CN116835994A - Low-temperature connection method of alumina ceramic and 1060 pure aluminum - Google Patents

Abstract

The invention provides a low-temperature _{connection method between alumina ceramics and 1060 pure aluminum. Bi2O3 , B2O3 ,} ZnO, MgO and _TiO2 are used as raw materials to prepare bismuthate glass powder, and then bismuthate glass powder is used as raw materials. The glass solder paste made of glass powder and organic carrier is used as solder. The alumina ceramics and 1060 pure aluminum are formed into joints to be welded. The soldering process is carried out at a temperature of 420 to 500°C to achieve the bonding between alumina ceramics and 1060 pure aluminum. Reliable connection at low temperature; compared with the existing technology, the bismuthate glass powder of the present invention has a lower glass transition temperature, glass softening temperature and thermal expansion coefficient, reduces its welding temperature with pure aluminum, and realizes alumina ceramics It is connected to 1060 pure aluminum at low temperature, and its thermal expansion coefficient is closer to that of alumina ceramics, which reduces the residual stress of the weld and improves the strength of the joint; the invention has simple process, low cost, small deformation, green and environmental protection, and is a heterogeneous Material welding technology field.

Description

A low-temperature connection method between alumina ceramics and 1060 pure aluminum

Technical field

The invention relates to the technical field of dissimilar material welding, and in particular to a low-temperature connection method between alumina ceramics and 1060 pure aluminum.

Background technique

Alumina ceramics have the advantages of high hardness, excellent wear resistance and corrosion resistance, making them one of the most widely used industrial ceramics. As a widely used metal material after steel, pure aluminum has the advantages of light weight, high electrical conductivity and high thermal conductivity. At present, the connectors between alumina ceramics and pure aluminum or aluminum alloys have been widely used in fields such as electronic devices, automobile packaging, and lightweight parts manufacturing. For example, ceramic pistons and ceramic tappets in all-aluminum automobile engines are alumina ceramics. Connectors with aluminum alloys, therefore, it is of great significance to study the connection technology between alumina ceramics and pure aluminum or aluminum alloys.

Previous research has shown that when connecting ceramics and pure aluminum, it is necessary to pre-metallize the ceramic surface to form a metal film, and then use the metal film as a solder to connect the two through soldering to form a reliable joint. . However, the aluminum surface easily forms a dense aluminum oxide film, which will hinder the wetting of the solder on the aluminum surface, thus reducing the welding efficiency and welding quality; in addition, due to the low melting point of aluminum, which is only 660°C, traditional The active metal brazing method requires a high welding temperature and is not suitable for the connection between the two. Furthermore, the thermal expansion coefficients of alumina ceramics and pure aluminum are about three times different, which can easily lead to large residues at the weld interface. Stress affects the strength of the joint. Based on this, there is an urgent need to study a suitable connection method between alumina ceramics and pure aluminum.

Contents of the invention

In order to solve the above technical problems, the technical solution adopted in this application is to provide a low-temperature connection method between alumina ceramics and 1060 pure aluminum to solve the problems of low welding efficiency and poor welding quality in the existing connection methods of ceramics and pure aluminum. Technical problems include poor performance, higher welding temperature, and lower joint strength.

The embodiment of the present application provides a low-temperature connection method between alumina ceramics and 1060 pure aluminum, which includes the following steps:

(1) Mix Bi ₂ O ₃ , B ₂ O ₃ , ZnO, MgO and TiO ₂ powders evenly, and obtain bismuth acid salt glass powder after heating and insulation, water quenching and grinding;

(2) The surface to be welded of 1060 pure aluminum is polished, cleaned, dried, and then heated and insulated for pre-oxidation treatment;

(3) Mechanically grind, polish, clean and dry the surface to be welded of alumina ceramics;

(4) Mix bismuthate glass powder and organic carrier evenly to make glass solder paste, and evenly apply it on the surfaces to be welded of alumina ceramics and 1060 pure aluminum, and then place them in opposite contact to obtain the connector to be welded;

(5) Heat the joint to be welded to the welding temperature, perform heat preservation treatment, and then cool it to finally obtain an alumina ceramic-1060 pure aluminum welded joint.

Preferably, in step (1), the bismuthate glass powder includes the following mass percentage components: the content of Bi ₂ O ₃ is 50 to 60%, the content of B ₂ O ₃ is 30 to 35%, and the content of ZnO is 30 to 35%. The content is 5 to 10%, the content of MgO is 1 to 5%, and the content of TiO ₂ is 1 to 5%.

Preferably, in step (1), heat to 1150-1200°C and keep warm for 60 minutes.

Preferably, in step (1), after grinding, the powder is sieved with 300 mesh to obtain bismuthate glass powder with a diameter of 46 to 50 μm.

Preferably, in step (2), the cleaning method is ultrasonic vibration cleaning. 1060 pure aluminum is sequentially placed in acetone solution and absolute ethanol for ultrasonic vibration cleaning. The cleaning time is 10 to 15 minutes.

Preferably, in step (2), the mixture is heated to 400-550°C at a heating rate of 10°C/min and maintained for 1-4 hours.

Preferably, in step (3), the surface roughness of the surface to be welded of the alumina ceramic is polished to 0.08-0.10 μm; the cleaning method is ultrasonic vibration cleaning, and the alumina ceramic is sequentially placed in an acetone solution and absolute ethanol. Ultrasonic vibration cleaning, cleaning time is 10 to 15 minutes.

Preferably, in step (4), the organic carrier is mixed with terpineol, ethyl cellulose, ethyl acetate, 1-2 propylene glycol, and soybean lecithin in a mass ratio of 65:5:15:7.5:7.5 , the mass ratio of the bismuthate glass powder to the organic carrier is 7.5:1.

Preferably, in step (4), the coating thickness of the glass solder paste is 90-120 μm.

Preferably, in step (5), the joints to be welded are preheated before welding, heated to 250°C at a heating rate of 5 to 8°C/min, and kept for 10 to 60 minutes; Heating to 420~500℃ at a high heating rate, and holding at the welding temperature for 10~40min.

The invention provides a low-temperature _{connection method between alumina ceramics and 1060 pure aluminum. Bi2O3 , B2O3 ,} ZnO, MgO and _TiO2 are used as raw materials to prepare bismuthate glass powder, and then bismuthate glass powder is used as raw materials. The glass solder paste made of glass powder and organic carrier is used as solder. The alumina ceramics and 1060 pure aluminum are formed into joints to be welded. The soldering process is carried out at a temperature of 420 to 500°C to achieve the bonding between alumina ceramics and 1060 pure aluminum. Reliable connection at low temperature;

Compared with the prior art, the beneficial effects of the present invention are:

(1) The bismuthate glass powder of the present invention has a low glass transition temperature (T _g =320°C), glass softening temperature (T _f =355°C) and thermal expansion coefficient (7.5～10×10 ^-6 K ^{- 1} ), lowering the welding temperature with pure aluminum, achieving low-temperature connection between alumina ceramics and 1060 pure aluminum, and at the same time, its thermal expansion coefficient is closer to that of alumina ceramics, reducing the residual stress of the weld and improving the joint strength strength;

(2) The bismuthate glass powder of the present invention adds two raw materials, MgO and TiO _2. The titanium in TiO ₂ exists in the form of Ti ⁴⁺ in the glass network, which increases the packing density of oxygen atoms in the glass and improves It improves the tightness of the glass network structure, thereby improving the thermal stability of the glass; the presence of MgO can improve the chemical stability and mechanical strength of the glass, and can reduce the crystallization tendency of the glass and prevent the glass from becoming brittle due to crystallization; MgO and The addition of TiO ₂ improves the strength of the joint and achieves a reliable connection between alumina ceramics and 1060 pure aluminum;

(3) By pre-oxidizing 1060 pure aluminum, the present invention improves the wetting of the solder material on the aluminum surface, solves the technical problem of the adverse impact of the oxide film on the metal surface on the brazing process, and improves the performance of the soldering process between 1060 pure aluminum and glass. The sealing of the material sealing process improves the welding efficiency and welding quality;

(4) In the present invention, by preheating the joints to be welded, the organic carrier can be fully volatilized, avoiding the generation of pores in the welded joints, and improving the quality and strength of the joints;

(5) The process of the present invention is simple, low in cost, small in deformation, and environmentally friendly. The room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint is 14 to 24 MPa. The brazed joint has a dense structure, ensuring that the alumina ceramic and 1060 pure aluminum welded joints are Reliability of aluminum connections.

Description of the drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the purpose of the present application. For some embodiments, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a microstructure diagram of the alumina ceramic-1060 pure aluminum welded joint in Example 10 of the present application;

Figure 2 is a microstructure diagram of the alumina ceramic-1060 pure aluminum welded joint in Comparative Example 1 of the present application.

Explanation of symbols in the figure:

1. Alumina ceramic; 2.1060 pure aluminum.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clear, this application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application. The raw materials and devices used in the present invention, unless otherwise specified, are all conventional commercially available products; the methods used, unless otherwise specified, are conventional methods.

Example 1

This embodiment provides a low-temperature connection method between alumina ceramics and 1060 pure aluminum, which includes the following steps:

(1) Weigh 50% Bi ₂ O ₃ , 35% B ₂ O ₃ , 5% ZnO, 5% MgO and 5% TiO ₂ powder respectively according to mass percentage, and mix them evenly in a drum ball mill, and then mix The final powder is placed in a muffle furnace, heated to 1150~1200°C and kept for 60 minutes to obtain molten glass. The molten glass is quenched with water to obtain glass particles. The glass particles are ground and sieved through 300 mesh to obtain Bismuthate glass powder with a diameter of 46 to 50 μm;

(2) Use sandpaper to polish the surface to be welded of 1060 pure aluminum, and then place the 1060 pure aluminum in an acetone solution and absolute ethanol for ultrasonic vibration cleaning. The cleaning time is 10 to 15 minutes. After cleaning, remove the 1060 pure aluminum. Dry it, then place it in a muffle furnace, heat it to 400°C at a heating rate of 10°C/min, keep it for 1 hour to pre-oxidize, and then cool it in the furnace;

(3) Use a diamond sand table to mechanically grind the surface of the alumina ceramic to be welded, and polish it until the surface roughness of the surface to be welded is 0.08-0.10 μm, and then place the alumina ceramic in an acetone solution and anhydrous solution in sequence. Carry out ultrasonic vibration cleaning in ethanol, the cleaning time is 10 to 15 minutes, and dry the alumina ceramics after cleaning;

(4) Mix terpineol, ethyl cellulose, ethyl acetate, 1-2 propylene glycol, and soy lecithin according to the mass ratio of 65:5:15:7.5:7.5 to obtain an organic carrier, and then add bismuth acid salt glass The powder and organic carrier are mixed according to the mass ratio of 7.5:1, and placed in a planetary gravity mixer to mix evenly to form a glass solder paste. The glass solder paste is evenly applied on the surfaces to be welded of alumina ceramics and 1060 pure aluminum. The coating thickness is 90-120 μm, and then the alumina ceramics and 1060 pure aluminum are placed in opposing contact to obtain the connector to be welded;

(5) Place the joints to be welded in the muffle furnace, preheat the joints to be welded first, heat to 250°C at a heating rate of 5 to 8°C/min, keep the heat for 30 minutes, and then weld the welded parts. Heating to 420°C at a heating rate of 5 to 8°C/min, holding for 10 minutes, and then cooling in the furnace, finally obtaining an alumina ceramic-1060 pure aluminum welded joint.

The mechanical properties of the alumina ceramic-1060 pure aluminum welded joint in Example 1 were tested, and the measured room temperature shear strength is shown in Table 1.

Example 2

The difference between this implementation method and Example 1 is that in step (1), 55% Bi ₂ O ₃ , 32% B ₂ O ₃ , 7% ZnO, 3% MgO and 3% TiO ₂ powders are weighed according to mass percentages. , other steps are the same, and the alumina ceramic-1060 pure aluminum welded joint is finally obtained. The measured room temperature shear strength is shown in Table 1.

Example 3

The difference between this implementation method and Example 1 is that in step (1), 60% Bi ₂ O ₃ , 30% B ₂ O ₃ , 8% ZnO, 1% MgO and 1% TiO ₂ powder are respectively weighed according to mass percentages. , other steps are the same, and the alumina ceramic-1060 pure aluminum welded joint is finally obtained. The measured room temperature shear strength is shown in Table 1.

Table 1 Process parameters and room temperature shear strength of the welded joints of Examples 1 to 3

Please refer to Table 1. When the content of each raw material in the bismuthate glass powder is different, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint also changes accordingly. The higher the value of Bi ₂ O ₃ /B ₂ O ₃ The higher the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint.

Example 4

The difference between this implementation method and Example 3 is that in step (2), the heating rate is 10°C/min to 480°C. The other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained, and its room temperature is measured. The shear strength is shown in Table 2.

Example 5

The difference between this implementation method and Example 3 is that in step (2), it is heated to 550°C at a heating rate of 10°C/min. The other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained, and its room temperature is measured. The shear strength is shown in Table 2.

Table 2 Process parameters and room temperature shear strength of the welded joints of Examples 3 to 5

Please refer to Table 2. As the temperature increases during the pre-oxidation treatment, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint gradually increases. When the temperature is 550°C, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint increases. The room temperature shear strength of the joint is the highest, reaching 16.43MPa; therefore, the temperature during the pre-oxidation treatment is preferably 550°C.

Example 6

The difference between this implementation method and Example 5 is that in step (2), it is pre-oxidized by holding it for 2.5 hours. The other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained, and its room temperature shear strength is measured. as shown in Table 3.

Example 7

The difference between this implementation method and Example 5 is that in step (2), it is pre-oxidized by holding it for 4 hours, and the other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained, and its room temperature shear strength is measured as follows As shown in Table 3.

Table 3 Process parameters and room temperature shear strength of the welded joints of Examples 5 to 7

Please refer to Table 3. As the holding time increases during the pre-oxidation treatment, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint increases first and then becomes stable. When the holding time is 2.5h, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint increases. -1060 pure aluminum welded joints have the highest room temperature shear strength, reaching 17.36MPa; therefore, the holding time during the pre-oxidation process is preferably 2.5h.

Example 8

The difference between this implementation method and Example 6 is that in step (5), the welding temperature is 460°C, and other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained, and its room temperature shear strength is measured as shown in Table 4. Show.

Example 9

The difference between this implementation method and Example 6 is that in step (5), the welding temperature is 500°C, and other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained, and its room temperature shear strength is measured as shown in Table 4. Show.

Table 4 Process parameters and room temperature shear strength of the welded joints of Examples 6, 8-9

Please refer to Table 4. As the temperature increases during the welding process, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint first increases and then decreases. When the temperature is 460°C, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint The room temperature shear strength of the joint is the highest, reaching 19.28MPa; therefore, the temperature during the welding process is preferably 460°C.

Example 10

The difference between this implementation method and Example 8 is that in step (5), the temperature is maintained for 30 minutes during the welding process. The other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained. The room temperature shear strength is measured as shown in Table 5. Show.

Example 11

The difference between this implementation method and Example 8 is that in step (5), the temperature is maintained for 40 minutes during the welding process. The other steps are the same. Finally, an alumina ceramic-1060 pure aluminum welded joint is obtained. The measured room temperature shear strength is as shown in Table 5. Show.

Table 5 Process parameters and room temperature shear strength of the welded joints of Examples 8, 10-11

Please refer to Table 5. As the holding time increases during the welding process, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint first increases and then decreases. When the holding time is 30 minutes, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint increases. The room temperature shear strength of the welded joint is the highest, reaching 23.39MPa; therefore, the holding time during the welding process is preferably 30 minutes.

In summary, the optimal conditions for the brazing process of alumina ceramics and 1060 pure aluminum are: the temperature during the pre-oxidation treatment is 550°C, the holding time is 2.5h, and the temperature during the preheating treatment is 250°C. The holding time is 30 minutes, the temperature during the welding process is 460°C, and the holding time is 30 minutes; the alumina ceramic-1060 pure aluminum welded joint of Example 10 is microscopically observed through a scanning electron microscope (SEM), and the microstructure diagram is obtained as follows: As shown in Figure 1, it can be seen from Figure 1 that the alumina ceramic-1060 pure aluminum welded joint has a dense structure, no unwelded areas, and no cracks.

Comparative example 1

The difference between this implementation method and Example 10 is that in step (2), after drying the 1060 pure aluminum, no pre-oxidation treatment is performed. The other steps are the same, and finally an alumina ceramic-1060 pure aluminum welded joint is obtained. The microscopic The tissue diagram is shown in Figure 2, and the measured room temperature shear strength is shown in Table 6.

Table 6 Process parameters and room temperature shear strength of the welded joints of Example 10 and Comparative Example 1

Please refer to Table 6. When the 1060 pure aluminum is not pre-oxidized, the room temperature shear strength of the obtained alumina ceramic-1060 pure aluminum welded joint is significantly reduced; please refer to Figure 2, the alumina ceramic-1060 pure aluminum in Comparative Example 1 There are obvious cracks in the aluminum welded joints. It can be seen that the pre-oxidation treatment on the surface of 1060 pure aluminum can help improve the sealing performance of the sealing process with the glass solder and solve the problem of the oxide film on the metal surface that is detrimental to the brazing process. affect the technical issues, thereby improving the quality of the weld and improving the room temperature shear strength of the joint.

The invention provides a low-temperature _{connection method between alumina ceramics and 1060 pure aluminum. Bi2O3 , B2O3 ,} ZnO, MgO and _TiO2 are used as raw materials to prepare bismuthate glass powder, and then bismuthate glass powder is used as raw materials. The glass solder paste made of glass powder and organic carrier is used as solder. The alumina ceramics and 1060 pure aluminum are formed into joints to be welded. The soldering process is carried out at a temperature of 420 to 500°C to achieve the bonding between alumina ceramics and 1060 pure aluminum. Reliable connection at low temperature;

Compared with the prior art, (1) the bismuthate glass powder of the present invention has a lower glass transition temperature (T _g =320°C), glass softening temperature (T _f =355°C) and thermal expansion coefficient (7.5~ 10×10 ^-6 K ^-1 ), which reduces the welding temperature with pure aluminum and realizes the low-temperature connection between alumina ceramics and 1060 pure aluminum. At the same time, its thermal expansion coefficient is closer to that of alumina ceramics, reducing the welding seam. Residual stress improves the strength of the joint; (2) The bismuthate glass powder of the present invention adds two raw materials: MgO and TiO _2. The titanium in TiO ₂ exists in the form of Ti ⁴⁺ in the glass network, increasing the The packing density of oxygen atoms in the glass improves the tightness of the glass network structure, thereby improving the thermal stability of the glass; the presence of MgO can improve the chemical stability and mechanical strength of the glass, and can reduce the crystallization tendency of the glass and prevent the glass from crystallizing. It becomes brittle due to crystallization; the addition of MgO and TiO ₂ improves the strength of the joint and realizes a reliable connection between alumina ceramics and 1060 pure aluminum; (3) The present invention improves the brazing efficiency by pre-oxidizing 1060 pure aluminum. The wetting of the material on the aluminum surface solves the technical problem of the negative impact of the oxide film on the metal surface on the brazing process, and improves the sealing performance of the sealing process between 1060 pure aluminum and glass brazing material, thus improving the welding efficiency and welding quality; (4) In the present invention, by preheating the joints to be welded, the organic carrier can be fully volatilized, avoiding the generation of pores in the welded joints, and improving the quality and strength of the joints; (5) The present invention has simple process, low cost, small deformation, Green and environmentally friendly, the room temperature shear strength of the alumina ceramic-1060 pure aluminum welded joint is 14-24MPa, and the brazed joint has a dense structure, ensuring the reliability of the connection between alumina ceramics and 1060 pure aluminum; it can be widely used in dissimilar material welding technology field.

It should be noted that in the above embodiment, the holding time during the preheating process is set to 30 minutes. This is only a preferred embodiment. In actual production, the holding time during the preheating process can be set to 10 to 60 minutes. Just within the range.

The above-described embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still implement the above-mentioned implementations. The technical solutions described in the examples are modified, or some of the technical features are equivalently replaced; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions in the embodiments of this application, and should be included in within the protection scope of this application.

Claims (10)

1. A low temperature joining method of alumina ceramic and 1060 pure aluminum, comprising the steps of:

(1) Bi is mixed with ₂ O ₃ 、B ₂ O ₃ ZnO, mgO and TiO ₂ Uniformly mixing the powder, heating, preserving heat, quenching with water, and grinding to obtain bismuthate glass powder;

(2) Polishing, cleaning and drying the surface to be welded of 1060 pure aluminum, and then heating and preserving heat to perform pre-oxidation treatment;

(3) Mechanically polishing, cleaning and drying the surface to be welded of the alumina ceramic;

(4) Uniformly mixing bismuthate glass powder and an organic carrier to prepare glass soldering paste, uniformly coating the glass soldering paste on a surface to be soldered of alumina ceramics and 1060 pure aluminum, and then placing the glass soldering paste in opposite contact to obtain a connecting piece to be soldered;

(5) And heating the to-be-welded connecting piece to the welding temperature, carrying out heat preservation treatment, and then cooling to finally obtain the alumina ceramic-1060 pure aluminum welding joint.

2. The method for low temperature joining of alumina ceramic and 1060 pure aluminum of claim 1, wherein in step (1), the bismuthate glass frit comprises the following components in mass percent: bi (Bi) ₂ O ₃ The content of (B) is 50-60 percent ₂ O ₃ 30-35%, znO 5-10%, mgO 1-5%, tiO ₂ The content of (2) is 1-5%.

3. The method for low temperature joining of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in step (1), the temperature is maintained for 60min by heating to 1150-1200 ℃.

4. The method for low-temperature joining of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (1), a bismuthate glass powder having a diameter of 46 to 50 μm is obtained by sieving with 300 mesh sieve after grinding.

5. The method for low-temperature connection of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (2), the cleaning mode is ultrasonic vibration cleaning, and 1060 pure aluminum is sequentially placed in acetone solution and absolute ethyl alcohol to be subjected to ultrasonic vibration cleaning, wherein the cleaning time is 10-15 min.

6. The method for low temperature joining of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (2), the alumina ceramic is heated to 400 to 550 ℃ at a heating rate of 10 ℃/min, and the temperature is maintained for 1 to 4 hours.

7. The method for low-temperature joining of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (3), the surface roughness of the surface to be welded of the alumina ceramic is polished to 0.08-0.10 μm; the cleaning mode is ultrasonic vibration cleaning, the alumina ceramics are sequentially placed in acetone solution and absolute ethyl alcohol for ultrasonic vibration cleaning, and the cleaning time is 10-15 min.

8. The method for low-temperature connection of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (4), the organic carrier is formed by mixing terpineol, ethyl cellulose, ethyl acetate, 1-2 propylene glycol and soybean lecithin according to a mass ratio of 65:5:15:7.5:7.5, and the mass ratio of the bismuthate glass powder to the organic carrier is 7.5:1.

9. The method for low temperature joining of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (4), the glass paste is coated to a thickness of 90 to 120 μm.

10. The method for low-temperature connection of alumina ceramic and 1060 pure aluminum according to claim 1, wherein in the step (5), the connecting piece to be welded is preheated before welding, and is heated to 250 ℃ at a heating rate of 5-8 ℃/min, and is kept for 10-60 min; heating to 420-500 ℃ at a heating rate of 5-8 ℃/min during welding, and preserving heat for 10-40 min at the welding temperature.