CN106238710A - The solid-liquid method of attachment of aluminum aluminum metal - Google Patents

Abstract

The invention provides a solid-liquid connection method of aluminum-aluminum metal, which comprises the following steps: after protecting the surface of the solid aluminum material with a nickel layer, placing it in a mold cavity; pouring the molten aluminum material into the mold In the cavity, casting is carried out to form a metallurgical bond between the aluminum and aluminum metal materials, that is, to complete the solid-liquid connection of the aluminum and aluminum metals. Compared with the prior art, the present invention has the following beneficial effects: 1. Compared with the traditional welding method, it avoids the occurrence of problems such as oxidation slag inclusion, gas absorption, thermal cracking, and component segregation; 2. The connection method with solid In comparison, the connection between aluminum and aluminum of any shape can be realized theoretically due to the limited shape conditions; 3. The use of composite surface treatment technology solves the problem of surface oxide film very well, and can be used on the surface of solid aluminum pre-prepared materials Forms a uniform and continuous nickel layer to achieve a high level of aluminum-aluminum bond strength.

Description

Solid-liquid joining method of aluminum-aluminum metal

technical field

The invention relates to a solid-liquid connection method of aluminum-aluminum metal, which belongs to the field of preparation of bimetallic composite materials.

Background technique

As a representative of lightweight materials, aluminum alloys have been widely used in automobiles, electronics, aerospace and other industries. With the rapid development of industries and continuous advancement of technology, it is difficult to meet the requirements of material properties in various fields with a single casting or deformation material. Therefore, it is necessary to connect different materials together by welding, rolling, extrusion and other processes to maximize the advantages of different materials and make them have good comprehensive performance.

However, when using traditional welding methods to join aluminum-aluminum alloys, due to the unique physical and chemical properties of aluminum alloys, a series of problems such as oxidation slag inclusions, gas absorption, thermal cracking, and composition segregation often occur. After searching the existing technology, it is found that, in addition to the welding method, the common connection methods between aluminum and aluminum can be divided into solid-liquid connection and solid-solid connection according to the different material states. For the solid-solid connection method, some researchers have connected aluminum-aluminum alloys together by rolling and diffusion welding. However, since aluminum is very easy to oxidize in the atmospheric environment, especially under high temperature conditions, a dense oxide film is formed, which is serious. It hinders the interaction between metals, deteriorates the quality of the connection, and can only form a local metallurgical bond. In addition, oil stains and impurities on the surface will also affect the bonding process. At the same time, solid connection is often limited by equipment, and there are very strict requirements on the shape and size of materials, which also limits the promotion and application of aluminum alloy materials to a certain extent.

Compared with the solid-solid connection method, the solid-liquid composite technology has simple procedures, less constraints on shape conditions, simple process equipment requirements, and high production efficiency. It is an ideal method for aluminum-aluminum connection. After searching the prior art, it is found that this method has been widely used in steel (solid state)-casting (liquid state), cast iron (solid state)-aluminum alloy (liquid state), steel (solid state)-aluminum alloy (liquid state), Aluminum alloy (solid state)-magnesium alloy (liquid state), copper (solid state)-cast iron (liquid state) and other systems, the bimetallic composite materials prepared are widely used in various industrial fields, such as crusher hammer, aluminum clad steel core It has been proved to be a very cost-effective method for preparing bimetallic composite materials for skirting, automotive structural materials, etc. However, there are few reports on the formation of bimetallic materials through solid-liquid combination between aluminum (solid state) and aluminum (liquid state), because the oxide film on the surface of the aluminum alloy will affect the direct interaction between the solid-state aluminum alloy and the liquid aluminum material, As a result, its industrial application is limited.

Contents of the invention

Aiming at the defects in the prior art, the purpose of the present invention is to provide a solid-liquid connection method of aluminum-aluminum metal, which solves the problem that the existing aluminum-aluminum connection technology often causes oxidized slag inclusion, gas absorption, thermal cracking, and composition in the joint area. At the same time, the existence of oxide film will seriously affect a series of problems such as the interaction between the two metals and the performance of the connecting parts, so that the two aluminum alloys form a metallurgical bond with excellent mechanical properties.

The present invention is achieved through the following technical solutions:

The invention provides a method for solid-liquid connection of aluminum-aluminum metal, which comprises the following steps:

After the surface of the solid aluminum material is protected by a nickel layer, it is placed in the mold cavity;

The molten aluminum material is poured into the mold cavity and cast to form a metallurgical bond between the aluminum and aluminum materials, that is, to complete the solid-liquid connection of the aluminum and aluminum metals.

As a preferred solution, the solid aluminum material is pure aluminum or aluminum alloy.

As a preferred solution, the method for protecting the nickel layer is electroplating, chemical plating, hot-dip plating, thermal spraying or vapor deposition.

As a preferred solution, the thickness of the nickel layer is 0.1-10 μm.

As a preferred solution, the molten aluminum material is pure aluminum, cast aluminum alloy or deformed aluminum alloy.

As a preferred solution, the casting method is sand casting, metal casting, low pressure casting, high pressure casting, vacuum casting, squeeze casting or centrifugal casting.

As a preferred solution, in the squeeze casting, the casting temperature is 580-750° C., and the extrusion pressure is 0-120 MPa.

As a preferred solution, in the metal mold casting, the casting temperature is 580-750°C.

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

1. Compared with the traditional welding method, it avoids the occurrence of problems such as oxidation slag inclusion, gas absorption, thermal cracking, and composition segregation;

2. Compared with the solid connection method, it is less restricted by the shape conditions, and theoretically can realize the connection between aluminum-aluminum of any shape;

3. The problem of surface oxide film is well solved by using the composite surface treatment process, and a uniform and continuous nickel layer can be formed on the surface of the solid aluminum preset material, so that the connection strength between aluminum and aluminum can reach a higher level.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

Fig. 1 is the schematic diagram of the tensile strength test pattern of embodiment 1 of the present invention;

Fig. 2 is the metallographic diagram of the interface area between 6061 aluminum profiles and as-cast 6061 in Example 1 of the present invention;

Fig. 3 is the metallographic diagram of the 6061 aluminum profile and the as-cast A356 alloy interface area in Example 4 of the present invention;

Fig. 4 is a metallographic diagram of the interface area between the 6061 aluminum profile and the as-cast 6061 in Example 5 of the present invention.

detailed description

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

Example 1

An aluminum-aluminum connection method related to this embodiment includes the following steps:

Step 1. Nickel plating is performed on the 6061 plate to be connected, and the thickness of the nickel layer is 5 μm;

Step 2, melting and refining the cast 6061 to be poured;

Step 3, presetting the nickel-plated 6061 plate obtained in step 1 in the mold cavity;

Step 4. Using the metal mold casting method, pour liquid 6061 aluminum into the cavity of the mold at 720°C to form a metallurgical bond between aluminum and aluminum, that is, to complete the solid-liquid connection of aluminum-aluminum metal.

Figure 2 is the metallographic diagram of the 6061 plate and the as-cast interface area under this condition. From the figure, it can be observed that there are no defects such as oxidized slag inclusions, gas absorption, and hot cracks in the bonding area; a metallurgical bond is formed between the two materials, and the interface There is a continuous distribution of intermetallic oxides in the area, indicating the formation of a metallurgical bond between the two metals. After a tensile test (the spline is made into a dumbbell shape, as shown in Figure 1, the two ends are liquid cast metal parts 1, and the middle is a solid metal part 2. Compared with the base material's 132 MPa, the strength of the joint reaches 150 MPa.

Example 2

This embodiment relates to a solid-liquid connection method for an aluminum alloy, and the specific scheme is the same as that of Embodiment 1, except that:

In step 1, the thickness of the nickel layer is 1 μm;

The casting temperature in step 4 is 680°C.

The results show that under this condition, after the solid-liquid combination of solid 6061 aluminum alloy and 6061 cast aluminum alloy, there are no defects such as oxidized slag inclusions, gas absorption, thermal cracking, etc. in the bonding area; there is no obvious interface between the two aluminum alloys, forming a Metallurgical bonding, using the surface protection zinc layer to solve the problem that the oxide film hinders the formation of metallurgical bonding. After tensile test, the connection strength is 135MPa.

Example 3

This embodiment relates to a solid-liquid connection method for an aluminum alloy, and the specific scheme is the same as that of Embodiment 1, except that:

In step 1, the thickness of the nickel layer is 10 μm;

The casting temperature in step 4 is 750°C.

The results show that under this condition, after the solid-liquid combination of solid 6061 aluminum alloy and 6061 cast aluminum alloy, there are no defects such as oxidized slag inclusions, gas absorption, thermal cracking, etc. in the bonding area; there is no obvious interface between the two aluminum alloys, forming a Metallurgical bonding, using the surface protection zinc layer to solve the problem that the oxide film hinders the formation of metallurgical bonding. After tensile test, the connection strength is 145MPa.

Example 4

This embodiment relates to the connection method of A356 alloy and 6061, comprising the following steps:

Step 1. Nickel plating is performed on the solid aluminum preset material to be connected, and the thickness of the nickel layer is 3 μm;

Step 2, melting and refining the pure aluminum to be poured;

Step 3, presetting the solid red copper obtained in step 1 after the hot-dip galvanizing treatment in the mold cavity;

Step 4. Using the gravity casting method, the A356 alloy liquid is poured into the cavity of the mold at 720° C. to form a metallurgical bond between the two, that is, to complete the aluminum-aluminum solid-liquid connection.

Figure 3 is the metallographic diagram of the interface area between the A356 alloy and pure aluminum under this condition. It can be observed from the figure that a metallurgical bond is formed between the two materials, and there are continuously distributed intermetallic oxides in the interface area, indicating that a metallurgical bond is formed between the two metals. combined. After tensile test, the connection strength is 128MPa.

Example 5

This embodiment relates to a solid-liquid connection method for 6061 aluminum, comprising the following steps:

Step 1: Perform nickel plating on the 6061 aluminum preset material to be connected, and the thickness of the nickel layer is 5 μm;

Step 2, melting and refining the pure aluminum to be poured;

Step 3, presetting the nickel-plated solid aluminum obtained in step 1 in the mold cavity;

Step 4. Using the squeeze casting method, pour pure aluminum into the cavity of the mold at 720° C., and the extrusion pressure is 120 MPa to form a metallurgical bond between aluminum and aluminum, that is, to complete the solid-liquid connection of aluminum and aluminum.

Figure 4 is the metallographic diagram of the 6061 aluminum interface area under this condition. From the figure, it can be observed that there are no defects such as oxidation slag inclusions, gas absorption, and thermal cracks in the bonding area. A metallurgical bond is formed between the two materials, and there is a continuous distribution of intermetallic oxides in the interface area, indicating that a metallurgical bond is formed between the two metals. After tensile test, the connection strength is 142MPa.

Example 6

This embodiment relates to a solid-liquid connection method for an aluminum alloy, and the specific scheme is the same as that of Embodiment 5, except that:

In step 1, the thickness of the nickel layer is 0.1 μm;

The casting temperature in step 4 is 580° C., and the extrusion pressure is 80 MPa.

The results show that under this condition, after the solid-liquid combination of solid 6061 aluminum alloy and 6061 cast aluminum alloy, there are no defects such as oxidized slag inclusions, gas absorption, thermal cracking, etc. in the bonding area; there is no obvious interface between the two aluminum alloys, forming a Metallurgical bonding, using the surface protection zinc layer to solve the problem that the oxide film hinders the formation of metallurgical bonding. After tensile test, the connection strength is 135MPa.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention.

Claims (8)

1. a solid-liquid connection method of aluminum-aluminum metal, is characterized in that, comprises the steps: After the surface of the solid aluminum material is protected by a nickel layer, it is placed in the mold cavity; The molten aluminum material is poured into the mold cavity and cast to form a metallurgical bond between the aluminum and aluminum materials, that is, to complete the solid-liquid connection of the aluminum and aluminum metals. 2. The solid-liquid joining method of aluminum-aluminum metal according to claim 1, wherein the solid aluminum material is pure aluminum or aluminum alloy. 3. The solid-liquid connection method of aluminum-aluminum metal according to claim 1, characterized in that, the method for protecting the nickel layer is electroplating, electroless plating, hot-dip plating, thermal spraying or vapor deposition. 4. The solid-liquid bonding method of aluminum-aluminum metal according to claim 1 or 3, characterized in that the thickness of the nickel layer is 0.1-10 μm. 5. The solid-liquid joining method of aluminum-aluminum metal according to claim 1, wherein the molten aluminum material is pure aluminum, cast aluminum alloy or deformed aluminum alloy. 6. The solid-liquid connection method of aluminum-aluminum metal according to claim 1, wherein the casting method is sand casting, metal mold casting, low pressure casting, high pressure casting, vacuum casting, squeeze casting or centrifugal casting . 7 . The solid-liquid joining method of aluminum-aluminum metal according to claim 6 , characterized in that, in the squeeze casting, the casting temperature is 580-750° C., and the extrusion pressure is 0-120 MPa. 8. The solid-liquid joining method of aluminum-aluminum metal according to claim 6, characterized in that, in the metal mold casting, the casting temperature is 580-750°C.