CN102173827A - Preparation method of zirconium boride-silicon carbide/boron nitride lamellar ultrahigh-temperature ceramic - Google Patents
Preparation method of zirconium boride-silicon carbide/boron nitride lamellar ultrahigh-temperature ceramic Download PDFInfo
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- CN102173827A CN102173827A CN201010622365XA CN201010622365A CN102173827A CN 102173827 A CN102173827 A CN 102173827A CN 201010622365X A CN201010622365X A CN 201010622365XA CN 201010622365 A CN201010622365 A CN 201010622365A CN 102173827 A CN102173827 A CN 102173827A
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Abstract
The invention provides a preparation method of zirconium boride-silicon carbide/boron nitride lamellar ultrahigh-temperature ceramic. The preparation method of the zirconium boride-silicon carbide/boron nitride lamellar ultrahigh-temperature ceramic is characterized by comprising the following steps of: (1) respectively preparing a zirconium boride casting sheet and a boron nitride casting sheet by adopting a casting method: firstly adding a binder and a plasticizer to a solvent, uniformly stirring, then respectively adding zirconium boride ceramic powder and boron nitride boride ceramic powder, uniformly stirring to form casting materials, then carrying out casting forming, and drying and demoulding at room temperature to respectively obtain the zirconium boride casting sheet with the thickness of 200-1000 micrometers and the boron nitride casting sheet with the thickness of 20-100 micrometers; (2) respectively slicing the zirconium boride casting sheet and the boron nitride casting sheet according to the size of a mould; (3) alternately overlapping the zirconium boride slices and the boron nitride slices, placing into a graphite grinding tool, and degreasing in vacuum; and (4) carrying out hot pressed sintering in an argon atmosphere to prepare the lamellar ultrahigh-temperature ceramic. The invention has simple preparation process, low cost and controllable component; and in addition, an obtained material has higher high-temperature oxidation resistance and reaches high fracture toughness at 18.1 MPa.m<1/2>.
Description
Technical field
The invention provides the preparation method of a kind of zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery, belong to the preparing technical field of function ceramics.
Background technology
Zirconium boride ceramic has superior high temperature resistant and corrosion resistance nature and relatively low theoretical density, therefore is considered in ultrahigh-temperature pottery (UHTCs) family one of material of application prospect is arranged most always.At present, zirconium boride ceramic has been widely used as various thermal structures and functional materials, as: the turbine blade in the aircraft industry, magnetohydrodynamic generator electrode etc.But the zirconium boride ceramic fracture toughness property is lower, and tough value only is 4～5MPam
1/2, limited its application under harsh operating environment, as supersonic aircraft nose cone and forward position, scramjet engine hot-end component etc.Therefore, in order to guarantee reliability and the security in the use, must improve the fragility problem of zirconium boride ceramic, thereby improve its thermal shock resistance.Existing at present report about preparation ultrahigh-temperature zirconium boride ceramic, as: the patent No. is that " zirconium boride-carborundum-carbon black ternary high-toughness ultra-temperature ceramic-based composite material and preparation method thereof " intensity of CN101602597A is 132.03～695.54MPa, and fracture toughness property is 2.01～657MPam
1/2The patent No. is that CN101250061B's " preparation method of Zirconia toughened boride ultra-temperature ceramic-based composite material " fracture toughness property reaches 6.0～6.8MPam
1/2, but fracture toughness property still remains further to be improved.
Summary of the invention
The objective of the invention is to provide the preparation method of a kind of zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery for the problem that solves existing zirconium boride 99.5004323A8ure ultrahigh-temperature ceramics toughness difference.Its technical scheme is:
The preparation method of a kind of zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery is characterized in that adopting following steps:
1) adopt casting method to prepare zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet respectively: will to stir in binding agent and the softening agent adding solvent earlier, add zirconium boride ceramic powder and boron nitride ceramics powder more respectively, stir, form the curtain coating material, flow casting molding obtains thick zirconium boride 99.5004323A8ure cast sheet of 200～1000 μ m and the thick boron nitride cast sheet of 20～100 μ m respectively after the drying at room temperature demoulding then;
2) zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet are cut into slices respectively according to the mould size;
3) with zirconium boride 99.5004323A8ure sheet and boron nitride sheet alternately stack put into graphite grinding tool, vacuum degreasing, during degreasing, heat-up rate is 2～3 ℃/min, is warming up to 600～700 ℃, insulation 0.5～1h;
4) hot pressed sintering under argon gas atmosphere, sintering temperature is 1900～2000 ℃, insulation 0.5～2h, pressure is 20～40MPa, promptly gets stratiform ultrahigh-temperature pottery.
The preparation method of described zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery, in the step 1), the zirconium boride ceramic powder is by zirconium boride 99.5004323A8ure powder and silicon carbide powder per-cent 70～90% by volume: 10～30% mix, the particle diameter of zirconium boride 99.5004323A8ure powder is 1～5 μ m, and the particle diameter of silicon carbide powder is 0.5～2 μ m.
The preparation method of described zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery in the step 1), is a basic calculation with zirconium boride ceramic powder weight, takes by weighing binding agent 5～15%, softening agent 5～15% and solvent 100～200% by weight percentage.
The preparation method of described zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery, in the step 1), the boron nitride ceramics powder is by sheet hexagonal boron nitride powder and zirconium boride 99.5004323A8ure powder per-cent 80～100% by volume: 0～20% mixes.
The preparation method of described zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery is a basic calculation with boron nitride ceramics powder weight, takes by weighing binding agent 10～20%, softening agent 10～20% and solvent 500～1000% by weight percentage.
The preparation method of described zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery, binding agent adopts polyvinyl butyral acetal; Softening agent adopts polyoxyethylene glycol; Solvent adopts ethanol.
The present invention compared with prior art has following advantage:
1, in the stratiform ultrahigh-temperature pottery that the present invention makes, the zirconium boride-carborundum layer is a hard formation, boron nitride layer is a soft formation, like this when the ultrahigh-temperature pottery when being subjected to external force, crack propagation to soft formation, just turn to parallel synusia direction expansion, and by soft formation continuation transmitted load, when treating that load increases, crackle just turns to vertical synusia direction expansion again and passes down one deck, like this, crackle just deflects after passing hard formation, has increased the extensions path of crackle, thereby improved the fracture toughness property of material, fracture toughness property is up to 18.1MPam
1/2
2, can control the thickness of zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet by the amount of control solvent, by the bed thickness ratio of adjusting hard formation and soft formation, but the mechanical property of regulating course shape ultrahigh-temperature pottery;
3, zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet is quality controllable, can reach the accurate control to stratiform ultrahigh-temperature pottery moiety by regulating the mass ratio of zirconium boride 99.5004323A8ure, silicon carbide and boron nitride;
4, the boron nitride in the stratiform ultrahigh-temperature pottery has higher high temperature resistance oxidation-resistance, during oxidation, forms the boron oxide protective layer earlier, helps the raising of the oxidation-resistance of ultrahigh-temperature pottery;
5, the sheet hexagonal boron nitride powder has preferred orientation in hot pressing, and lamella helps crack deflection perpendicular to the hot pressing direction in pressurized process.
Description of drawings
Fig. 1 is the SEM photo of the embodiment of the invention 2 gained stratiform ultrahigh-temperature potteries;
Fig. 2 is the SEM photo after the test of the embodiment of the invention 2 gained stratiform ultrahigh-temperature ceramic fracture toughnesses.
Embodiment
Embodiment 1
1, preparation zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet: the preparation of (1) zirconium boride 99.5004323A8ure curtain coating material, elder generation's weighing 2.61 gram polyvinyl butyral acetals, 2.61 gram polyoxyethylene glycol, 52.23 gram ethanol, stir, add the zirconium boride 99.5004323A8ure powder of 42.63 grams, 1 μ m and the silicon carbide powder of 9.60 grams, 0.5 μ m again, stir, form zirconium boride 99.5004323A8ure curtain coating material, wherein zirconium boride 99.5004323A8ure powder and silicon carbide powder are to take by weighing according to 70%: 30% volume percent; (2) preparation of boron nitride curtain coating material, elder generation's weighing 3.03 gram polyvinyl butyral acetals, 3.03 gram polyoxyethylene glycol, 151.7 ethanol, stir, add 18.16 gram boron nitride powders and 12.18 gram zirconium boride 99.5004323A8ure powder again, stir, form boron nitride curtain coating material, wherein boron nitride powder and zirconium boride 99.5004323A8ure powder are to take by weighing according to 80%: 20% volume percent; (3) flow casting molding prolongs zirconium boride 99.5004323A8ure curtain coating material and the materials flow of boron nitride curtain coating respectively, obtains thick zirconium boride 99.5004323A8ure cast sheet of 1000 μ m and the thick boron nitride cast sheet of 100 μ m after the drying at room temperature demoulding;
2, zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet are cut into slices respectively according to the mould size;
3, with zirconium boride 99.5004323A8ure sheet and boron nitride sheet alternately stack put into graphite grinding tool, vacuum degreasing, during degreasing, heat-up rate is 2 ℃/min, is warming up to 700 ℃, insulation 0.5h;
4, adopt the argon gas atmosphere hot pressed sintering then, sintering temperature is 1900 ℃, insulation 2h, and pressure is 20MPa, promptly makes stratiform ultrahigh-temperature pottery.
Embodiment 2
1, preparation zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet: the preparation of (1) zirconium boride 99.5004323A8ure curtain coating material, elder generation's weighing 5.51 gram polyvinyl butyral acetals, 5.51 gram polyoxyethylene glycol, 82.68 gram ethanol, stir, add the zirconium boride 99.5004323A8ure powder of 48.72 grams, 2 μ m and the silicon carbide powder of 6.40 grams, 1 μ m again, stir, form zirconium boride 99.5004323A8ure curtain coating material, wherein zirconium boride 99.5004323A8ure powder and silicon carbide powder are to take by weighing according to 80%: 20% volume percent; (2) preparation of boron nitride curtain coating material, elder generation's weighing 3.98 gram polyvinyl butyral acetals, 3.98 gram polyoxyethylene glycol, 185.64 gram ethanol, stir, add 20.43 gram boron nitride powders and 6.09 gram zirconium boride 99.5004323A8ure powder again, stir, form boron nitride curtain coating material, wherein boron nitride powder and zirconium boride 99.5004323A8ure powder are to take by weighing according to 90%: 10% volume percent; (3) flow casting molding prolongs zirconium boride 99.5004323A8ure curtain coating material and the materials flow of boron nitride curtain coating respectively, obtains thick zirconium boride 99.5004323A8ure cast sheet of 800 μ m and the thick boron nitride cast sheet of 50 μ m after the drying at room temperature demoulding;
2, zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet are cut into slices respectively according to the mould size;
3, with zirconium boride 99.5004323A8ure sheet and boron nitride sheet alternately stack put into graphite grinding tool, vacuum degreasing, during degreasing, heat-up rate is 2.5 ℃/min, is warming up to 650 ℃, insulation 1h;
4, adopt the argon gas atmosphere hot pressed sintering then, sintering temperature is 1950 ℃, insulation 1h, and pressure is 30MPa, promptly makes stratiform ultrahigh-temperature pottery.
Embodiment 3
1, preparation zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet: the preparation of (1) zirconium boride 99.5004323A8ure curtain coating material, elder generation's weighing 8.70 gram polyvinyl butyral acetals, 8.70 gram polyoxyethylene glycol, 116.02 gram ethanol, stir, add the zirconium boride 99.5004323A8ure powder of 54.81 grams, 5 μ m and the silicon carbide powder of 3.20 grams, 2 μ m again, stir, form zirconium boride 99.5004323A8ure curtain coating material, wherein zirconium boride 99.5004323A8ure powder and silicon carbide powder are to take by weighing according to 90%: 10% volume percent; (2) preparation of boron nitride curtain coating material, first weighing 4.54 gram polyvinyl butyral acetals, 4.54 gram polyoxyethylene glycol, 227 gram ethanol stir, and add 22.7 gram boron nitride powders again, stir, and form boron nitride curtain coating material; (3) flow casting molding prolongs zirconium boride 99.5004323A8ure curtain coating material and the materials flow of boron nitride curtain coating respectively, obtains thick zirconium boride 99.5004323A8ure cast sheet of 200 μ m and the thick boron nitride cast sheet of 20 μ m after the drying at room temperature demoulding;
2, zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet are cut into slices respectively according to the mould size;
3, with zirconium boride 99.5004323A8ure sheet and boron nitride sheet alternately stack put into graphite grinding tool, vacuum degreasing, during degreasing, heat-up rate is 3 ℃/min, is warming up to 600 ℃, insulation 1h;
4, adopt the argon gas atmosphere hot pressed sintering then, sintering temperature is 2000 ℃, insulation 0.5h, and pressure is 40MPa, promptly makes stratiform ultrahigh-temperature pottery.
Claims (6)
1. the preparation method of zirconium boride-carborundum/boron nitride stratiform ultrahigh-temperature pottery is characterized in that adopting following steps:
1) adopt casting method to prepare zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet respectively: will to stir in binding agent and the softening agent adding solvent earlier, add zirconium boride ceramic powder and boron nitride ceramics powder more respectively, stir, form the curtain coating material, flow casting molding obtains thick zirconium boride 99.5004323A8ure cast sheet of 200～1000 μ m and the thick boron nitride cast sheet of 20～100 μ m respectively after the drying at room temperature demoulding then;
2) zirconium boride 99.5004323A8ure cast sheet and boron nitride cast sheet are cut into slices respectively according to the mould size;
3) with zirconium boride 99.5004323A8ure sheet and boron nitride sheet alternately stack put into graphite grinding tool, vacuum degreasing, during degreasing, heat-up rate is 2～3 ℃/min, is warming up to 600～700 ℃, insulation 0.5～1h;
4) hot pressed sintering under argon gas atmosphere, sintering temperature is 1900～2000 ℃, insulation 0.5～2h, pressure is 20～40MPa, promptly gets stratiform ultrahigh-temperature pottery.
2. the preparation method of zirconium boride-carborundum as claimed in claim 1/boron nitride stratiform ultrahigh-temperature pottery, it is characterized in that: in the step 1), the zirconium boride ceramic powder is by zirconium boride 99.5004323A8ure powder and silicon carbide powder per-cent 70～90% by volume: 10～30% mix, the particle diameter of zirconium boride 99.5004323A8ure powder is 1～5 μ m, and the particle diameter of silicon carbide powder is 0.5～2 μ m.
3. the preparation method of zirconium boride-carborundum as claimed in claim 1/boron nitride stratiform ultrahigh-temperature pottery, it is characterized in that: in the step 1), with zirconium boride ceramic powder weight is basic calculation, takes by weighing binding agent 5～15%, softening agent 5～15% and solvent 100～200% by weight percentage.
4. the preparation method of zirconium boride-carborundum as claimed in claim 1/boron nitride stratiform ultrahigh-temperature pottery, it is characterized in that: in the step 1), the boron nitride ceramics powder is by sheet hexagonal boron nitride powder and zirconium boride 99.5004323A8ure powder per-cent 80～100% by volume: 0～20% mixes.
5. the preparation method of zirconium boride-carborundum as claimed in claim 1/boron nitride stratiform ultrahigh-temperature pottery, it is characterized in that: with boron nitride ceramics powder weight is basic calculation, takes by weighing binding agent 10～20%, softening agent 10～20% and solvent 500～1000% by weight percentage.
6. as the preparation method of claim 1,3 or 5 described zirconium boride-carborundums/boron nitride stratiform ultrahigh-temperature pottery, it is characterized in that: binding agent adopts polyvinyl butyral acetal; Softening agent adopts polyoxyethylene glycol; Solvent adopts ethanol.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104227823A (en) * | 2014-09-11 | 2014-12-24 | 瑞声精密制造科技(常州)有限公司 | Molding method for multilayer structure ceramic product |
| CN104478436A (en) * | 2014-11-20 | 2015-04-01 | 济南大学 | Preparation method of lamellar silicon carbide/zirconium carbide ultrahigh-temperature ceramic |
| CN104892004A (en) * | 2015-05-18 | 2015-09-09 | 山东理工大学 | Preparation process of highly oriented boron nitride composite material |
| CN105481369A (en) * | 2015-12-10 | 2016-04-13 | 哈尔滨工业大学 | Method for preparing lamellar hexagonal boron nitride composite ceramics with directional thermal conductive characteristics |
Citations (1)
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| CN101844925A (en) * | 2010-05-21 | 2010-09-29 | 李艳 | Process for preparing multilayer ZrB2-SiC complex phase ultrahigh temperature ceramic wafer material by tape casting |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101844925A (en) * | 2010-05-21 | 2010-09-29 | 李艳 | Process for preparing multilayer ZrB2-SiC complex phase ultrahigh temperature ceramic wafer material by tape casting |
Non-Patent Citations (2)
| Title |
|---|
| 《ceramics international》 20100929 Zhihui Lü et al. Processing and properties of ZrB2-SiC composites obtained by aqueous tape casting and hot pressing 第293页摘要 1-6 第37卷, * |
| ZHIHUI LÜ ET AL.: "Processing and properties of ZrB2–SiC composites obtained by aqueous tape casting and hot pressing", 《CERAMICS INTERNATIONAL》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104227823A (en) * | 2014-09-11 | 2014-12-24 | 瑞声精密制造科技(常州)有限公司 | Molding method for multilayer structure ceramic product |
| CN104478436A (en) * | 2014-11-20 | 2015-04-01 | 济南大学 | Preparation method of lamellar silicon carbide/zirconium carbide ultrahigh-temperature ceramic |
| CN104892004A (en) * | 2015-05-18 | 2015-09-09 | 山东理工大学 | Preparation process of highly oriented boron nitride composite material |
| CN105481369A (en) * | 2015-12-10 | 2016-04-13 | 哈尔滨工业大学 | Method for preparing lamellar hexagonal boron nitride composite ceramics with directional thermal conductive characteristics |
| CN105481369B (en) * | 2015-12-10 | 2018-03-30 | 哈尔滨工业大学 | A kind of preparation method with the stratiform hexagonal boron nitride base composite ceramic for orienting thermal conduction characteristic |
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