CN115028436B

CN115028436B - Low-shrinkage high-temperature-resistant alumina material and preparation method and application thereof

Info

Publication number: CN115028436B
Application number: CN202210545386.9A
Authority: CN
Inventors: 陈烁烁; 王高强
Original assignee: Chaozhou Three Circle Group Co Ltd; Nanchong Three Circle Electronics Co Ltd
Current assignee: Chaozhou Three Circle Group Co Ltd; Nanchong Three Circle Electronics Co Ltd
Priority date: 2022-05-19
Filing date: 2022-05-19
Publication date: 2023-03-07
Anticipated expiration: 2042-05-19
Also published as: CN115028436A

Abstract

The invention belongs to the technical field of ceramic materials, and particularly relates to a low-shrinkage high-temperature-resistant aluminum oxide material as well as a preparation method and application thereof. The low-shrinkage high-temperature-resistant alumina material comprises the following components in percentage by mass: 45-55% of fused white corundum, 25-33% of alumina, 13-18% of quartz sand and 5-7% of fluxing agent; the electric melting white corundum comprises spherical corundum and plate-shaped corundum, and the mass ratio of the spherical corundum to the plate-shaped corundum is 1:1 to 2. The spherical corundum and the tabular corundum with different morphologies are simultaneously used, wherein the spherical corundum has low sintering activity and slowly reacts with quartz sand to generate a mullite phase, so that the product has better fracture resistance and excellent high-temperature use performance, and the tabular corundum has relatively high reaction activity, can generate a large number of uniformly distributed small-size grains, and provides the product with higher porosity, low thermal expansion coefficient and excellent thermal shock resistance.

Description

Low-shrinkage high-temperature-resistant alumina material and preparation method and application thereof

Technical Field

The invention belongs to the technical field of ceramic materials, and particularly relates to a low-shrinkage high-temperature-resistant alumina material, and a preparation method and application thereof.

Background

The alumina ceramic substrate has the advantages of high strength, excellent thermal conductivity, good insulativity, thermal shock resistance, chemical corrosion resistance and the like, is a ceramic packaging material with good comprehensive performance and low price, and is widely applied to the electronic fields of semiconductor modules, power control circuits, automotive electronics, aerospace, solar panel components and the like.

The alumina ceramic substrate is molded by a casting method, a dry press molding method, a slip casting method, an isostatic press molding method, or the like. The tape casting method has become an important molding method for the industrial production of alumina ceramic substrates because of high automation degree and production efficiency and simple equipment operation. Generally, in tape casting, alumina powder, a binder, a dispersant and other additives are required to be prepared into slurry with certain solid content and viscosity according to requirements in advance, a green tape with certain toughness and strength is obtained through tape casting, the green tape is cut into green sheets corresponding to the specification of a mold by a punch forming device, and finally, a required ceramic substrate is obtained through high-temperature sintering. In order to inhibit the generation of the defects, a pressing plate is added on a green blank sheet to perform press firing so as to prevent the deformation of the green blank, the self weight of the pressing plate is offset with the thermal stress of the green blank sheet during sintering, so that the effect of improving the warpage is achieved, and the method is adopted by multiple enterprises.

However, the conventional platen has the following problems: (1) The shrinkage is large in single use, the service life is short, and the phenomenon of unmatching with the green body size can occur after short-term use. (2) The porosity of the pressing plate is low, and the glue discharging effect of a green body is influenced after the pressing and the burning so as to generate the defect of glue discharging and cracking. (3) The pressing plate is easy to adhere to products, and the adhesive powder must be coated, so that the process and the cost are increased. How to reduce the shrinkage rate of the pressing plate, improve the glue discharging problem caused by low air holes of the pressing plate and solve the high-temperature adhesion is an urgent problem to be solved in the industry.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art described above. Therefore, the invention provides the low-shrinkage high-temperature-resistant alumina material which has higher porosity, low thermal expansion coefficient and excellent thermal shock resistance.

The invention also provides a preparation method and application of the low-shrinkage high-temperature-resistant aluminum oxide material.

The invention provides a low-shrinkage high-temperature-resistant alumina material, which comprises the following components in percentage by mass:

the electric melting white corundum comprises spherical corundum and tabular corundum, and the mass ratio of the spherical corundum to the tabular corundum is 1:1 to 2.

According to the first aspect of the present invention, at least the following advantageous effects are obtained:

the press plate for press-firing in the alumina ceramic substrate prepared by the prior art has large single-use shrinkage and short service life, and can not be matched with the size of a green body after being used for a short time. The porosity of the pressing plate is low, the glue discharging effect of a green body is influenced after the pressing and the burning to generate the defect of glue discharging crack, mainly because the aluminum oxide particles for manufacturing the pressing plate are small, the burning activity is high, and the particle grading optimization is not carried out on a formula system, so that the density of the pressing plate is high. The pressing plate is easy to adhere to products, the isolating adhesive powder is coated, the process and the cost are increased, and meanwhile, the main phase of the pressing plate is alumina, the pressing plate is made of the same material as a pressed product, and the refractoriness is low.

The spherical corundum and the tabular corundum which are different in morphology and specific in proportion are used simultaneously, wherein the spherical corundum is low in sintering activity and can react with quartz sand to slowly generate a small amount of large-size mullite phase, so that the product is endowed with better fracture resistance and excellent high-temperature service performance, and the tabular corundum is relatively high in reaction activity, can generate a large amount of uniformly distributed small-size grains, and provides the product with higher porosity, low thermal expansion coefficient and excellent thermal shock resistance. Meanwhile, the problems of shrinkage, low porosity, high-temperature adhesion and the like of the product in the press-sintering process can be avoided by controlling the using amount of each component within a certain proportion.

Preferably, the low-shrinkage high-temperature-resistant alumina material comprises the following components in percentage by mass:

preferably, the electrically-fused white corundum is a combination of spherical corundum and tabular corundum, and the mass ratio of the spherical corundum to the tabular corundum is 1:1 to 1.5, more preferably 1: about 1. When the using amount of the spherical corundum is too much, the firing temperature can be greatly improved, and the thermal shock resistance of the product is reduced due to the mismatch of the thermal expansion coefficient of the spherical corundum and the mullite; when the tabular corundum is too much, the compactness of the product is reduced, and the strength is reduced.

Preferably, the spherical corundum is compact spherical corundum with the density of more than 3.9g/cm ³ 。

Preferably, the spherical corundum has an average particle diameter of 6 to 13 μm, more preferably 8 to 11 μm

Preferably, the plate corundum has an equivalent particle diameter of 10 to 15 μm, more preferably 13 to 15 μm.

Preferably, the average particle size of the alumina is 2 to 8 μm, more preferably 3 to 5 μm, and still more preferably 4 to 5 μm.

Preferably, the quartz sand has an average particle size of 3 to 7 μm, more preferably 4 to 6 μm, even more preferably 4 to 5 μm, such as 4.7 μm.

Preferably, the purity of the electrically-fused white corundum, the purity of the alumina and the purity of the quartz sand are independently more than or equal to 95%, more preferably more than or equal to 97%, and even more preferably more than or equal to 99%.

Preferably, the flux comprises magnesium oxide (MgO), manganese dioxide (MnO) ₂ ) Yttrium oxide (Y) ₂ O ₃ ) (ii) a More preferably a combination of magnesium oxide, manganese dioxide, yttrium oxide.

The invention introduces MgO-MnO ₂ -Y ₂ O ₃ The composite fluxing agent can promote the sintering of the electric melting white corundum, mnO ₂ With Al ₂ O ₃ Are close in lattice constant and easily form a solid solution, mn ⁴⁺ Has an ionic radius larger than that of Al ³⁺ Ionic radius of (2) canInducing Al ₂ O ₃ Crystal lattice distortion of the crystal causes Al ₂ O ₃ The crystal lattice is activated, the phenomenon of abnormal growth of crystal grains occurs, and the porosity of the product is increased while the sintering is promoted. MgO plays a role in promoting sintering by forming a liquid phase in the system, and when the amount of the liquid phase formed by MgO is increased, the phenomena of abnormal growth of crystal grains and surrounding of alumina particles by the liquid phase occur, which leads to difficulty in discharging pores at grain boundaries and increase in the porosity of the press plate. Y is ₂ O ₃ Can reduce the viscosity and surface tension of the solid solution, and make the high-temperature liquid phase more easily spread on the solid phase, thereby promoting sintering, and Y ₂ O ₃ The system can be promoted to generate an acicular mullite network, and the strength, the toughness and the thermal shock resistance of the product are greatly improved.

Preferably, the mass ratio of the magnesium oxide to the manganese dioxide to the yttrium oxide is 1:0.4 to 1.5:1.2 to 3.5, more preferably 1:0.5 to 1.3:1.5 to 3.3, more preferably 1:0.53 to 1.27: 1.93-3.14.

Preferably, the magnesium oxide has an average particle size of 2 to 8 μm, more preferably 2 to 5 μm, and still more preferably 2 to 3 μm.

Preferably, the manganese dioxide has an average particle diameter of 1 to 6 μm, more preferably 2 to 5 μm, and still more preferably 2.3 to 3.2 μm.

Preferably, the yttrium oxide has an average particle size of 0.5 to 2 μm, more preferably 0.7 to 1.5 μm, and still more preferably 0.9 to 1.5 μm.

Preferably, the purity of the magnesium oxide, manganese dioxide and yttrium oxide is independently more than or equal to 90%, more preferably more than or equal to 95%, further preferably more than or equal to 98%, such as 99.8%.

the product prepared by the components with the above dosage has higher porosity, low thermal expansion coefficient and excellent thermal shock resistance. Adding amount of fused white corundumLess than 45 percent, low product refractoriness and easy deformation in high temperature use; when the addition amount is more than 55%, the system sintering difficulty is increased rapidly, and the amount of fluxing agent required to be added is increased. When MnO is present ₂ Added in an amount of more than 1.9% and Y ₂ O ₃ When the addition amount is more than 4.7 percent, the alumina crystal lattice is seriously distorted, and the mechanical properties such as the bending strength of the product and the like are rapidly reduced; when MnO is present ₂ Added in an amount of less than 0.8% and Y ₂ O ₃ When the addition amount is less than 2.0%, the alumina crystal grains in the system grow normally and are densified, and the porosity of the product is reduced.

Preferably, the low-shrinkage high-temperature-resistant alumina material comprises the following components in parts by weight:

preferably, the low shrinkage high temperature resistant alumina material component further comprises a binder. The binder accounts for 2-8%, more preferably 3-5% of the total mass of the low-shrinkage high-temperature-resistant alumina material.

Preferably, the binder comprises at least one of polyvinyl butyral (PVB), ethylene methacrylic acid polymer.

Preferably, the low-shrinkage high-temperature-resistant alumina material further includes a dispersant.

Preferably, the dispersant comprises polyvinyl alcohol. The polyvinyl alcohol has the functions of both the solvent and the dispersant, so that the components can be dispersed uniformly, and the stirring effect is improved.

Preferably, the polyvinyl alcohol accounts for 20.0-30.0% of the total mass of the low-shrinkage high-temperature resistant alumina material.

Preferably, the polyvinyl alcohol has a number average molecular weight of from 10 to 15 ten thousand, more preferably from 12.5 to 14.5 ten thousand.

In a second aspect of the present invention, a method for preparing the low shrinkage high temperature resistant alumina material is provided, which includes the following steps:

mixing the alumina and the quartz sand, and performing spray drying granulation to obtain spherical powder;

and mixing the spherical powder with the electro-fused white corundum and the fluxing agent, pre-sintering, and dry-pressing to obtain the low-shrinkage high-temperature-resistant aluminum oxide material.

According to the second aspect of the present invention, at least the following advantageous effects are obtained:

the invention adopts a production process which is different from the prior tape casting process and sintering system, adopts the production process that powder is firstly subjected to spray drying granulation and then presintering, and then is subjected to dry pressing molding, reduces the use of organic matters such as solvent, binder and the like, greatly improves the density of green bodies, and reduces the pollution to the environment. The introduction of the electro-fused white corundum improves the refractoriness of the product, and the product has no sintering activity in the use process, thereby endowing the product with the characteristic of no adhesion with an alumina substrate, and omitting a cover plate powder coating process.

The electric melting white corundum with larger granularity is mixed with the alumina and the quartz sand which are subjected to spray drying granulation and have smaller granularity and then are presintered, volatile components are removed in advance, partial crystalline phases are converted, and a large number of nucleation points are generated, so that the thermal expansion degree in the sintering process is reduced, the formation of a more perfect crystalline grain structure in the sintering process is facilitated, the presintering powder can be subjected to dry pressing molding to obtain a product with high density, and the characteristic of low shrinkage is embodied after sintering.

Preferably, the preparation method of the low-shrinkage high-temperature-resistant alumina material specifically comprises the following steps:

s1, mixing and grinding aluminum oxide and quartz sand to obtain mixed raw powder;

s2, preparing the mixed raw powder into slurry, and performing spray drying granulation on the slurry to obtain spherical powder spraying;

s3, mixing the spherical powder spray with the electric melting white corundum and the fluxing agent, and drying to obtain mixed powder;

s4, heating and pre-burning the mixed powder, and cooling to obtain pre-burned powder;

s5, preparing the pre-sintered powder into dry pressed powder;

s6, preparing a blank sheet by using the dry pressing powder;

and S7, sintering the blank sheet at a high temperature to obtain the low-shrinkage high-temperature-resistant aluminum oxide material product.

Preferably, the grinding mode in the step S1 is ball milling, specifically, alumina and quartz sand are added into a ball milling tank, a ball milling medium and a solvent are added, and the mixture is taken out after ball milling for 15 to 20 hours to obtain mixed micro powder; more preferably, the ball milling time is 8 to 12 hours.

Preferably, the rotation speed of the ball mill is 100-150 r/min, and more preferably 120-150 r/min.

Preferably, the mass ratio of the alumina to the quartz sand to the ball milling medium to the solvent is 1:2 to 3:2 to 3, more preferably 1:2:2.

preferably, the ball milling media comprises corundum balls; the diameter of the corundum ball is 5-10 mm, and the diameter of the corundum ball is more preferably 6-8 mm.

Preferably, the solvent is not limited, and may be any solvent capable of performing ball milling, such as water, alcohols, and the like.

Preferably, the water in the slurry of the step S2 accounts for 5-10% of the mixed raw powder by mass, and more preferably 7-8%.

Preferably, the spray drying granulation in the step S2 is realized by using a spray drying tower, and the air inlet temperature of the spray drying tower is 180-220 ℃, and more preferably 200-210 ℃; the exhaust temperature of the spray drying tower is 100-120 ℃, and more preferably 105-115 ℃.

Preferably, the mixing rotation speed of the step S3 is 700-900 r/min, more preferably about 800 r/min; the mixing time is 1 to 4 hours, more preferably 2 to 3 hours.

Preferably, the temperature of the drying treatment in the step S3 is 120 to 140 ℃, more preferably 125 to 135 ℃. The drying time is 3 to 7 hours, more preferably 4 to 6 hours.

Preferably, polyvinyl alcohol is also added during the mixing process in the step S3. The polyvinyl alcohol plays the role of a solvent and a dispersant, and the powder can be better dispersed in the polyvinyl alcohol and is more uniformly mixed.

Preferably, the temperature of the pre-sintering treatment in the step S4 is 550 to 650 ℃, more preferably about 600 ℃; the calcination time is 3 to 5 hours, and more preferably about 3 hours. The temperature rise rate of the pre-sintering treatment is 3-5 ℃/min, such as 5 ℃/min.

Preferably, a binder may also be added in step S5, specifically, the pre-sintered powder is mixed with the binder to obtain the dry pressed powder. The rotation speed in the mixing process is 100-140 r/min, and is more preferably about 120 r/min.

Preferably, the step S6 is specifically to add the dry pressing powder into a mold of a hydraulic molding machine, and mold and maintain pressure to obtain a pressing plate blank. The pressure for maintaining the pressure is 200-260 MPa, and the more preferable pressure is 240MPa; the dwell time is 1 to 60s, more preferably 30s.

Preferably, the temperature of the high-temperature sintering in the step S7 is 1500-1650 ℃, and more preferably about 1650 ℃; the high-temperature sintering time is 7 to 10 hours, and more preferably about 8 hours.

Preferably, the temperature increasing process in the high-temperature sintering in step S7 is performed in three stages, where the first stage is: the temperature rising rate of room temperature (25 ℃) to 800 ℃ is 4 to 6 ℃/min, and the second stage is as follows: the temperature rise rate of 800-1200 ℃ is 2-4 ℃/min, and the third stage is as follows: the temperature rise rate of 1200-1650 ℃ is 1-2 ℃/min; more preferably, the first stage: the temperature rising rate of room temperature (25 ℃) to 800 ℃ is 5 ℃/min, and the second stage is as follows: the temperature rising rate of 800-1200 ℃ is 3 ℃/min, and the third stage is as follows: the heating rate of 1200-1650 ℃ is 1.5 ℃/min.

In a third aspect of the present invention, the application of the low-shrinkage high-temperature-resistant alumina material in the preparation of a ceramic press plate is provided.

In a fourth aspect of the present invention, an application of the low shrinkage rate high temperature resistant alumina material in the preparation of a ceramic packaging material is provided. The ceramic packaging material comprises an alumina ceramic substrate for packaging electronic components.

In a fifth aspect of the present invention, a method for preparing an alumina ceramic substrate for electronic component packaging includes the following steps: and preparing the alumina slurry into an alumina green sheet, and adding the ceramic pressing plate on the green sheet for press-sintering to obtain the alumina ceramic substrate.

Preferably, the green sheet and the ceramic pressing plate are matched in size, that is, the green sheet and the ceramic pressing plate are the same in shape and area.

The alumina slurry comprises alumina powder, an adhesive, a dispersing agent and other additives, and the components can be prepared into slurry with certain solid content and viscosity according to actual requirements and a formula commonly used in the field. And finally, under the action of the dead weight of the ceramic pressing plate, the required alumina ceramic substrate is obtained through high-temperature sintering. In the process of pressing and sintering, the warping problem of the aluminum oxide ceramic substrate can be improved, the defect of glue discharge cracks is avoided, the pressing plate and the substrate are not adhered, and the pressing plate is pressed and is still matched with the size of a green body after being used for many times.

Preferably, the alumina slurry comprises the following components in percentage by mass,

preferably, the binder in the alumina slurry comprises polyvinyl butyral (PVB).

Preferably, the plasticizer in the alumina slurry comprises dibutyl phthalate (DBP).

Preferably, the dispersant in the alumina slurry comprises polyvinyl alcohol.

Preferably, the solvent in the alumina slurry comprises at least one of ethanol and xylene; more preferred solvents are ethanol and xylene.

Preferably, the mass ratio of ethanol to xylene is 1:1 to 1.2; more preferably 1: about 1.

Preferably, the temperature for pressing and sintering the green sheet added with the ceramic pressing plate is 1500-1600 ℃, and more preferably about 1550 ℃. The time for the press-firing is 4 to 8 hours, and more preferably about 5 hours.

Compared with the prior art, the invention at least has the following beneficial effects:

1. the invention introduces two kinds of electric melting white corundum with different shapes, which are respectively spherical corundum and tabular corundum, wherein the spherical corundum has low sintering activity and slowly reacts with quartz sand to generate a little amount of large-size mullite phase, thereby endowing the product with better fracture resistance and excellent high-temperature service performance, and the tabular corundum has relatively higher reaction activity, can generate more and uniformly distributed small-size crystal grains, and provides the product with higher porosity, low thermal expansion coefficient and excellent thermal shock resistance. At the same time, mgO-MnO is introduced ₂ -Y ₂ O ₃ The composite fluxing agent can promote the sintering of the electro-fused white corundum, reduce the sintering temperature and adjust the electro-fused white corundumThe ratio of corundum to flux is such that the product has low shrinkage, high refractoriness and porosity at the same time.

2. The invention adopts a production process which is different from the prior tape casting process and sintering system, adopts the production process that powder is firstly subjected to spray drying granulation and then presintering, and then is subjected to dry pressing molding, reduces the use of organic matters such as solvent, binder and the like, greatly improves the density of green bodies, and reduces the pollution to the environment. The electric melting white corundum ensures that the refractoriness of the product is more than 1750 ℃, has no sintering activity in the using process, endows the product with the characteristic of non-adhesion with an alumina ceramic substrate, and can omit a cover plate powder coating process.

Drawings

The invention is further described with reference to the following figures and examples, in which:

FIG. 1 is a schematic process flow diagram of the preparation of a press plate according to example 1 of the present invention.

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.

Unless otherwise specified, the specifications of the raw materials used in the embodiments of the present invention are shown in table 1.

TABLE 1 raw material specification parameters

Example 1

In this example, a press plate was prepared, the amounts of the components are shown in table 2, and the specific process is shown in fig. 1, and the process includes the following steps:

1. adding alumina micro powder and quartz sand into a ball milling tank, and mixing the alumina micro powder and the quartz sand according to the following steps: corundum balls: water =1:2:2, adding corundum balls and water according to the mass ratio, wherein the rotating speed of a ball milling tank is 120r/min, and taking out after ball milling for 9 hours to obtain mixed raw powder;

2. adding water accounting for 7-8% of the mass of the mixed raw powder, mixing the mixed raw powder with the water, pulping, adding the mixture into a spray drying tower, and granulating to obtain spherical spray tower powder, wherein the air inlet temperature of the spray drying tower is 205 +/-5 ℃, and the air outlet temperature of the spray drying tower is 110 +/-5 ℃;

3. adding the spherical spray tower powder into a stirring kettle for stirring, and then sequentially adding the electric melting white corundum, mgO and MnO ₂ And Y ₂ O ₃ Then adding 300-400 mL of polyvinyl alcohol (the polyvinyl alcohol is used as a solvent and a dispersing agent, the powder can be well dispersed in the solvent uniformly, the stirring effect is improved) and stirring for 3h at 800r/min, and drying in a ventilation drying oven at 130 +/-5 ℃ to obtain mixed powder;

4. and putting the mixed powder into a muffle furnace after the mixed powder is filled by a crucible, heating to 600 ℃ at the heating rate of 5 ℃/min, preserving the heat for 3h, and cooling along with the furnace to obtain the pre-sintered powder.

5. Adding the pre-sintered powder into a dry powder stirrer, adding an ethylene-methacrylic acid polymer accounting for 4.8 percent of the total mass of the raw materials, and stirring for 2 hours at the rotating speed of 120r/min to obtain dry pressed powder;

6. weighing 14 +/-0.5 g of dry pressing powder, adding the dry pressing powder into a die of a hydraulic forming machine, forming and maintaining the pressure for 30s under the pressure of 240MPa by adopting the die with the specification of 80 x 70mm and the thickness of a cover plate of 0.5mm to obtain a pressing plate green sheet;

7. and (3) putting the green pressing plate sheet into a muffle furnace, heating to 1650 ℃ at the heating rate of 5 ℃/min at room temperature to 800 ℃, 3 ℃/min at 800 to 1200 ℃ and 1.5 ℃/min at 1200 to 1650 ℃, keeping the temperature for 8h, and naturally cooling to room temperature to obtain the ceramic pressing plate.

In the embodiment, the weight ratio of the dense spherical corundum to the tabular corundum in the electric smelting white corundum is 1:1.

examples 2 to 15

In this example, a press plate was prepared, which is different from example 1 in the addition amount of each component, and the specific amount is shown in table 2; the specific procedure was similar to example 1.

Comparative examples 1 to 2

The pressing plate prepared by the comparative example is different from the embodiment in the dosage of the electro-fused white corundum, and the specific dosage is shown in table 2; the specific procedure was similar to example 1.

Comparative examples 3 to 4

The comparison example prepares a pressing plate, and the difference with the example is the different dosage of the alumina micro powder, and the specific dosage is shown in the table 2; the specific procedure was similar to example 1.

Comparative examples 5 to 6

The comparison example prepares a pressing plate, and the difference with the example is the different dosage of the quartz sand, and the specific dosage is shown in the table 2; the specific procedure was similar to example 1.

Comparative examples 7 to 8

The comparative example prepared a press plate, which differs from the examples in the amount of manganese dioxide, the specific amount being shown in table 2; the specific procedure was similar to that of example 1.

Comparative examples 9 to 10

The comparative example prepared a press plate, which is different from the examples in the amount of yttrium oxide, and the specific amount is shown in table 2; the specific procedure was similar to that of example 1.

Comparative example 11

The press plate prepared by the comparative example is different from the press plate prepared by the example 4 in that the fused white corundum only contains compact spherical corundum, and the specific dosage is shown in table 2; the specific procedure was similar to example 1.

Comparative example 12

The press plate prepared by the comparative example is different from the press plate prepared by the example 4 in that the electro-fused white corundum only contains plate-shaped corundum, and the specific dosage is shown in table 2; the specific procedure was similar to that of example 1.

Comparative example 13

The comparison example prepares a press plate, and the difference with the example 4 is that the compact spherical corundum in the electric melting white corundum: tabular corundum =1:3, the specific dosage is shown in table 2; the specific procedure was similar to that of example 1.

Table 2 amounts of components used in examples and comparative examples (mass%/%)

Test examples

The test examples tested the performance of the press plates prepared in the examples and comparative examples, with the test standards as in table 3 and the test results as in table 4.

TABLE 3 test standards for various Properties

TABLE 4 Properties of the press plates prepared in the inventive and comparative examples

As can be seen from Table 4, the press plates prepared in the embodiments 1 to 15 of the present invention all reach the standard in terms of performance, the porosity is not less than 24.68%, and the volume density is not less than 3.73g/cm ³ The breaking strength is more than or equal to 319MPa, and the linear expansion coefficient is 7.8-8.0 multiplied by 10 ^-6 ℃ ^-1 The cycle shrinkage is less than or equal to 0.18 percent, the refractoriness is more than or equal to 1740 ℃, and the thermal shock resistance test has no crack phenomenon, higher porosity, low thermal expansion coefficient and excellent thermal shock resistance.

The fused white corundum used in embodiments 1 to 15 of the present invention contains dense spherical corundum and tabular corundum, and the mass ratio of the dense spherical corundum to the tabular corundum is 1:1, the compact spherical corundum has low sintering activity, slowly reacts with quartz sand to generate larger mullite grains, and can improve the high-temperature strength of the pressing plate and reduce the shrinkage rate; the mullite grains generated by the tabular corundum and the quartz sand are large in quantity, small in grain size and uniform in distribution, and the porosity and the thermal shock resistance of the product can be improved. Whereas the fused white corundum used in comparative example 11 contained only dense spherical corundum in excessThe compact spherical corundum can greatly improve the firing temperature, and the thermal shock resistance of the pressing plate is reduced due to the mismatch of the thermal expansion coefficient of the compact spherical corundum and mullite, so that the prepared pressing plate has cracks, the volume density, the breaking strength and the refractoriness are also obviously reduced, and the performance of the pressing plate does not reach the standard; the fused white corundum used in comparative example 12 contained only tabular corundum, and the fused white corundum used in comparative example 13 contained the fused white corundum in a mass ratio of 1:3, when the dosage of the tabular corundum is excessive, the compactness of the pressing plate is reduced, and the volume density is only 3.01-3.30 g/cm ³ The breaking strength and the refractoriness are also reduced, and the performance of the pressing plate is not up to the standard.

45-55% of fused white corundum and 25-33% of alumina micropowder are used in the embodiments 1-15 of the invention; the pressing plate prepared from 13-18% of quartz sand, 1.0-2.0% of magnesium oxide, 0.8-1.9% of manganese dioxide and 2.0-4.7% of yttrium oxide has low cycle shrinkage, high porosity, good thermal shock resistance and excellent comprehensive performance.

However, when the adding amount of the electro-fused white corundum in the comparative example 1 is less than 45%, the refractoriness of the pressing plate is only 1710 ℃, the pressing plate is easy to deform at the use temperature, and the linear expansion coefficient and the cyclic shrinkage rate do not reach the standard; in the comparative example 2, when the addition amount of the electro-fused white corundum is more than 55%, the system sintering difficulty is increased rapidly, the amount of the added fluxing agent is increased, and the obtained pressing plate has poor thermal shock resistance and cracks. The use amount of the alumina micro powder added in the comparative example 3 is too small (23%), the thermal shock resistance of the pressing plate is deteriorated, and cracks appear; the use amount of the alumina micro powder added in the comparative example 4 is excessive (35%), and the breaking strength and the thermal shock resistance of the pressing plate are both obviously reduced. The quartz sand added in comparative example 5 and comparative example 6 was too little (10%) and too much (20%), respectively, the thermal shock resistance of the obtained press plates was significantly decreased, cracks appeared, and the cycle shrinkage of comparative example 6 was also increased.

The amount of each component in the composite fluxing agent also has an important influence on the performance of the press plate. MnO in comparative example 7 ₂ The addition amount of the composite material is too small (0.5%), and the linear expansion coefficient and the cyclic shrinkage rate of the pressing plate can not reach the standard; mnO in comparative example 8 ₂ Excessive addition (2.2%), porosity, linear expansion coefficient and cyclic shrinkageThe shrinkage rate can not reach the standard. Y in comparative example 9 ₂ O ₃ The adding amount is too small (1.6%), the alumina crystal grains in the system grow and densify normally, the porosity of the pressing plate is reduced obviously and is only 22.11%, and both the porosity and the cyclic shrinkage rate reach the standard; comparative example 10Y ₂ O ₃ When the addition amount is too much (5.7 percent), the aluminum oxide crystal lattice is seriously distorted, the mechanical properties such as the bending strength of the product and the like are rapidly reduced, and the breaking strength, the thermal shock resistance, the linear expansion coefficient and the cyclic shrinkage rate can not reach the standard.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.

Claims

1. The low-shrinkage high-temperature-resistant alumina material is characterized by comprising the following components in percentage by mass:

2. The low-shrinkage high-temperature-resistant alumina material according to claim 1, wherein the average particle diameter of the spherical corundum is 6 to 13 μm, and the equivalent diameters of the plate-shaped corundum are all 10 to 15 μm.

3. The low-shrinkage high-temperature-resistant alumina material as claimed in claim 1, wherein the flux comprises magnesium oxide, manganese dioxide, yttrium oxide.

4. The low-shrinkage high-temperature-resistant aluminum oxide material as claimed in claim 3, wherein the mass ratio of magnesium oxide to manganese dioxide to yttrium oxide is 1:0.4 to 1.5:1.2 to 3.5.

5. The low-shrinkage, high-temperature-resistant alumina material according to claim 1, wherein the alumina has an average particle size of 2 to 8 μm.

6. The low-shrinkage high-temperature-resistant alumina material according to any one of claims 3 or 4, wherein the low-shrinkage high-temperature-resistant alumina material comprises the following components in percentage by mass:

7. the method for preparing a low-shrinkage high-temperature-resistant alumina material according to any one of claims 1 to 6, comprising the steps of:

8. Use of the low-shrinkage, high-temperature-resistant alumina material according to any one of claims 1 to 6 for the production of ceramic press plates.

9. The use of the low-shrinkage, high-temperature resistant alumina material of any one of claims 1 to 6 in the preparation of ceramic packaging materials.

10. A preparation method of an alumina ceramic substrate for packaging electronic components is characterized by comprising the following steps:

preparing an alumina slurry into an alumina green sheet, adding a ceramic pressing plate on the alumina green sheet, and carrying out press-sintering to obtain an alumina ceramic substrate, wherein the ceramic pressing plate is prepared from the low-shrinkage high-temperature-resistant alumina material as claimed in any one of claims 1 to 6.