladding process; reduce the generation and the unrelieved stress of the metastable phase in the coating; improve the intensity and the toughness of coating; bionical (sea anemone) structural ceramics composite granule is designed to the cappelletti packet mode structure of class sea anemone biology; its heart portion is the agglomerating particles or the sintered particles of dystectic relatively pottery or Composite Preparation, outer low-melting relatively pottery or the self-adhesive metal composite powder of coating.
● determine the material of biomimetic features ceramic composite powder
Constructional feature according to thermospray jet characteristics and bionical (sea anemone) structural ceramics composite granule, when careful portion material mainly was grouped into by one or more one-tenth in the stable zirconium white of aluminum oxide, yttrium oxide or strontium oxide, silicon carbide, the silicon nitride, the outer material that coats was submicron or nano aluminium oxide, titanium oxide or metal composite (Ni/Al, NiCrAl, NiCrAlY, Co's etc. is a kind of); When taking care portion's material and be a kind of in cobalt coated tungsten carbide or the nickel chromium triangle chromium carbide, outside coating material is a kind of among Co, the Ni/Al of ultra-fine level.
(2) will prepare biomimetic features ceramics powder body-centered portion reunion powder handles through thermal treatment process
Handle by thermal treatment process, remove the organic composition and the remaining moisture such as dispersion agent, binding agent, defoamer of reunion powder inside, realize combining closely of reunion powder inside, and keep the yardstick and the shape of its primary particle.Used Equipment for Heating Processing is selected well formula, chamber type electric resistance furnace or sintering oven for use.According to different powder properties, its thermal treatment temp is between 400～1400 ℃.
(3) heart portion material and external cladding material are mixed by weight percentage, carry out the mechanochemistry surface modification, realize bionical (sea anemone) structure of ceramic composite powder by ball milling
Use material to coat with material after mixing heart portion, utilize any equipment in high speed ball milling, vibratory milling or the stirring mill to carry out wet ball grinding, realize the biomimetic features of ceramic composite with outer.Select a kind of as ball-milling medium in zirconium white, aluminum oxide or the agate ball for use, wherein the diameter of ball is between 3 millimeters～5 millimeters., as solvent, agate ball, alumina balls, zirconia ball, carbide ball etc. are as ball-milling medium with deionized water, and the mass concentration of solid phase is between 45～60%, and the weight ratio of solid phase and ball-milling medium is about: 1: 3～5.
At first ball-milling medium is packed in the ball mill, pour the heart portion material and the coating material of preparation biomimetic features pottery usefulness in proportion into, with addition of the deionized water of corresponding abrasive concentration, carried out fine grinding 2～4 hours, and after vacuum filtration, washing and oven dry are prepared into dry powder.
(4) will pass through plasma body sphereization and densification by the powder of ball milling preparation
The using plasma spheroidization device, bionical (sea anemone) structural ceramics composite granule to the mechanochemical reaction preparation carries out plasma body densificationization and further spheroidization processing, plasma generator power is 20～40KW, add a spot of hydrogen as the plasma body carrier gas with argon gas, powder feeding gas is nitrogen, and powder feeding rate is 3～5kg/h.By handling, realize the densification and the metallurgical binding of bionical (sea anemone) structural ceramics composite granule inside, guarantee the uniform distribution between each mutually, make bionical (sea anemone) structural ceramics composite granule further spherical, strengthen its flowability, thereby finish the preparation process of bionical (sea anemone) structural ceramics composite granule.
The present invention has substantive distinguishing features and marked improvement, this preparation method is simple, cost is low, easily realize industrialization production, bionical (sea anemone) structural ceramics composite granule of preparation has the feature of natural biological sea anemone structure, heart portion is the particle of sintered type or Conglobation type pottery and matrix material composition thereof, outer submicron order or the nano level oxide material of coating, metal composite with self-adhesive feature, size-grade distribution is at 5～100 microns, be shaped as spherical or subsphaeroidal structure: combination closely between the inner each component of resulting bionical (sea anemone) structural ceramics composite granule, good fluidity, has good conveying characteristic, can directly apply to thermospray, laser melting coating and sintering, and the thermally sprayed coating of preparation, laser cladding layer and sintered compact have high obdurability and high high-temperature behavior, good thermal shock resistance, wear resistance has better market prospect and commercial value.
Embodiment
Content below in conjunction with method provides specific embodiment:
Embodiment 1 bionical (sea anemone) structure Al
2O
3-TiO
2/ TiO
2The preparation method of ceramic composite powder
At first, utilize well formula resistance furnace to Al
2O
3-TiO
2The reunion powder is heat-treated, and its thermal treatment temp is 800 ℃; Secondly, with the Al after the thermal treatment
2O
3-TiO
2Reunion powder and nano-TiO
2Mixed by weight 97: 3, utilize to stir to grind and carry out wet ball grinding 2h, realize bionical (sea anemone) structure of ceramic composite powder.Select for use agate ball as ball-milling medium, wherein the diameter of ball is 3 millimeters.As solvent, the mass concentration of solid phase is 45% with deionized water, and the weight ratio of solid phase and ball-milling medium is about: 1: 3, stirring the mill rotating speed was 700r/min.Bionical (sea anemone) structural ceramics composite granule that mechanochemical reaction is obtained carries out densification and spheroidization processing then, plasma generator power is 40KW, add a spot of hydrogen as the plasma body carrier gas with argon gas, powder feeding gas is nitrogen, and powder feeding rate is 4kg/h.Finished bionical (sea anemone) structure Al with this
2O
3-TiO
2/ TiO
2The preparation process of ceramic composite powder.Prepare imitative sea anemone structure Al
2O
3-TiO
2/ TiO
2Ceramic composite powder is characterized as: heart portion is Al
2O
3-TiO
2Agglomerating particles coats nano-TiO outward
2, the powder granule size distribution is between 5～80 microns, is solid spherical or subsphaeroidal structure.
Embodiment 2 bionical (sea anemone) structure ZrO
2The preparation method of/NiCrAlY ceramic composite powder
At first, with ZrO
2With the NiCrAlY composite metal powder is to mix at 85: 15 by weight percentage, utilizes to stir mill and carry out wet ball grinding 4h, realizes bionical (sea anemone) structure of ceramic composite powder.Select for use agate ball as ball-milling medium, wherein the diameter of ball is 5 millimeters.As solvent, the mass concentration of solid phase is 50% with deionized water, and the weight ratio of solid phase and ball-milling medium is about: 1: 5, stirring the mill rotating speed was 1000r/min.Bionical (sea anemone) structural ceramics composite granule that mechanochemical reaction is obtained carries out densification and spheroidization processing then, plasma generator power is 36KW, add a spot of hydrogen as the plasma body carrier gas with argon gas, powder feeding gas is nitrogen, and powder feeding rate is 5kg/h.Finished bionical (sea anemone) structure ZrO with this
2The preparation process of/NiCrAlY ceramic composite powder.Prepare imitative sea anemone structure ZrO
2/ NiCrAlY ceramic composite powder is characterized as: heart portion is Y
2O
3Stable ZrO
2Particle coats ultra-fine NiCrAlY composite metal powder outward, and the powder granule size distribution is between 10～85 microns, is solid spherical or subsphaeroidal structure.
Embodiment 3 bionical (sea anemone) structure SIC-Al
2O
3/ Al
2O
3The preparation method of ceramic composite powder
At first, utilize well formula resistance furnace to SiC-Al
2O
3The reunion powder is heat-treated, and its thermal treatment temp is 1400 ℃; Secondly, with the SiC-Al after the thermal treatment
2O
3Reunion powder and nanometer Al
2O
3Mixed by weight 95: 5, utilize to stir to grind and carry out wet ball grinding 5h, realize bionical (sea anemone) structure of ceramic composite powder.Select for use agate ball as ball-milling medium, wherein the diameter of ball is 3 millimeters.As solvent, the mass concentration of solid phase is 60% with deionized water, and the weight ratio of solid phase and ball-milling medium is about: 1: 3, stirring the mill rotating speed was 700r/min.Bionical (sea anemone) structural ceramics composite granule that mechanochemical reaction is obtained carries out densification and spheroidization processing then, plasma generator power is 35KW, add a spot of hydrogen as the plasma body carrier gas with argon gas, powder feeding gas is nitrogen, and powder feeding rate is 3kg/h.Finished bionical (sea anemone) structure SIC-Al with this
2O
3/ Al
2O
3The preparation process of ceramic composite powder.Prepare imitative sea anemone structure SIC-Al
2O
3/ Al
2O
3Ceramic composite powder is characterized as: heart portion is SiC-Al
2O
3Agglomerating particles coats ultra-fine level Al outward
2O
3Powder, powder granule size distribution are between 10～100 microns, are solid spherical or subsphaeroidal structure.
The preparation method of embodiment 5 bionical (sea anemone) structure WC-12Co/Ni/Al ceramic composite powder
At first, utilize well formula resistance furnace that powder that WC-12Co is reunited is heat-treated, its thermal treatment temp is 400 ℃; Secondly, the WC-12Co reunion powder after the thermal treatment is mixed by weight 95: 5 with nanometer/Ni/Al, utilize to stir to grind and carry out wet ball grinding 2h, realize bionical (sea anemone) structure of ceramic composite powder.Select for use agate ball as ball-milling medium, wherein the diameter of ball is 3 millimeters.As solvent, the mass concentration of solid phase is 50% with deionized water, and the weight ratio of solid phase and ball-milling medium is about: 1: 3, stirring the mill rotating speed was 700r/min.Bionical (sea anemone) structural ceramics composite granule that mechanochemical reaction is obtained carries out densification and spheroidization processing then, plasma generator power is 20KW, add a spot of hydrogen as the plasma body carrier gas with argon gas, powder feeding gas is nitrogen, and powder feeding rate is 5kg/h.Finished the preparation process of bionical (sea anemone) structure WC-12Co/Ni/A ceramic composite powder with this.Preparing imitative sea anemone structure WC-12Co/Ni/Al ceramic composite powder is characterized as: heart portion is the WC-12Co agglomerating particles, coats ultra-fine level Ni/Al powder outward, and the powder granule size distribution is between 10～90 microns, is solid spherical or subsphaeroidal structure.
Claims (5)
1; a kind of preparation method of biomimetic features ceramic composite powder; it is characterized in that; determine that at first the biomimetic features ceramic composite powder is the cappelletti packet mode structure of sea anemone biology; its heart portion is the agglomerating particles or the sintered particles of dystectic relatively pottery or Composite Preparation; outer low-melting relatively pottery or the self-adhesive metal composite powder of coating; it is 3～15% and 85～97% that external cladding material and heart portion material account for powder total mass percentage ratio respectively; to prepare biomimetic features ceramics powder body-centered portion material reunion powder then handles through thermal treatment process under 400～1400 ℃ of conditions; again heart portion material and external cladding material are mixed; carry out the mechanochemistry surface modification by 2～4 hours wet ball grinding technology; realize the bionical sea anemone cappelletti packet mode architecture of ceramic composite powder; to be 20～40KW at power by the powder of ball milling preparation at last; powder feeding rate is to carry out plasma body sphereization and densification under 3～5kg/h condition, finishes the preparation of biomimetic features ceramic composite powder.
2, the preparation method of biomimetic features ceramic composite powder according to claim 1, it is characterized in that, described biomimetic features ceramic composite powder, take care portion's material by aluminum oxide, the zirconium white that yttrium oxide or strontium oxide are stable, silicon carbide, when one or more one-tenth in the silicon nitride are grouped into, the outer material that coats is submicron or nano aluminium oxide, titanium oxide, or metal composite Ni/Al, NiCrAl, NiCrAlY, a kind of among the Co, when taking care portion's material and be a kind of in cobalt coated tungsten carbide or the nickel chromium triangle chromium carbide, outside coating material is the Co of ultra-fine level, a kind of among the Ni/Al.
3, the preparation method of biomimetic features ceramic composite powder according to claim 1, it is characterized in that, described thermal treatment process is handled and is meant, handle by thermal treatment process, remove dispersion agent, binding agent, defoamer organic composition and the remaining moisture of reunion powder inside, realize combining closely of reunion powder inside, and keep the yardstick and the shape of its primary particle, used Equipment for Heating Processing is selected well formula, chamber type electric resistance furnace or sintering oven for use, and thermal treatment temp is 400～1400 ℃.
4, the preparation method of biomimetic features ceramic composite powder according to claim 1, it is characterized in that, described ball-milling technology is meant, after heart portion usefulness material and external cladding material mixing, adopt the high speed ball milling, vibratory milling or any equipment that stirs in the mill carry out wet ball grinding, realize the biomimetic features of ceramic composite, select zirconium white for use, a kind of in aluminum oxide or the agate ball as ball-milling medium, wherein the diameter of ball is between 3 millimeters～5 millimeters, with deionized water as solvent, agate ball, alumina balls, zirconia ball, or the carbide ball is as ball-milling medium, the mass concentration of solid phase is between 45～60%, the weight ratio of solid phase and ball-milling medium is: 1: 3～5, at first ball-milling medium is packed in the ball mill, pour the heart portion material and the coating material that prepare biomimetic features pottery usefulness into, with addition of the deionized water of corresponding abrasive concentration, carried out fine grinding 2～4 hours, and after vacuum filtration, washing and oven dry are prepared into dry powder.
5, the preparation method of biomimetic features ceramic composite powder according to claim 1, it is characterized in that, described plasma body sphereization and densification are meant, the using plasma spheroidization device, bionical sea anemone structural ceramics composite granule to the mechanochemical reaction preparation carries out plasma body densificationization and further spheroidization processing, plasma generator power is 20～40KW, add a spot of hydrogen as the plasma body carrier gas with argon gas, powder feeding gas is nitrogen, powder feeding rate is 3～5kg/h, by handling, realize the densification and the metallurgical binding of bionical sea anemone structural ceramics composite granule inside, finish the preparation of bionical sea anemone structural ceramics composite granule.
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| CN105642885B (en) * | 2016-03-30 | 2018-10-30 | 西安交通大学 | A kind of thermal spraying self-adhesive metal alloy powders with covered composite yarn structure |
| CN107236331B (en) * | 2017-06-16 | 2019-07-16 | 国电科学技术研究院武汉电力技术分院 | High-temperature corrosion resistance coating and preparation method thereof and high-temperature corrosion resistance coating and preparation method thereof |
| CN111482611A (en) * | 2019-03-07 | 2020-08-04 | 安徽中体新材料科技有限公司 | Preparation method of spherical tungsten carbide-cobalt powder for 3D printing |
| CN109848407A (en) * | 2019-04-12 | 2019-06-07 | 上海海事大学 | A kind of cobalt-chromium-tungsten alloy cladding tantalum carbide powder and preparation method thereof |
| CN112410719B (en) * | 2020-10-20 | 2023-01-20 | 安徽华飞机械铸锻有限公司 | Wear-resistant heat-resistant steel |
| CN114182129B (en) * | 2021-12-16 | 2022-08-05 | 国网福建省电力有限公司 | High-strength aluminum-based composite material and preparation method thereof |
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