CN110256065A - A kind of dense oxide titanium nano ceramics and its preparation method and application - Google Patents

A kind of dense oxide titanium nano ceramics and its preparation method and application Download PDF

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CN110256065A
CN110256065A CN201910654874.1A CN201910654874A CN110256065A CN 110256065 A CN110256065 A CN 110256065A CN 201910654874 A CN201910654874 A CN 201910654874A CN 110256065 A CN110256065 A CN 110256065A
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nano ceramics
dense oxide
preparation
oxide titanium
titanium nano
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白建光
何天颖
张阳
陈平
黄传卿
柴德亮
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Shaanxi University of Science and Technology
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Shaanxi University of Science and Technology
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Abstract

The invention discloses a kind of dense oxide titanium nano ceramics and its preparation method and application, belong to nano ceramics technical field.Use nano titania for raw material, it is sintered 10min under die material high temperature high pressure, abnormal grain growth is effectively inhibited, removes pressure after sintering, it is cooled to 600 DEG C of heat preservation 4h, product can be promoted further to densify, product crystal grain is tiny, is in Nano grade, product is shunk close to zero simultaneously, product cost can be greatly lowered in short preparation period, have higher economic benefit.The dense oxide titanium nano ceramics of preparation, relative density, crystallite dimension, shrinking percentage performance indicator are excellent.It can be used as stealth material, ultraviolet shielded materials'use.

Description

A kind of dense oxide titanium nano ceramics and its preparation method and application
Technical field
The invention belongs to nano ceramics technical fields, and in particular to a kind of dense oxide titanium nano ceramics and preparation method thereof And application.
Background technique
Dense oxide titanium nano ceramics with its distinctive performance stealth material, in terms of have and answer extensively With.Nanometer ceramic of compact preparation core process problem includes two aspects, first is that guarantee that sintered article inside configuration is nanocrystalline, this Aspect has studied rather maturation at present, i.e., using being rapidly heated between high temperature, short time, sintering and low temperature long-time heat preservation can be real It is existing;Second is densification, and it is that product consistency is difficult to improve that existing main problem is sintered after powder compacting.Ceramic densifying Technique apparently develops relatively slowly at present, or mainly includes hot pressed sintering, liquid-phase sintering using conventional densification process is segmented Three classes are sintered with self- propagating.Sintered body consistency can be improved in hot pressed sintering to a certain extent, but high temperature is due to using stone Black mould strength is low to cause high temperature pressure to be difficult to effectively improve, and high temperature pressure is well below conventional ceramic low temperature moulding pressure;Liquid Phase sintering can also improve consistency to a certain extent, but the introducing of high temperature bond phase affects main body to a certain extent Material property plays, and mutual " conflict " also leads to green body there are certain amounts between Polyhedral Particles during low temperature moulding Stomata, secondly the addition of high-temperature fusant phase causes product deformation larger, is unfavorable for later period application and processing, last titanium oxide high temperature There are small density Anatases to change to big density Rutile Type, also causes sample structure loose to a certain extent, these are right Consistency raising is all unfavorable;For self- propagating sintering is mainly for some special ceramic materials.Thus develop it is a kind of efficiently, Simply, the technique that can effectively improve nano ceramics consistency is current urgent problem to be solved.
Summary of the invention
To solve the above-mentioned problems, the purpose of the present invention is to provide a kind of dense oxide titanium nano ceramics and its preparation sides Method and application, product crystal grain is tiny, is in Nano grade, while product is shunk close to zero, short preparation period can significantly drop Low product cost has higher economic benefit, and the present invention is to be achieved through the following technical solutions:
The invention discloses a kind of methods of dense oxide titanium nano ceramics, are divided into following steps:
1) nano titania is subjected to wet ball grinding, it is dry, it is granulated after sieving;
2) step 1) is granulated obtained particle and is put into die material, 700~900 DEG C are warming up at 150~450Mpa Pressure is removed after heat preservation 10min, 600 DEG C of heat preservation 4h is cooled to, cools to room temperature with the furnace, obtain dense oxide titanium nano ceramics.
Preferably, the average particle size of nano titania is 7nm.
Preferably, the detailed process of wet ball grinding are as follows: alcohol is added into nano titania, using planetary type ball-milling Machine carries out ball milling.
Preferably, the time of wet ball grinding is 30min.
Preferably, dry using rotary dry evaporimeter.
Preferably, sieving was the sieve of 120 mesh.
Preferably, the material of die material is fused alumina zirconia ceramic of compact.
The invention also discloses using the above method preparation dense oxide titanium nano ceramics, relative density be 3.01%~ 4.16%, crystallite dimension is 30~95nm, and shrinking percentage is 0.4511%~0.7312%.
The invention also discloses the application of the dense oxide titanium nano ceramics as stealth material, ultraviolet shielded material.
Compared with prior art, the invention has the following beneficial technical effects:
The method of dense oxide titanium nano ceramics of the invention, sintering time is under die material high temperature high pressure 10min effectively inhibits abnormal grain growth, removes pressure after sintering, is cooled to 600 DEG C of heat preservation 4h, can promote product into The densification of one step, product crystal grain is tiny, is in Nano grade, while product is shunk close to zero, short preparation period can be significantly Product cost is reduced, there is higher economic benefit.
Further, wet ball grinding is carried out using planetary ball mill, in order to the reunion of powder internal particle is reduced, Convenient for later period moulding process.
Further, it is dried using Rotary Evaporators it is possible to prevente effectively from different in general static drying process Grain causes powder to be layered and mix non-uniform phenomenon because density variation causes sinking speed.
Further, die material material is fused alumina zirconia ceramic of compact, has good heat-resistant pressure-resistant performance, improves burning Temperature and pressure when knot.
The dense oxide titanium nano ceramics prepared using the above method of the invention, relative density, crystallite dimension, shrinking percentage Performance indicator is excellent.
When dense oxide titanium nano ceramics of the invention is as stealth material, ultraviolet shielded materials'use, have good Effect.
Specific embodiment
Below with reference to specific embodiment, the present invention is described in further detail, it is described be explanation of the invention and It is not to limit.
A kind of preparation method of dense oxide titanium nano ceramics disclosed by the invention:
Embodiment 1
1) alcohol is added into the nano titania that average particle size is 7nm, wet process is carried out using planetary ball mill Ball milling 30min is dried using rotary dry evaporimeter, crosses 120 meshes after dry and be granulated;
2) obtained particle will be granulated and is put into fused alumina zirconia ceramic of compact die material, keep briquetting pressure 150MPa, heating 600 DEG C of heat preservation 4h are cooled to after to 700 degrees Celsius of heat preservation 10min, cool to room temperature with the furnace, obtain dense oxide titanium nanometer pottery Porcelain.Relative density, crystallite dimension, the shrinking percentage measured is shown in Table 1.
In the situation that remaining condition is constant, the embodiment 2~9 that change sintering temperature and pressure are carried out as shown in table 1, is made The relative density of the dense oxide titanium nano ceramics obtained, crystallite dimension, contraction rate score are as shown in table 1.
Table 1
As can be seen from Table 1, the dense oxide titanium nano ceramics cause with higher that case study on implementation 3,5,6,8 and 9 is prepared Density, nanocrystal size shrink almost very little between 30-95nm.

Claims (9)

1. a kind of preparation method of dense oxide titanium nano ceramics, which is characterized in that be divided into following steps:
1) nano titania is subjected to wet ball grinding, it is dry, it is granulated after sieving;
2) step 1) is granulated obtained particle and is put into die material, 700~900 DEG C of heat preservations are warming up at 150~450Mpa Pressure is removed after 10min, is cooled to 600 DEG C of heat preservation 4h, is cooled to room temperature with the furnace, obtain dense oxide titanium nano ceramics.
2. the preparation method of dense oxide titanium nano ceramics according to claim 1, which is characterized in that nano oxidized titanium valve The average particle size of body is 7nm.
3. the preparation method of dense oxide titanium nano ceramics according to claim 1, which is characterized in that the tool of wet ball grinding Body process are as follows: alcohol is added into nano titania, ball milling is carried out using planetary ball mill.
4. the preparation method of dense oxide titanium nano ceramics according to claim 1, which is characterized in that wet ball grinding when Between be 30min.
5. the preparation method of dense oxide titanium nano ceramics according to claim 1, which is characterized in that dry using rotation Formula dries evaporimeter.
6. the preparation method of dense oxide titanium nano ceramics according to claim 1, which is characterized in that sieving was 120 Purpose sieve.
7. the preparation method of dense oxide titanium nano ceramics according to claim 1, which is characterized in that the material of die material Matter is fused alumina zirconia ceramic of compact.
8. fine and close oxygen prepared by the preparation method using dense oxide titanium nano ceramics described in claim 1~7 any one Change titanium nano ceramics, relative density be 3.01%~4.16%, crystallite dimension be 30~95nm, shrinking percentage be 0.4511%~ 0.7312%.
9. application of the dense oxide titanium nano ceramics according to any one of claims 8 as stealth material, ultraviolet shielded material.
CN201910654874.1A 2019-07-19 2019-07-19 A kind of dense oxide titanium nano ceramics and its preparation method and application Pending CN110256065A (en)

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Cited By (1)

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Publication number Priority date Publication date Assignee Title
CN112174644A (en) * 2020-09-07 2021-01-05 中国科学院上海光学精密机械研究所 Method for pressureless rapid sintering of compact nanocrystalline ceramic

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CN102745977A (en) * 2012-07-25 2012-10-24 武汉理工大学 Method for quickly preparing high-density magnesium oxide nanometer ceramics
CN105645951A (en) * 2016-01-06 2016-06-08 昆明理工大学 Method for promoting phase change of titanium dioxide and inhibiting grain growth
CN106116545A (en) * 2016-06-25 2016-11-16 丁玉琴 A kind of preparation method with amorphous/nanocrystalline structural ceramic material
CN108947493A (en) * 2018-08-09 2018-12-07 苏州市泽镁新材料科技有限公司 A kind of preparation method of the nano oxidized magnesium-based ceramics of high-compactness

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112174644A (en) * 2020-09-07 2021-01-05 中国科学院上海光学精密机械研究所 Method for pressureless rapid sintering of compact nanocrystalline ceramic
CN112174644B (en) * 2020-09-07 2022-05-31 中国科学院上海光学精密机械研究所 Method for rapidly sintering compact nanocrystalline ceramic under no pressure

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Application publication date: 20190920