CN101429013A - Quaternary alumina ceramic material and method for producing the same - Google Patents
Quaternary alumina ceramic material and method for producing the same Download PDFInfo
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- CN101429013A CN101429013A CNA2008102355737A CN200810235573A CN101429013A CN 101429013 A CN101429013 A CN 101429013A CN A2008102355737 A CNA2008102355737 A CN A2008102355737A CN 200810235573 A CN200810235573 A CN 200810235573A CN 101429013 A CN101429013 A CN 101429013A
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Abstract
The invention relates to a quaternionic alumina ceramic material, which comprises the following basic compositions in weight percentage: 94 to 96.5 percent of Al2O3, 2.8 to 4 percent of burnt steatite, 0.5 to 1.5 percent of CaCO3, 0.08 to 0.5 percent of MgO and 0.07 to 0.1 percent of Y2O3. An adhesive is further added into the basic compositions and comprises paraffin and surfactant, and the surfactant is oleic acid and stearic acid or beeswax. Based on 100 in weight percentage, the basic compositions comprise 12 to 16 percent of the paraffin, 0.4 to 0.7 percent of the oleic acid, and 4.95 to 5.05 percent of the stearic acid or the beeswax. The method for processing the materials is to mix the raw materials, add the adhesive into the mixture, make a blank, remove the adhesive, and baking the blank to obtain the finished product. Compared with the prior art, the quaternionic alumina ceramic material has low ceramic generating temperature and high qualification rate. In particular when the ceramic material is applied to a vacuum switch tube, the metallization adaptability in a reducing atmosphere is strong, and the product is not affected by the atmosphere and reaches the requirements of relevant standards.
Description
Technical field
The present invention relates to a kind of stupalith and preparation method thereof, specifically is a kind of quaternary alumina ceramic material and preparation method thereof.
Background technology
Alumina-ceramic is the main class of electronic ceramics, also is one of leading product of vacuum switch, vacuum-capacitor.Aluminum oxide has higher heat conductivity, high-melting-point, high insulation, low-k, low dielectric loss and good packaging process, characteristics such as adaptability, be widely used in microwave electrovacuum, microelectronics, also be high-power IC, H2C semiconducter device, the HIGH-POWERED MICROWAVES electron tube is the important ceramic materials of the high heat conduction components and parts of preparation demand in the nuclear power source always.Domestic preparation 95%AL2O3 pottery in order to form liquid phase sintering, adopts AL2O3-CaO-SiO2 and AL2O3-MgO-two kinds of systems of SiO2 more, uses this system to generate temperature height, ceramic qualification rate is low, and performance is undesirable.
Summary of the invention
In order to solve the above-mentioned problems in the prior art, the invention provides a kind of quaternary alumina ceramic material and preparation method thereof, concrete technical scheme is as follows:
A kind of quaternary alumina ceramic material, basal component comprise (according to weight percent meter): Al
2O
394~96.5%, burn talcum 2.8~4%, CaCO
30.5~1.5%, MgO 0.08~0.5% and Y
2O
30.07~0.1%.Above-mentioned basal component adds caking agent again; Described caking agent comprises paraffin and tensio-active agent, and tensio-active agent is oleic acid and stearic acid or beeswax.The weight of described basal component is in 100, and the paraffin consumption is 12~16, and the oleic acid consumption is 0.4~0.7, and stearic acid or beeswax consumption are 5 ± 0.05.
A kind of working method of above-mentioned quaternary alumina ceramic material: raw material through mixing, adding caking agent, base, eliminating caking agent and firing process, is obtained finished product at last.
The basal component of raw material comprises (according to weight percent meter): Al
2O
394~96.5%, burn talcum 2.8~4%, CaCO
30.5~1.5%, MgO 0.08~0.5% and Y
2O
30.07~0.1%.Described raw material is a powder-material after mixing, its median size≤5um.Described caking agent comprises paraffin and tensio-active agent, and tensio-active agent is oleic acid and stearic acid or beeswax.
Above-mentioned raw materials blended method is, raw material mixed with grinding aid, through ball milling, sieve and handle the powder-material that obtains median size≤5um; Described ball milling is to be that 1:2 carries out the dry type ball milling in ball mill according to material ball ratio; Drum's speed of rotation is 28~32 rev/mins, and the ball milling time is 20~26 hours.Described grinding aid is oleic acid, phosphatide, lipid acid or trolamine, and concrete consumption does not have particular requirement.
After powder-material heating dewatered, mix with caking agent again, practiced system 2 hours through vacuum stripping then, vacuum tightness is-0.1MPa old 72 hours.
Described moulding is to adopt hot die-casting molding, and pressure is 0.3~0.4MPa.This step is finished in hot injection moulding machine.
Described eliminating caking agent is temperature rise rate: normal temperature~200 ℃, and 10 ℃/hour, 200 ℃ of insulations 3 hours; 200~350 ℃, 15~20 ℃/hour; 350~600 ℃, 25~30 ℃/hour; 600~1080 ℃, 30~35 ℃/hour, 1080 ℃ of insulations 2 hours.This step is finished in the de-waxing kiln.
Described burning till is temperature rise rate: normal temperature~500 ℃, 20 ℃/hour; 500~1350 ℃, 25 ℃/hour; 1350~1650 ℃, 30 ℃/hour, get final product at 2 hours postcooling of 1650 ℃ of insulations.This step is finished in tunnel furnace.
Also be provided with surface treatment, the red check of suction and cleaning step after burning till end: after grinding off the ceramic surface emergy earlier, again pottery is put into and inhaled red check after fuchsin solution soaks the regulation duration, at last the pottery that is up to the standards is cleaned with washing powder solution and poach gets product after totally.
Through above-mentioned steps, make ceramic chemical constitution by weight percentage: Al
2O
393.5~96.5%; MgO:1.6~2.5%; SiO
2: 1.8~2.6%; CaO:0.5~1.5%; Be a kind of Al
2O
3-CaO-MgO-SiO
2Quaternary system.
In the above-mentioned steps, behind the adding grinding aid, can form complete unit molecule of one deck or polymolecular film, stop fine grain gathering, also just improve the efficient of pulverizing and the flowability of raw material at particle outside surface adsorption activity medium.
In the above-mentioned steps, caking agent comprises paraffin and tensio-active agent.Tensio-active agent can improve the flowability of slurry and prevent blank cracking
In the above-mentioned steps, old 72 hours, make the migration of the inherent molecule of raw material and strengthened the consistence of organizing.
In the above-mentioned steps, getting rid of caking agent is that organic adhesive all will be burnt in the past at 400 ℃, becomes gaseous volatilization.Should note keeping oxidizing atmosphere in the kiln in this stage, just can make the caking agent reduction.It is too urgent to heat up, and might make the product cracking.
In the above-mentioned steps, burn till and just utilize Al
2O
3Solid phase diffusion mechanism.Whole burning till all carried out in tunnel furnace, comprises the whole process in stages such as preheating, roasting, cooling.
In present method, add small amounts of additives by forming in the proportioning, and select suitable wax and tensio-active agent at raw material, and the optimal addn of definite tensio-active agent, the add-on that wax is starched paraffin in the blank improved.By reducing the content of paraffin in the wax slurry blank, can reduce the shrinking percentage of ceramic body after the moulding, thereby create conditions for preparation high performance and big size alumina ceramic material.
Compared with prior art, the present invention's pottery generation temperature is low, qualification rate is high.When especially being applied to vacuum switch tube, metallization adaptability is strong in reducing atmosphere, and product is not influenced by atmosphere, reaches " the effective ceramic cartridge of vacuum switch " SJ/T11246-2001 standard.After testing, it is as shown in the table that the present invention obtains the technical indicator of finished product.
Table 1:
Volume density | 3.6~3.7g/cm 3 |
Folding strength | ≥280MPa |
The sealing strength of ceramic-metal | ≥100MPa |
Linear expansivity | 6.5~7.5×10 -6/℃ |
Dielectric loss | ≤4×10 -4 |
Volume specific resistance | ≥10 14Ω·cm(25℃) ≥10 13Ω·cm(100℃) |
Dielectric strength | ≥20KV/mm |
Thermal conductivity | ≥16W/(m·K) |
Producible maximum product size | ≥φ260mm |
Embodiment
The invention will be further described below in conjunction with specific embodiment.
Example 1: raw material is got Al
2O
394%, CaCO
31.5%, MgO 0.5% and Y
2O
30.1%, surplus is to burn talcum.Caking agent is got paraffin, oleic acid and stearic acid, and wherein the paraffin consumption is 12% of a raw material, and the oleic acid consumption is 0.4% of a raw material, and stearic acid dosage is 0.45% of a raw material.
Above-mentioned raw materials through mixing, adding caking agent, base, eliminating caking agent and firing process, is obtained finished product at last.
Raw material is mixed with grinding aid, obtain the powder-material of median size≤5um through ball milling, the processing of sieving; Described ball milling is to be that 1:2 carries out the dry type ball milling in ball mill according to material ball ratio; Drum's speed of rotation is 28 rev/mins, and the ball milling time is 20 hours.Described grinding aid is an oleic acid, and concrete consumption does not have particular requirement.
After powder-material heating dewatered, mix with caking agent again, practiced system 2 hours through vacuum stripping then, vacuum tightness is-0.1MPa old 72 hours.
Described moulding is to adopt hot die-casting molding, and pressure is 0.3MPa.This step is finished in hot injection moulding machine.
Described eliminating caking agent is temperature rise rate: normal temperature~200 ℃, and 10 ℃/hour, 200 ℃ of insulations 3 hours; 200~350 ℃, 15 ℃/hour; 350~600 ℃, 25 ℃/hour; 600~1080 ℃, 30 ℃/hour, 1080 ℃ of insulations 2 hours.This step is finished in the de-waxing kiln.
Described burning till is temperature rise rate: normal temperature~500 ℃, 20 ℃/hour; 500~1350 ℃, 25 ℃/hour; 1350~1650 ℃, 30 ℃/hour, get final product at 2 hours postcooling of 1650 ℃ of insulations.This step is finished in tunnel furnace.
Also be provided with surface treatment, the red check of suction and cleaning step after burning till end: after grinding off the ceramic surface emergy earlier, again pottery is put into and inhaled red check after fuchsin solution soaks the regulation duration, at last the pottery that is up to the standards is cleaned with washing powder solution and poach gets product after totally.
Example 2: raw material is got Al
2O
396.5%, CaCO
30.5%, MgO 0.08% and Y
2O
30.07%, surplus is to burn talcum.Caking agent is got paraffin, oleic acid and stearic acid, and wherein the paraffin consumption is 16% of a raw material, and the oleic acid consumption is 0.7% of a raw material, and stearic acid dosage is 0.55% of a raw material.
Above-mentioned raw materials through mixing, adding caking agent, base, eliminating caking agent and firing process, is obtained finished product at last.
Raw material is mixed with grinding aid, obtain the powder-material of median size≤5um through ball milling, the processing of sieving; Described ball milling is to be that 1:2 carries out the dry type ball milling in ball mill according to material ball ratio; Drum's speed of rotation is 32 rev/mins, and the ball milling time is 26 hours.Described grinding aid is a phosphatide, and concrete consumption does not have particular requirement.
After powder-material heating dewatered, mix with caking agent again, practiced system 2 hours through vacuum stripping then, vacuum tightness is-0.1MPa old 72 hours.
Described moulding is to adopt hot die-casting molding, and pressure is 0.4MPa.This step is finished in hot injection moulding machine.
Described eliminating caking agent is temperature rise rate; Normal temperature~200 ℃, 10 ℃/hour, 200 ℃ of insulations 3 hours; 350 ℃, 20 ℃/hour; 350~600 ℃, 30 ℃/hour; 600~1080 ℃, 35 ℃/hour, 1080 ℃ of insulations 2 hours.This step is finished in the de-waxing kiln.
Described burning till is temperature rise rate: normal temperature~500 ℃, 20 ℃/hour; 500~1350 ℃, 25 ℃/hour; 1350~1650 ℃, 30 ℃/hour, get final product at 2 hours postcooling of 1650 ℃ of insulations.This step is finished in tunnel furnace.
Also be provided with surface treatment, the red check of suction and cleaning step after burning till end: after grinding off the ceramic surface emergy earlier, again pottery is put into and inhaled red check after fuchsin solution soaks the regulation duration, at last the pottery that is up to the standards is cleaned with washing powder solution and poach gets product after totally.
Example 3: raw material is got Al
2O
395%, CaCO
31%, MgO 0.25% and Y
2O
30.09%, surplus is to burn talcum.Caking agent is got paraffin, oleic acid and stearic acid, and wherein the paraffin consumption is 14% of a raw material, and the oleic acid consumption is 0.5% of a raw material, and stearic acid dosage is 0.5% of a raw material.
Above-mentioned raw materials through mixing, adding caking agent, base, eliminating caking agent and firing process, is obtained finished product at last.
Raw material is mixed with grinding aid, obtain the powder-material of median size≤5um through ball milling, the processing of sieving; Described ball milling is to be that 1:2 carries out the dry type ball milling in ball mill according to material ball ratio; Drum's speed of rotation is 30 rev/mins, and the ball milling time is 23 hours.Described grinding aid is a trolamine, and concrete consumption does not have particular requirement.
After powder-material heating dewatered, mix with caking agent again, practiced system 2 hours through vacuum stripping then, vacuum tightness is-0.1MPa old 72 hours.
Described moulding is to adopt hot die-casting molding, and pressure is 0.35MPa.This step is finished in hot injection moulding machine.
Described eliminating caking agent is temperature rise rate: normal temperature~200 ℃, and 10 ℃/hour, 200 ℃ of insulations 3 hours; 200~350 ℃, 18 ℃/hour; 350~600 ℃, 28 ℃/hour; 600~1080 ℃, 32 ℃/hour, 1080 ℃ of insulations 2 hours.This step is finished in the de-waxing kiln.
Described burning till is temperature rise rate: normal temperature~500 ℃, 20 ℃/hour; 500~1350 ℃, 25 ℃/hour; 1350~1650 ℃, 30 ℃/hour, get final product at 2 hours postcooling of 1650 ℃ of insulations.This step is finished in tunnel furnace.
Also be provided with surface treatment, the red check of suction and cleaning step after burning till end: after grinding off the ceramic surface emergy earlier, again pottery is put into and inhaled red check after fuchsin solution soaks the regulation duration, at last the pottery that is up to the standards is cleaned with washing powder solution and poach gets product after totally.
In the above-mentioned example 1,2 and 3, paraffin and tensio-active agent melt earlier and mix with powder-material.
After testing, the technical indicator of finished product is as shown in the table:
Table 2:
Volume density | 3.678g/cm 3 |
Folding strength | 296MPa |
Linear expansivity (room temperature~500 ℃) | 7.11×10 -6/℃ |
Dielectric loss | 2.8×10 -4 |
Volume specific resistance | ≥10 14Ω·cm(25℃) ≥10 13Ω·cm(100℃) |
Dc breakdown intensity | 23KV/mm |
Claims (9)
1, a kind of quaternary alumina ceramic material is characterized in that basal component by weight percentage, comprising: Al
2O
394~96.5%, burn talcum 2.8~4%, CaCO
30.5~1.5%, MgO 0.08~0.5% and Y
2O
30.07~0.1%; Above-mentioned basal component adds caking agent again; Described caking agent comprises paraffin and tensio-active agent, and tensio-active agent is oleic acid and stearic acid or beeswax.
2, quaternary alumina ceramic material according to claim 1, the weight that it is characterized in that described basal component are in 100, and the paraffin consumption is 12~16, and the oleic acid consumption is 0.4~0.7, and stearic acid or beeswax consumption are 5 ± 0.05.
3, the working method of the described quaternary alumina ceramic material of a kind of claim 1 is characterized in that raw material obtaining finished product at last through mixing, adding caking agent, base, eliminating caking agent and firing process; The basal component of raw material and weight percent are Al
2O
394~96.5%, burn talcum 2.8~4%, CaCO
30.5~1.5%, MgO0.08~0.5% and Y
2O
30.07~0.1%; Described raw material is a powder-material after mixing, its median size≤5um; Described caking agent comprises paraffin and tensio-active agent, and tensio-active agent is oleic acid and stearic acid or beeswax.
4, the working method of quaternary alumina ceramic material according to claim 3 is characterized in that raw material blended method is, raw material is mixed with grinding aid, obtains the powder-material of median size≤5um through ball milling, the processing of sieving;
Described ball milling is to be that 1:2 carries out the dry type ball milling in ball mill according to material ball ratio; Drum's speed of rotation is 28~32 rev/mins, and the ball milling time is 20~26 hours;
Described grinding aid is oleic acid, phosphatide, lipid acid or trolamine.
5, the working method of quaternary alumina ceramic material according to claim 3 after it is characterized in that powder-material heating dewatered, mixes with caking agent again, practices system 2 hours through vacuum stripping then, and vacuum tightness is-0.1MPa old 72 hours.
6, the working method of quaternary alumina ceramic material according to claim 3 is characterized in that described moulding is, adopts hot die-casting molding, and pressure is 0.3~0.4MPa.This step is finished in hot injection moulding machine.
7, the working method of quaternary alumina ceramic material according to claim 3 is characterized in that described eliminating caking agent is temperature rise rate: normal temperature~200 ℃, and 10 ℃/hour, 200 ℃ of insulations 3 hours; 200~350 ℃, 15~20 ℃/hour; 350~600 ℃, 25~30 ℃/hour; 600~1080 ℃, 30~35 ℃/hour, 1080 ℃ of insulations 2 hours.
8, the working method of quaternary alumina ceramic material according to claim 3 is characterized in that described burning till is temperature rise rate: normal temperature~500 ℃, 20 ℃/hour; 500~1350 ℃, 25 ℃/hour; 1350~1650 ℃, 30 ℃/hour, get final product at 2 hours postcooling of 1650 ℃ of insulations.
9, the working method of quaternary alumina ceramic material according to claim 3, also be provided with surface treatment, the red check of suction and cleaning step after it is characterized in that burning till end: after grinding off the ceramic surface emergy earlier, again pottery is put into and inhaled red check after fuchsin solution soaks the regulation duration, at last the pottery that is up to the standards is cleaned with washing powder solution and poach promptly gets product after totally.
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Cited By (5)
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CN103086702A (en) * | 2011-11-18 | 2013-05-08 | 常熟市创新陶瓷有限公司 | Aluminum oxide ceramic and manufacturing method thereof |
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2008
- 2008-11-21 CN CNA2008102355737A patent/CN101429013A/en active Pending
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103086702A (en) * | 2011-11-18 | 2013-05-08 | 常熟市创新陶瓷有限公司 | Aluminum oxide ceramic and manufacturing method thereof |
CN103925567A (en) * | 2014-04-03 | 2014-07-16 | 深圳市昭城电子有限公司 | Ceramic LED lamp tray and manufacturing method thereof |
CN103925567B (en) * | 2014-04-03 | 2018-01-16 | 深圳市昭城电子有限公司 | A kind of LED ceramic tray and preparation method thereof |
CN105000869A (en) * | 2015-06-26 | 2015-10-28 | 新化县恒睿电子陶瓷科技有限公司 | Manufacturing method of ceramic bracket for magnetic suspension variable frequency centrifuge coil |
CN105000869B (en) * | 2015-06-26 | 2018-04-24 | 新化县恒睿电子陶瓷科技有限公司 | A kind of manufacture method of magnetic suspension variable frequency centrifuge coil ceramics bracket |
CN112238520A (en) * | 2020-11-06 | 2021-01-19 | 湖南先导电子陶瓷科技产业园发展有限公司 | Hot-pressing electronic ceramic blank injection equipment and process |
CN112374867A (en) * | 2020-11-13 | 2021-02-19 | 娄底市安地亚斯电子陶瓷有限公司 | Ceramic surface hot-press casting forming slurry and preparation process thereof |
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