阅读说明：本技术 陶瓷连接用微晶玻璃钎料及其制备方法和陶瓷连接方法 (Microcrystalline glass brazing filler metal for ceramic connection, preparation method thereof and ceramic connection method ) 是由 路建宁 骆智超 林颖菲 王娟 郑开宏 于 2021-11-11 设计创作，主要内容包括：本发明公开了陶瓷连接用微晶玻璃钎料及其制备方法和陶瓷连接方法。陶瓷连接用微晶玻璃钎料主要是由玻璃相和Al-B-O系氧化物晶体组成的多相混合物,该玻璃钎料的原材料组成成分按质量百分含量计包括：35～45％Al-(2)O-(3)、25～35％B-(2)O-(3)、15～25％SiO-(2)、3～15％碱土金属氧化物。该制备方法具体包括将原料均匀混合,快速熔炼为玻璃熔体,然后进行水淬、磨粉。陶瓷连接方法,采用本发明提供的微晶玻璃钎料连接陶瓷材料。利用上述微晶玻璃钎料连接以氧化铝为基体的陶瓷材料时,通过玻璃钎料中组元间的反应、钎料与氧化物陶瓷母材之间的反应生成细长晶须实现母材稳定、可靠的连接,连接接头强度高,接头处残余应力小。(The invention discloses a microcrystalline glass solder for ceramic connection, a preparation method thereof and a ceramic connection method. The microcrystalline glass solder for ceramic connection is a multi-phase mixture mainly composed of a glass phase and Al-B-O series oxide crystals, and comprises the following raw material components in percentage by mass: 35-45% of Al 2 O 3 、25～35％B 2 O 3 、15～25％SiO 2 3 to 15% of an alkaline earth metal oxide. The preparation method specifically comprises the steps of uniformly mixing the raw materials, rapidly smelting the mixture into a glass melt, and then carrying out water quenching and grinding. The ceramic connecting method adopts the microcrystalline glass solder provided by the invention to connect ceramic materials. When the microcrystalline glass solder is used for connecting ceramic materials taking alumina as a matrix, the stable and reliable connection and connection of parent metals are realized by generating slender whiskers through the reaction between the components in the glass solder and the reaction between the solder and the oxide ceramic parent metalThe joint has high strength and small residual stress at the joint.)

1. The microcrystalline glass solder for ceramic connection is characterized by being a multi-phase mixture mainly composed of a glass phase and Al-B-O series oxide crystals, and the glass solder comprises the following raw materials in percentage by mass: 35-45% of Al₂O₃、25～35％B₂O₃、15～25％SiO₂3 to 15% of alkaline earth metal oxide, 1 to 3% of alkali metal oxide and less than 2% of alkali metal oxideInevitable impurities, the alkaline earth metal oxide including at least one of MgO and CaO, and the alkali metal oxide including Na₂O and K₂At least one of O.

2. The microcrystalline glass solder according to claim 1, wherein the Al-B-O based oxide crystal mainly contains Al₄B₂O₉、Al₁₈B₄O₃₃And Al₅BO₉。

3. A method for preparing a microcrystalline glass solder for ceramic bonding according to claim 1 or 2, comprising:

mixing Al according to a predetermined mixture ratio₂O₃、B₂O₃、SiO₂Uniformly mixing the alkaline earth metal oxide and the alkali metal oxide, rapidly increasing the temperature to 1200-1400 ℃ at the heating rate of 50-200 ℃/min, and preserving the temperature for 5-10 min to smelt into glass melt;

water quenching the glass melt to obtain a glass frit;

and preparing the glass frit into the microcrystalline glass solder.

4. The preparation method of the microcrystalline glass solder for ceramic connection according to claim 3, wherein the uniform mixing is to place the raw materials in a three-dimensional motion mixer and mix for 2-5 hours.

5. The method for producing a microcrystalline glass solder for ceramic bonding according to claim 3, wherein the melting is performed in an induction heating furnace;

preferably, the mixed raw materials are placed in a graphite crucible of an induction heating furnace for smelting.

6. The preparation method of the microcrystalline glass solder for ceramic connection according to claim 3, wherein the water quenching of the glass melt further comprises water filtering and drying, and then the glass frit is obtained;

preferably, the drying temperature is 100-120 ℃, and the drying time is 1-2 h.

7. The method for preparing the microcrystalline glass solder for ceramic connection according to claim 3, wherein the glass frit is prepared into the microcrystalline glass solder by crushing, ball milling and screening;

preferably, the crushing, ball milling and sieving are in particular:

crushing the glass frit into small glass blocks with the particle size of less than 1 mm;

and ball-milling the small glass blocks, and sieving to obtain powder with the particle size of less than 10 microns.

8. The preparation method of the microcrystalline glass solder for ceramic connection according to claim 7, wherein in the ball milling process, the small glass blocks are placed in a corundum ball milling tank for ball milling, the ball-to-material ratio is 5-10: 1, the ball milling rotation speed is 350-450 r/min, and the ball milling time is 30-90 min;

preferably, the milling balls are zirconia balls.

9. A ceramic connection method, characterized in that a ceramic material is connected by using the microcrystalline glass solder for ceramic connection as defined in claim 1 or 2 or the microcrystalline glass solder for ceramic connection prepared by the preparation method as defined in any one of claims 3 to 8, wherein the ceramic material to be connected is a ceramic material using alumina as a matrix; preferably, the ceramic material is Al₂O₃At least one of ZTA and ARZ.

10. The ceramic joining method according to claim 9, comprising:

uniformly mixing the microcrystalline glass brazing filler metal and a binder, uniformly coating the mixture on a clean ceramic surface, and drying and forming to obtain a ceramic to-be-connected piece;

carrying out brazing treatment on the ceramic to-be-connected piece in an air furnace, and cooling along with the furnace to obtain ceramic after brazing connection;

preferably, the binder is at least one of water glass, epoxy adhesive and polyurethane adhesive;

preferably, the drying and forming temperature is 60-80 ℃;

preferably, the brazing treatment temperature is 1300-1350 ℃, and the holding time is 3-5 h.

Technical Field

The invention relates to the technical field of ceramic materials, in particular to a microcrystalline glass solder for ceramic connection, a preparation method thereof and a ceramic connection method.

Background

The ceramic material has excellent performances of high melting point, high hardness, high wear resistance, low linear expansion coefficient, good corrosion resistance to acid, alkali, salt and high temperature and the like, and can be widely applied to the industries of machinery, electronics, chemical industry, medicine, aerospace and the like as a structural material and a functional material. At present, the methods for connecting ceramics mainly comprise mechanical connection, transient liquid phase connection, diffusion welding, brazing, microwave heating connection methods and the like, wherein the brazing method is the connection method which is most researched and most widely applied due to lower brazing heating temperature and smaller weldment deformation.

Solder is an important factor in ceramic brazing, and the performance of the solder greatly determines the quality of a brazed joint. The middle layer for connecting the ceramic material mainly comprises an adhesive, a metal-based brazing filler metal, a glass brazing filler metal and the like. The adhesive has the advantages of no high temperature resistance, easy aging and low strength; the corrosion resistance of the metal-based brazing filler metal is poor, the difference between the thermal expansion coefficient of the metal intermediate layer and the ceramic base metal is large, and the residual stress of a brazed joint is large; the glass brazing filler metal has high strength, strong corrosion resistance and good thermal expansion coefficient matching with the ceramic base material.

The microcrystalline glass solder is a multiphase mixture consisting of a microcrystalline phase and a glass phase, has excellent properties of ceramics and glass, and has the advantages of high strength, strong corrosion resistance, high use temperature, large-range adjustable thermal expansion coefficient, excellent chemical compatibility with a ceramic substrate and the like. However, the high temperature and long time required for smelting the existing glass brazing filler metal cause the violent component reaction among the brazing filler metal raw materials, and the chemical reaction degree between the finally prepared glass brazing filler metal and the ceramic base metal is low, so that the bonding strength among the base metals is low, and the residual stress at the joint is large.

In view of this, the present application is specifically made.

Disclosure of Invention

The invention aims to provide a microcrystalline glass solder for ceramic connection, a preparation method thereof and a ceramic connection method.

The invention is realized by the following steps:

in a first aspect, the invention provides a microcrystalline glass solder for ceramic connection, which is a multi-phase mixture mainly composed of a glass phase and Al-B-O series oxide crystals, and comprises the following raw material components in percentage by mass: 35-45% of Al₂O₃、25～35％B₂O₃、15～25％SiO₂3-15% of alkaline earth metal oxide, 1-3% of alkali metal oxide and less than 2% of unavoidable impurities, wherein the alkaline earth metal oxide comprises at least one of MgO and CaO, and the alkali metal oxide comprises Na₂O and K₂At least one of O.

In an alternative embodiment, the Al-B-O based oxide crystal consists essentially of Al₄B₂O₉、Al₁₈B₄O₃₃And Al₅BO₉。

In a second aspect, an embodiment of the present invention provides a method for preparing a microcrystalline glass solder for ceramic connection, where the method is used to prepare the above microcrystalline glass solder for ceramic connection, and includes:

mixing Al according to a predetermined mixture ratio₂O₃、B₂O₃、SiO₂Uniformly mixing the alkaline earth metal oxide and the alkali metal oxide, rapidly increasing the temperature to 1200-1400 ℃ at the heating rate of 50-200 ℃/min, and preserving the temperature for 5-10 min to smelt into glass melt;

water quenching the glass melt to obtain a glass frit;

and preparing the glass frit into the microcrystalline glass solder.

In an optional embodiment, the uniform mixing is to place the raw materials in a three-dimensional motion mixer, and mix the materials for 2-5 hours.

In an alternative embodiment, the melting is performed in an induction heating furnace.

In an alternative embodiment, the mixed feedstock is placed in a graphite crucible of an induction heating furnace for melting.

In an alternative embodiment, the glass melt is water quenched, including draining and drying, to provide a glass frit.

In an optional embodiment, the drying temperature is 100-120 ℃, and the drying time is 1-2 h.

In an alternative embodiment, the glass frit is formed into a glass ceramic solder by crushing, ball milling and sieving.

In an alternative embodiment, the crushing, ball milling and sieving are specifically:

crushing the glass frit into small glass blocks with the particle size of less than 1 mm;

and ball-milling the small glass blocks, and sieving to obtain powder with the particle size of less than 10 microns.

In an optional embodiment, in the ball milling process, the small glass blocks are placed in a corundum ball milling tank for ball milling, the ball-material ratio is 5-10: 1, the ball milling rotation speed is 350-450 r/min, and the ball milling time is 30-90 min.

In an alternative embodiment, the milling balls are zirconia balls.

In a third aspect, an embodiment of the present invention provides a ceramic connection method, where a ceramic material is connected by using the above microcrystalline glass solder for ceramic connection or the microcrystalline glass solder for ceramic connection prepared by the above preparation method, and the connected ceramic material is a ceramic material using alumina as a base; preferably, the ceramic material is Al₂O₃At least one of ZTA and ARZ.

In an alternative embodiment, the method comprises the following steps:

uniformly mixing microcrystalline glass brazing filler metal and a binder, uniformly coating the mixture on a clean ceramic surface, and drying and forming to obtain a ceramic to-be-connected piece;

and carrying out brazing treatment on the ceramic to-be-connected piece in an air furnace, and cooling along with the furnace to obtain the ceramic after brazing connection.

In an alternative embodiment, the binder is at least one of water glass, epoxy adhesive, and polyurethane adhesive.

In an optional embodiment, the drying and forming temperature is 60-80 ℃.

In an alternative embodiment, the brazing treatment temperature is 1300-1350 ℃, and the holding time is 3-5 h.

The invention has the following beneficial effects:

because the microcrystalline glass solder has chemical compositions and specific phases with proper proportion, when the microcrystalline glass solder is used for high-temperature ceramic connection with alumina as a substrate, long and thin whiskers are generated through the reaction between the components in the solder and an oxide ceramic base material to realize stable and reliable connection of the base material, so that the strength of a ceramic connection part is improved, for example, the strength of Al connection₂O₃The highest strength of the connecting parts of oxide ceramics taking alumina as a matrix, such as ZTA, ARZ and the like, can reach 92.6 MPa; in addition, the residual stress of the joint part brazed by the microcrystalline glass brazing filler metal is small.

The preparation method provided by the application has the advantages of simple process, convenience in operation and no need of expensive equipment; the ceramic can be effectively connected in the air atmosphere without vacuum equipment, so that the cost is reduced, and the ceramic is suitable for industrial production.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is an XRD spectrum of an Al-B-O based microcrystalline glass solder prepared in examples 2 and 5 of the present invention;

FIG. 2 is an SEM image of the grain junction in the alumina porous ceramic material prepared by using the Al-B-O series glass-ceramic solder prepared in example 2 of the present invention;

FIG. 3 is an SEM image of the interface of an aluminum oxide sheet joint prepared by using the Al-B-O series glass-ceramic solder prepared in example 2 of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The following describes the microcrystalline glass solder for ceramic connection and the preparation method thereof and the ceramic connection method provided by the present application.

The microcrystalline glass solder for ceramic connection provided by the embodiment of the invention is a multi-phase mixture mainly composed of a glass phase and Al-B-O series oxide crystals, and the raw material components of the glass solder comprise the following components in percentage by mass: 35-45% of Al₂O₃、25～35％B₂O₃、15～25％SiO₂3-15% of alkaline earth metal oxide, 1-3% of alkali metal oxide and less than 2% of inevitable impurities, wherein the alkaline earth metal oxide comprises at least one of MgO and CaO, and the alkali metal oxide mainly comprises Na₂O and K₂At least one of O.

As far as the composition of the raw materials in the glass-ceramic solder is concerned, each oxide has its own role in the glass melt:

Al₂O₃and B₂O₃As the main component for forming Al-B-O. Al (Al)₂O₃The glass melt has reduced crystallization tendency and crystallization speed, and reduced expansion coefficient, and thus has raised heat stability, chemical stability and mechanical strength. B is₂O₃Meanwhile, the glass forms oxides, which not only can improve a series of performances of the glass, but also has good fluxing property.

SiO₂The glass is used as a main component for forming a glass phase and a common network former, is a glass framework, can effectively reduce the crystallization tendency of a glass melt, and improves the chemical stability and the thermal stability of the glass melt; but SiO in glass₂When the content is too high, the glass melting temperature will be increased, possibly causing devitrification.

The addition of alkaline earth metal oxides has a positive effect on the adjustment of the properties of the glass. CaO can accelerate the melting and clarification of glass and improve the chemical stability of the glass; however, CaO tends to crystallize the glass, lowers the viscosity of the glass melt at high temperatures, and excessively high CaO increases the brittleness of the glass. MgO can improve the chemical stability, mechanical strength and thermal stability of the glass and reduce the crystallization tendency of the glass; MgO at 1200 ℃ reduces the viscosity of the glass melt.

The alkali metal oxide is a fluxing agent for glass manufacture, typically Na₂O and K₂O。Na₂O lowers the viscosity of the glass melt, but excess Na₂O decreases the chemical stability, thermal stability and mechanical strength of the glass and increases the thermal expansion coefficient. K₂O can reduce the viscosity and the tendency of the glass melt to crystallize.

The microcrystalline glass solder for ceramic connection has chemical composition and specific phase in proper proportion, so that when the microcrystalline glass solder is used for high-temperature ceramic connection with alumina as a substrate, the wetting degree between the solder and a base metal is greatly improved through the reaction between components in the solder and the reaction between the components in the solder and an oxide ceramic base metal, long and thin whiskers are generated to realize stable and reliable connection of the base metal, and the strength of a ceramic connection part is improved, for example, the base metal is Al₂O₃The strength of the joint of oxide ceramics taking alumina as a matrix, such as ZTA and ARZ, can reach 92.6MPa at most, and the residual stress of the joint is small. In addition, within the content range of each component required by the application, the crystal content and the mechanical property of the microcrystalline glass solder can be controlled by adjusting the content of the alkali metal oxide and the alkaline earth metal oxide.

Further, the Al-B-O oxide crystal mainly includes Al₄B₂O₉、Al₁₈B₄O₃₃And Al₅BO₉。

The microcrystalline glass solder for ceramic connection provided by the embodiment of the invention is used for preparing the microcrystalline glass solder for ceramic connection provided by the embodiment of the invention, and comprises the following components:

mixing Al according to a predetermined mixture ratio₂O₃、B₂O₃、SiO₂And alkaline earth metal oxide, raising the temperature to 1200-1400 ℃ at the heating rate of 50-200 ℃/min, and preserving the temperature for 5-10 min to smelt into glass melt;

water quenching the glass melt to obtain a glass frit;

and drying, crushing, ball-milling and screening the glass frit to prepare the microcrystalline glass solder.

The temperature is rapidly increased at a heating rate of 50-200 ℃/min, so that the reaction of alumina and boron oxide caused by too slow temperature increase can be effectively avoided to generate Al-B-O series oxide. According to B₂O₃-Al₂O₃The binary phase diagram shows that when B is₂O₃Higher content (B)₂O₃> 25%), a 1 st liquid phase, corresponding to B, appears at around 450 ℃₂O₃Melting point of (2); between 600 and 800 ℃ and Al₂O₃And B₂O₃Form Al by reaction between₄B₂O₉And Al₁₈B₄O₃₃；Al₄B₂O₉Stable at more than 1100 deg.C, Al₁₈B₄O₃₃The stability is achieved at the temperature of more than 1900 ℃. Because B₂O₃Has a low melting point, and if the temperature rise rate is too slow, B is₂O₃The burning loss is serious in the process of heating and smelting the glass melt; in the system, the mixing and dissolving temperature of various raw materials is about 1150-1350 ℃ (related to the mixture ratio of the raw materials), so that Al is inevitably generated by the system in the process of preparing glass melt by smelting (in the temperature rising stage and the heat preservation stage)₄B₂O₉And Al₁₈B₄O₃₃(ii) a In order to ensure the content of glass phase in the finally prepared microcrystalline glass solder and reduce Al₄B₂O₉And Al₁₈B₄O₃₃When Al-B-O series oxides are generated in large quantity, the aim can be achieved by adopting a rapid smelting process. According to the mixing and dissolving temperature of the raw materials in the application, the smelting temperature can be selected to be 1200-1400 ℃, the heat preservation time is suitable under 5-10 min, and if the smelting temperature is too high and the heat preservation time is too long, Al in the product is₄B₂O₉And Al₁₈B₄O₃₃An excessive content of the precipitated phase (see FIG. 1) causes a decrease in the joining strength.

The preparation process is simple and convenient to operate, and expensive equipment is not needed; the ceramic can be effectively connected in the air atmosphere without vacuum equipment, so that the cost is reduced, and the ceramic is suitable for industrial production.

The preparation method specifically comprises the following steps:

and S1, smelting to prepare glass melt.

Weighing Al according to the requirements of each chemical component in the microcrystalline glass solder₂O₃、B₂O₃、SiO₂And alkaline earth metal oxide.

And (3) placing the raw materials in a three-dimensional motion mixer, and mixing for 2-5 h to uniformly mix all the components.

And (3) placing the uniformly mixed ceramic powder raw material into a graphite crucible of an induction heating furnace, raising the temperature to 1200-1400 ℃ at a heating rate of 50-200 ℃/min, rapidly smelting the ceramic powder raw material into a glass melt, uniformly stirring the molten melt, and keeping the temperature for 5-10 min to prepare the glass melt.

S2, water quenching

And quickly pouring the smelted glass melt into cold water for water quenching treatment, and drying for 1-2 hours at 100-120 ℃ after water filtration to obtain the glass frit.

S3, preparing powder

And (3) crushing the glass frits into small glass blocks with the particle size of less than 1mm by using a Raymond mill.

And (3) placing the small glass blocks into a corundum grinding tank for ball grinding, wherein the ball-material ratio is 5-10: 1, the ball grinding speed is 350-450 r/min, and the ball grinding time is 30-90 min so as to ensure full grinding. Furthermore, zirconia balls are selected as grinding balls during ball milling.

And finally, screening, namely placing the powder subjected to ball milling into a vibrating screen to obtain the microcrystalline glass solder with the particle size of less than 10 microns.

The embodiment of the invention also provides a ceramic connecting method, and the microcrystalline glass solder for ceramic connection provided by the embodiment of the invention is adopted to connect ceramic materials and is connectedThe connected ceramic material is a ceramic material taking alumina as a matrix; preferably, the ceramic material is Al₂O₃At least one of ZTA and ARZ.

The ceramic connection method specifically comprises the following steps:

1. uniformly mixing the microcrystalline glass brazing filler metal and a binder, uniformly coating the mixture on a clean ceramic surface, and drying and forming to obtain a ceramic to-be-connected piece;

2. and carrying out brazing treatment on the ceramic to-be-connected piece in an air furnace, and cooling along with the furnace to obtain the brazed and connected ceramic, wherein the binder is at least one of water glass, epoxy adhesive, polyurethane adhesive and the like.

Preferably, the drying and forming temperature is 60-80 ℃.

Preferably, the brazing treatment temperature is 1300-1350 ℃ (for example: 1300 ℃, 1320 ℃ or 1350 ℃) and the holding time is 3-5 h (for example, 3h, 4h or 5 h).

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

This example provides an Al-B-O based glass-ceramic solder for ceramic connection, which comprises Al in terms of weight percentage₂O₃：35％，B₂O₃：35％，SiO₂: 15%, MgO: 10%, CaO: 3% of Na and the balance of₂O：1％，K₂O：1％。

S1, weighing Al according to the mixture ratio₂O₃、B₂O₃、SiO₂Mixing the MgO and CaO ceramic powder raw materials in a three-dimensional motion mixer for 5 hours to uniformly mix all the components;

s2, placing the ceramic powder raw material uniformly mixed in the step S1 in a graphite crucible of a heating electric furnace, heating to 1350 ℃ at the speed of 100 ℃/min, rapidly smelting the ceramic powder raw material into a glass melt, uniformly stirring the molten melt, and keeping the temperature for 10 min;

s3, quickly pouring the glass melt smelted in the step S2 into cold water for water quenching treatment, and drying at 100 ℃ for 2 hours after water filtration to prepare glass frit;

s4, crushing the glass frit in the step S3 to be less than 1mm, then placing the glass frit in a ball mill to ball mill for 90min at the rotating speed of 450r/min, and finally screening by a vibrating screen to obtain powder with the particle size of less than 10 microns, so that the required microcrystalline glass solder is obtained.

Example 2

This example provides an Al-B-O based glass-ceramic solder for ceramic connection, which comprises Al in terms of weight percentage₂O₃：40％，B₂O₃：30％，SiO₂: 15%, MgO: 10%, CaO: 3% and the balance unavoidable impurities, the impurities being mainly about Na₂O：1％，K₂O：1％。

S1, weighing Al according to the mixture ratio₂O₃、B₂O₃、SiO₂Mixing the MgO and CaO ceramic powder raw materials in a three-dimensional motion mixer for 5 hours to uniformly mix all the components;

s2, placing the ceramic powder raw material uniformly mixed in the step S1 in a graphite crucible of a heating electric furnace, heating to 1350 ℃ at the speed of 100 ℃/min, rapidly smelting the ceramic powder raw material into a glass melt, uniformly stirring the molten melt, and keeping the temperature for 10 min;

s3, quickly pouring the glass melt smelted in the step S2 into cold water for water quenching treatment, and drying at 100 ℃ for 2 hours after water filtration to prepare glass frit;

s4, crushing the glass frit in the step S3 to be less than 1mm, then placing the glass frit in a ball mill to ball mill for 90min at the rotating speed of 450r/min, and finally screening by a vibrating screen to obtain powder with the particle size of less than 10 microns, so that the required microcrystalline glass solder is obtained.

Example 3

This example provides an Al-B-O based glass-ceramic solder for ceramic connection, which comprises Al in terms of weight percentage₂O₃：45％，B₂O₃：25％，SiO₂: 15%, MgO: 10%, CaO: 3% of Na and the balance of₂O：1％，K₂O：1％。

S1、Weighing Al according to the above mixture ratio₂O₃、B₂O₃、SiO₂Mixing the MgO and CaO ceramic powder raw materials in a three-dimensional motion mixer for 5 hours to uniformly mix all the components;

s2, placing the ceramic powder raw material uniformly mixed in the step S1 in a graphite crucible of a heating electric furnace, heating to 1350 ℃ at the speed of 100 ℃/min, rapidly smelting the ceramic powder raw material into a glass melt, uniformly stirring the molten melt, and keeping the temperature for 10 min;

s3, quickly pouring the glass melt smelted in the step S2 into cold water for water quenching treatment, and drying at 100 ℃ for 2 hours after water filtration to prepare glass frit;

s4, crushing the glass frit in the step S3 to be less than 1mm, then placing the glass frit in a ball mill to ball mill for 90min at the rotating speed of 450r/min, and finally screening by a vibrating screen to obtain powder with the particle size of less than 10 microns, so that the required microcrystalline glass solder is obtained.

Example 4

This example is substantially the same as example 2 except that the melting temperature at the time of preparing the glass filler metal was 1300 ℃.

Example 5

This example is substantially the same as example 2 except that the melting temperature at the time of preparing the glass filler metal was 1400 ℃.

Example 6

This example is substantially the same as example 2 except that the composition of the raw materials for preparing the glass filler metal is different: al in this example₂O₃：40％，B₂O₃：30％，SiO₂: 20%, MgO: 5%, CaO: 3% of Na and the balance of₂O：1％，K₂O：1％。

Example 7

This example is substantially the same as example 2 except that the composition of the raw materials for preparing the glass filler metal is different: al in this example₂O₃：40％，B₂O₃：30％，SiO₂: 25%, CaO: 3% of Na and the balance of₂O：1％，K₂O：1％。

Example 8

This example is substantially the same as example 2 except that the composition of the raw materials for preparing the glass filler metal is different: al in this example₂O₃：40％，B₂O₃：30％，SiO₂: 15%, MgO: 7%, CaO: 6% and the balance being about Na₂O：1％，K₂O：1％。

Example 9

This example is substantially the same as example 2 except that the composition of the raw materials for preparing the glass filler metal is different: al in this example₂O₃：40％，B₂O₃：30％，SiO₂: 15%, MgO: 6%, CaO: 7% of Na and the balance of₂O：1％，K₂O：1％。

Example 10

This embodiment is substantially the same as embodiment 2 except that: the heating rate was 50 ℃/min.

Example 11

This embodiment is substantially the same as embodiment 2 except that: the heating rate was 150 ℃/min.

Examples 1, 2 and 3 Al alone₂O₃And B₂O₃The specific gravities of (1) were different, the melting temperatures used for preparing only glass solders in examples 2, 4 and 5 were different, and only SiO was used in examples 2, 6 and 7₂Examples 2, 8 and 9 differ only in the specific gravities of MgO and CaO, and examples 2, 10 and 11 differ only in the temperature rise rate.

Comparative example 1

This comparative example does not include the alkaline earth metal oxide as a chemical component with respect to example 1, and the relationship of the proportions of the remaining components is the same as in example 1. The preparation method is the same as that of example 1.

Comparative example 2

This comparative example does not include the alkaline earth metal oxide as a chemical component with respect to example 2, and the relationship of the proportions of the remaining components is the same as in example 2. The preparation method is the same as that of example 2.

Comparative example 3

This comparative example does not include the alkaline earth metal oxide as a chemical component with respect to example 3, and the relationship of the proportions of the remaining components is the same as in example 3. The preparation method is the same as in example 3.

Comparative example 4

This comparative example is substantially the same as example 2 except that the temperature rise rate of this comparative example is 10 ℃/min.

Comparative example 5

The comparative example is substantially the same as example 2 except that the comparative example spreads the microcrystalline glass solder on the surface of the ceramic material by screen printing without using a binder when the ceramic material is joined.

Examples of the experiments

The microcrystalline glass solders prepared in examples 1 to 10 and comparative examples 1 to 5 were bonded to alumina ceramic particles and alumina flakes, and were tested for compressive strength and shear strength, respectively (see table 1 for test results, and temperatures shown in table 1 are brazing temperatures).

TABLE 1 Properties of microcrystalline brazing filler metal for Al-B-O glass for bonding alumina

Ps: the porous ceramic could not be prepared by the method of comparative example 5

As can be seen from the table above, the compressive strength and the shear strength of the alumina porous material prepared by using the microcrystalline glass solder provided by the embodiment of the application are higher than those of the comparative example. Comparing the bonding effects of the glass solders prepared in examples 1, 2 and 3 of Table 1, it can be found that by adjusting Al₂O₃And B₂O₃The specific gravity of the Al-B-O series glass brazing filler metal is that the prepared Al-B-O series glass brazing filler metal can meet high-strength connection under different high-temperature conditions; only from the connection effect of the Al-B-O series microcrystalline glass solder prepared in the comparative examples 2 and 5 in the Table 1, the connection effect of the glass frit prepared by melting at 1350 ℃ selected in the example 2 is relatively good, while the strength of the ceramic material is slightly lower than that of the glass frit prepared by melting at a high temperature (1400 ℃) in the example 5 under different connection temperatures, mainly because the strength of the ceramic material is slightly lower than that of the glass frit prepared by melting at a high temperature (1400 ℃), the connection effect is relatively goodOn the premise of adopting the raw materials of the components, the melting temperature is increased, the reaction among oxide components in the glass melt is intensified, and Al in the product is generated₁₈B₄O₃₃、MgAl₂O₄The content of the precipitated phase (shown in figure 1) is increased, so that the content of the glass phase and the oxide in the glass brazing filler metal is reduced, and the subsequent reaction with the surface of the alumina ceramic is weak, so that the fact that the reaction between oxide components in the glass melt is too violent when the melting temperature exceeds the range required by the application can be inferred, and the Al in the product is caused₁₈B₄O₃₃、MgAl₂O₄When the precipitated phases are too much, the bonding strength of the joint after the oxide ceramics are connected is low, and the requirements are difficult to meet; as can be seen from comparative examples 2, 6 and 7, SiO is within the range required by the present application₂The specific gravity of the MgO is increased, so that the connection strength of the ceramic material at higher temperature can be effectively improved; it is understood from comparative examples 2, 8 and 9 that the specific gravities of MgO and CaO increase, and the influence on the bonding strength at a lower temperature (1100 ℃ C.) is significant, and the difference gradually disappears as the bonding temperature increases. Comparing the test results of example 1 and comparative example 1, example 2 and comparative example 2, example 3 and comparative example 3, it can be seen that the solder prepared in the examples (containing alkaline earth metal oxide in the raw material components) has higher bonding strength in application than the corresponding comparative examples, indicating that the chemical components of the raw materials should be within the range required in the present application, and if not within the required range, the bonding strength will be reduced; in comparison with examples 2, 10 and 11, it can be found that when the temperature rise rate is within the range of the present application, the bonding strength difference of the joint after the obtained glass solder is connected with the ceramic material is not large; compared with the examples 2, 10 and 11, the temperature rise rate of the comparative example 4 is much lower (the temperature rise rate for preparing silicate glass is selected), and the bonding strength of the joint of the obtained glass solder and the ceramic material is obviously lower, which indicates that the temperature rise rate of the glass solder during smelting is within the range required by the application.

The SEM appearance of the joint of particles in the glass solder-connected alumina porous ceramic material prepared in the example 2 is shown in figure 2, and the SEM appearance of the joint of the glass solder-connected alumina sheet prepared in the example 2 is shown in figure 3. As can be seen from FIGS. 2 and 3, the Al-B-O glass-ceramic brazing filler metal prepared by the method can realize stable connection of ceramic materials.

In conclusion, the microcrystalline glass solder provided by the invention has the chemical composition and the specific phase with proper proportion, so that when the microcrystalline glass solder is used for high-temperature ceramic connection, the wetting degree between the solder and a parent metal is greatly improved through the reaction between the components in the solder and an oxide ceramic parent metal, long and thin whiskers are generated to realize stable and reliable connection of the parent metal, the strength of a ceramic connection part is improved, and particularly, the parent metal is Al₂O₃Alumina-based ceramic materials such as ZTA and ARZ.

The preparation method of the microcrystalline glass solder provided by the invention has the advantages of simple preparation process, convenience in operation and no need of expensive equipment; the ceramic can be effectively connected in the air atmosphere without vacuum equipment, so that the cost is reduced, and the ceramic is suitable for industrial production.

According to the ceramic connecting method provided by the invention, the microcrystalline glass solder for ceramic connection is used for connecting ceramic materials, so that the connecting strength is high.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.