CN112275799A - Steel-aluminum bimetallic rolling compound method with built-in groove interlocking - Google Patents

Abstract

The invention discloses a steel-aluminum bimetallic rolling composite method with embedded groove interlocking, which comprises the following steps: step S1 steel plate embedded groove processing, step S2 surface treatment, step S3 butt flattening Preloading is realized, the workpiece is preloaded and rolled in step S4, and heat treatment is performed in step S5; the present invention overcomes the problem that the steel-aluminum bimetal clad plate in the prior art needs a large reduction rate in a single pass to achieve preliminary cladding during clad rolling. By processing the embedded grooves at the contact surface of the steel plate, under the action of the embedded mechanical interlocking after being embedded with the aluminum plate, the steel-aluminum bimetal embedded preliminary composite is realized by multi-pass low-reduction rolling. And the obtained mechanical interlocking structure is used to increase the diffusion bonding effect during heat treatment, and fully improve the interface contact bonding strength.

Description

Steel-aluminum bimetallic rolling cladding method with built-in groove interlocking

technical field

The invention belongs to the technical field of composite materials and a preparation method thereof, in particular to a steel-aluminum bimetal rolling composite method with embedded groove interlocking.

Background technique

Steel-aluminum bimetallic plate composite, with steel as the matrix and aluminum as the reinforcement, the prepared aluminum plate reinforced steel matrix composite material has broad development space and application prospects in machinery, electronic appliances, aerospace, automobile and other industries. However, since aluminum will instantly form an oxide film in the air, which seriously hinders the recombination of steel and aluminum, it is necessary to roll with a large reduction rate to cause a large deformation of the aluminum plate, so that the oxide film on the surface of the aluminum plate is fully broken, and the fresh metal inside the aluminum plate is exposed. Bonds with steel.

The existing steel-aluminum cold-rolling composite method generally adopts a single-pass rolling reduction rate greater than 55% to form a preliminary steel-aluminum bond. At this time, the bond strength is low, and then it is strengthened by heat treatment. After the atoms are fully diffused, the interface forms a high level. Strength combination. However, the thickness of the steel-aluminum composite panel produced by this method is generally below 5mm. For the production of thick steel-aluminum clad plates by the cold-rolled cladding method, the single-pass reduction rate must be greater than 55% to achieve preliminary cladding. Otherwise, the steel and aluminum are easily separated after rolling, and the aluminum surface at the interface to be bonded is instantly re-oxidized In order to prevent recombination, it is also necessary to perform multi-pass rolling on the premise that the reduction ratio of the first pass is greater than 55%. However, the single-pass reduction ratio of thick-gauge steel-aluminum bimetallic plate rolling is greater than 55%, which requires high rolling capacity of the rolling mill equipment and is difficult to achieve.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention provides a steel-aluminum bimetal rolling composite method with embedded groove interlocking, which adopts the method of machining embedded grooves on the steel plate, and uses the mechanical interlocking structure obtained after rolling to make The steel and aluminum are closely attached to prevent the air from entering the interface to be composited, which can avoid the oxidation of the aluminum surface during re-rolling, so that the aluminum plate can be greatly deformed and the surface of the aluminum plate can be oxidized at a small reduction rate in multiple passes. A method in which the film is fully broken, and the fresh metal inside the aluminum plate is exposed and effectively combined with the steel; this method enables the steel plate and the aluminum plate to be embedded after multi-pass rolling to realize the steel-aluminum bimetal embedded rolling compound, and the obtained mechanical The interlocking structure increases the contact pressure between steel and aluminum during heat treatment, which is more conducive to the mutual diffusion of atoms to form a high-strength bond, realizes the cold-rolled composite of steel and aluminum under multiple passes and small pressure rates, and reduces the impact on the rolling capacity of the rolling mill equipment. Require.

In order to achieve the above purpose, the technical solution adopted in the present invention is to provide a steel-aluminum bimetal rolling composite method with embedded groove interlocking. The embedded groove is embedded with the aluminum plate and then rolled with a small reduction rate in multiple passes to realize the steel-aluminum bimetal embedded preliminary composite method, and the obtained mechanical interlocking structure is used to increase the diffusion bonding effect during heat treatment. The interface contact bonding strength is fully improved; on the other hand, the cold-rolled composite of steel and aluminum under multiple passes and small pressure ratios is realized, which reduces the requirements for the rolling capacity of the rolling mill equipment.

A steel-aluminum bimetal rolling composite method with embedded groove interlocking of the present invention, which comprises the following steps:

Step S1, embedded groove processing: the steel plate to be rolled is processed with embedded groove, and the shape of the embedded groove is a dovetail groove or an arc groove; by analyzing the composite plate with groove embedded The failure mode during rolling is derived from the relationship expression between the groove size, the thickness and width of the steel plate, and the thickness and width of the aluminum plate, so that the groove matching the aluminum plate to be rolled can be machined on the steel plate;

The relationship expression between the groove size of the dovetail groove, the thickness and width of the steel plate, and the thickness and width of the aluminum plate is:

b=a/2 (3)

Wherein, h is the groove depth of the steel plate to be rolled; h ₁ is the thickness of the steel plate to be rolled; h ₂ is the thickness of the aluminum plate to be rolled; a is the width of the steel plate to be rolled; b is the width of the aluminum plate to be rolled ;α is the dovetail groove angle;

The relationship expression between the groove size of the arc groove, the thickness and width of the steel plate, and the thickness and width of the aluminum plate is:

b=a/2 (6)

Wherein, h is the groove depth of the steel plate to be rolled; h ₁ is the thickness of the steel plate to be rolled; h ₂ is the thickness of the aluminum plate to be rolled; a is the width of the steel plate to be rolled; b is the width of the aluminum plate to be rolled;

Step S2, surface treatment: cleaning oxides and oil stains on the surfaces to be composited of the aluminum plate to be rolled and the steel plate to be rolled obtained in step S1;

Step S3, butt-flattening to achieve pre-assembly: an embedded groove or an arc-shaped groove is processed at the contact surface of the steel plate to be rolled, embedded with the aluminum plate to be rolled, and then pre-pressed and leveled by a hydraulic press to achieve preliminary docking and pre-assembly ;

Step S4, rolling the pre-installed workpiece: rolling the pre-installed workpiece in step S3 to realize the pre-compounding of the steel-aluminum bimetal embedded mechanically interlocked composite plate to obtain a pre-composite plate;

Step S5, heat treatment: the pre-composite plate in step S4 is subjected to a heat treatment process, and annealed in a temperature range of 350°C to 600°C for 1 hour.

Further, a milling machine or wire cutting is used to process the embedded groove in step S1.

Further, in the surface treatment of step S2, the oxides on the surface to be compounded are removed with a wire brush, sandpaper or a grinding wheel, and the oil stains on the surface to be compounded are wiped clean with acetone and alcohol, and then dried with a blower for use.

Further, the width of the aluminum plate to be rolled and the groove width of the steel plate to be rolled in step S3 have an interference amount, so that the interference fitting of the aluminum plate to be rolled and the steel plate to be rolled can be realized.

Further, in step S4, multi-pass cold rolling is performed on the rolling mill for the rolling of the preloaded workpiece, the rolling speed is 0.1-5 m/s, and the single-pass reduction rate is 10%-60%, and the obtained steel plate is the same as The embedded preliminary mechanical interlocking structure of the aluminum plate; then multi-pass rolling is performed to ensure that the total cold rolling reduction rate is greater than 55%, and the preliminary composite of the steel-aluminum bimetal clad plate is realized, and the shear strength of the clad plate is above 74MPa .

Further, in step S5, the pre-clad plate is annealed for 1 h and then cooled in the furnace, thereby obtaining a steel-aluminum bimetallic clad plate.

Because the present invention adopts the above-mentioned technical scheme, the present invention has the following beneficial effects:

(1) Compared with the existing steel-aluminum bimetal cladding process, the present invention overcomes the problem that the steel-aluminum bimetal clad plate in the prior art needs a single-pass larger reduction ratio to realize preliminary cladding during clad rolling. , By preparing shear specimens, under the condition that the total reduction rate of two passes is greater than 58%, the shear strength of the composite plate measured by the tensile testing machine is more than 74MPa, compared with the same reduction rate in a single pass. Rolling under conditions reduces the requirement of rolling capacity of the rolling mill equipment, and the composite strength is more than 15MPa higher than that of a single pass.

(2) The steel-aluminum bimetal rolling composite method with embedded groove interlocking of the present invention can realize large deformation of the aluminum plate at a small reduction rate of multiple passes, so that the oxide film on the surface of the aluminum plate is fully broken, and the aluminum plate can be completely broken. The internal fresh metal is exposed and effectively combined with the steel;

(3) In the present invention, the embedded groove is processed at the contact surface of the steel plate, and after being embedded with the aluminum plate, the steel-aluminum bimetal embedded preliminary composite is realized by multi-pass low-reduction rolling, and the obtained mechanical On the one hand, the interlocking structure increases the diffusion bonding effect during heat treatment, which is more conducive to the mutual diffusion of atoms to form high-strength bonding, which fully improves the interface contact bonding strength; Reduced requirements for rolling capacity of rolling mill equipment.

(4) The reduction ratio required for a single pass of the cold-rolled steel-aluminum clad plate to achieve mechanical occlusion or pre-cladding needs to be greater than 55%, and it is difficult for the rolling equipment to provide the rolling force required for the cladding. Therefore, considering the rolling capacity of the rolling equipment, most of the existing clad plate rolling process adopts the hot rolling process, while the present invention realizes the completion of mechanical clinching or pre-compounding by single-pass small reduction, and multi-pass small reduction cooling. Cold-rolled cladding can be achieved after rolling. Compared with hot-rolling, the cold-rolling cladding method has the advantages of high product dimensional accuracy, good surface quality, and the thickness ratio of the product can be adjusted arbitrarily without being limited by the thickness of the coating. The invention also has the advantages of low production cost, high efficiency, convenient industrial production and the like. In addition, there is no interface oxidation caused by heating of the billet, and it is difficult to generate intermetallic compounds at the interface. Better quality composite panels can be obtained.

Description of drawings

Fig. 1 is the inventive flow chart of the steel-aluminum bimetallic rolling compound method with embedded groove interlocking of the present invention;

Fig. 2a is the schematic diagram of surface processing dovetail groove of steel plate to be rolled by the steel-aluminum bimetal rolling composite method with embedded groove interlocking according to the present invention;

Figure 2b is a schematic diagram of the butt-insertion of the to-be-rolled aluminum plate of the present invention;

3a is a schematic diagram of the surface machining of arc grooves on the steel plate to be rolled according to the steel-aluminum bimetal rolling composite method with embedded groove interlocking according to the present invention;

Figure 3b is a schematic diagram of the butt-insertion of the to-be-rolled aluminum plate according to the present invention;

Fig. 4 is a shear strength-strain relationship diagram with a total reduction ratio of 58% in Example 1;

5 is a graph showing the shear strength-strain relationship of Example 2 with a total reduction ratio of 65%.

In the drawings, the main reference signs:

5052 aluminum plate 1; Q235 steel plate 2.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the usual meanings understood by those skilled in the art to which the present invention belongs.

The technical solutions of the present invention will be further described in detail below through examples and in conjunction with the accompanying drawings.

As shown in FIG. 1, a steel-aluminum bimetal rolling compound method with embedded groove interlocking of the present invention comprises the following steps:

Step S1, embedded groove processing: the steel plate to be rolled is subjected to embedded groove processing, and the shape of the groove is set as a dovetail groove or an arc groove; by analyzing the rolling of the clad plate with groove embedded The relationship expression between the groove size, the thickness and width of the steel plate, and the thickness and width of the aluminum plate can be obtained, and the groove matching the aluminum plate to be rolled can be processed, including the grooving of the processing groove. Depth and slot angle size;

The relationship expression between the groove size of the dovetail groove, the thickness and width of the steel plate, and the thickness and width of the aluminum plate is:

b=a/2 (3)

Wherein, h is the groove depth of the steel plate to be rolled; h ₁ is the thickness of the steel plate to be rolled; h ₂ is the thickness of the aluminum plate to be rolled; a is the width of the steel plate to be rolled; b is the width of the aluminum plate to be rolled ;α is the dovetail groove angle;

The relationship expression between the groove size of the arc groove, the thickness and width of the steel plate, and the thickness and width of the aluminum plate is:

b=a/2 (6)

Wherein, h is the groove depth or groove diameter of the steel plate to be rolled; h ₁ is the thickness of the steel plate to be rolled; h ₂ is the thickness of the aluminum plate to be rolled; a is the width of the steel plate to be rolled; b is the thickness of the steel plate to be rolled; the width of the aluminum plate;

Step S2, surface treatment: cleaning oxides and oil stains on the surfaces to be composited of the aluminum plate to be rolled and the steel plate to be rolled obtained in step S1;

Step S3, butt-flattening to achieve pre-assembly: an embedded groove or an arc-shaped groove is processed at the contact surface of the steel plate to be rolled, embedded with the aluminum plate to be rolled, and then pre-pressed and leveled by a hydraulic press to achieve preliminary docking and pre-assembly ;

Step S4, rolling the pre-installed workpiece: rolling the pre-installed workpiece in step S3 to realize the pre-compounding of the steel-aluminum bimetal embedded mechanically interlocked composite plate;

Step S5, heat treatment: the pre-composite plate in step S4 is subjected to a heat treatment process, and annealed in a temperature range of 350°C to 600°C for 1 hour.

Example 1

As shown in Figure 2, Example 1 is an example of composite rolling of Q235 steel plate 2 to be rolled and dovetail groove processing and 5052 aluminum plate 1 to be rolled;

Step S1, processing of embedded dovetail grooves: the Q235 steel plate 2 with a width of 30mm is processed into embedded dovetail grooves by a milling machine, and a groove angle of 45°, a groove depth of 2mm, a steel plate thickness of 5mm, and a 5052 aluminum plate are selected through the calculation formula of the dovetail groove. 1 Thickness 4mm, width 15mm, the length of the steel plate and aluminum plate should be greater than the width;

Step S2, surface treatment: remove oxides on the surfaces to be composited of the 5052 aluminum plate 1 and the Q235 steel plate 2 of the steel-aluminum bimetal plate obtained in step S1 with a wire brush, sandpaper or grinding wheel, and use acetone and alcohol to wipe the oil stains on the surfaces to be composited Clean, then blow dry with a hair dryer;

Step S3, butt flattening to achieve pre-installation: an embedded dovetail groove is processed at the contact surface of the Q235 steel plate 2, embedded with the 5052 aluminum plate 1, and then pre-pressed and flattened by a hydraulic press to achieve preliminary docking and pre-installation;

Step S4, rolling of pre-installed workpiece: the first pass of pre-installed workpiece is rolled at a reduction rate of 30% to realize the embedded preliminary mechanical interlocking of Q235 steel plate 2 and 5052 aluminum plate 1, and then the second pass is reduced by 40% It can realize the pre-compounding of steel-aluminum composite panels at a high rate;

Step S5, heat treatment: the pre-clad plate is annealed at 400° C. for 1 hour, and cooled with the furnace to obtain a steel-aluminum clad metal plate.

By preparing shear specimens, the shear strength of the composite plate measured by the tensile testing machine was 74MPa under the condition of the total reduction rate of 58% in two passes (as shown in Figure 4), compared with the single pass pressure Rolling under the condition of a reduction rate of 58%, this patent reduces the requirement of the rolling capacity of the rolling mill equipment, and the composite strength is increased by nearly 15MPa compared with a single pass.

Example 2

As shown in FIG. 3 , Example 2 is an example of composite rolling of the Q235 steel plate 2 to be rolled with arc grooves and the 5052 aluminum plate 1 to be rolled.

Step S1, embedded groove processing: the Q235 steel plate 2 with a width of 10mm is processed into an embedded groove by a milling machine, and the groove depth is 2mm, the thickness of the steel plate is 5mm, and the 5052 aluminum plate to be rolled is selected according to the calculation formula of the arc groove parameters. 1 Thickness 4mm, width 5mm, the length of the steel plate and aluminum plate should be greater than the width;

Step S2, surface treatment: remove oxides on the contact surface of Q235 steel plate 2 and 5052 aluminum plate 1 with a wire brush, sandpaper or grinding wheel, wipe it clean with acetone and alcohol, and then dry it with a hair dryer for use;

Step S3, butt flattening to realize pre-installation: insert the 5052 aluminum plate 1 into the slotted Q235 steel plate 2, and then use a hydraulic press to pre-press and flatten to achieve preliminary docking and pre-installation;

Step S4, rolling of the preloaded workpiece: the first pass of the preloaded workpiece is rolled at a reduction rate of 30% to realize the embedded preliminary mechanical interlocking of the Q235 steel plate 2 and the 5052 aluminum plate 1, and then the second and third passes are respectively 30 % reduction rate to achieve pre-composite steel-aluminum composite plate;

Step S5, heat treatment: the pre-clad plate is annealed at 450° C. for 1 hour, and cooled with the furnace to obtain a steel-aluminum clad metal plate.

Under the condition of the total reduction rate of 65% in three passes, the shear strength of the composite plate measured by the tensile testing machine is 81MPa (as shown in Figure 5), compared with the condition of the single pass reduction rate of 65% For lower rolling, this patent reduces the requirement of rolling capacity of the rolling mill equipment, and the composite strength is increased by nearly 20MPa compared with a single pass.

To sum up, the prepared steel-aluminum bimetallic clad plate has better composite state and diffusion conditions than the same reduction rate and the same kind of steel-aluminum bimetallic clad plate, and thus has better mechanical properties. The mechanical interlocking structure increases the contact pressure between steel and aluminum during heat treatment, which is more conducive to the mutual diffusion of atoms to form a high-strength bond, realizes the cold-rolled composite of steel and aluminum under multiple passes and small pressure rates, and reduces the rolling capacity of the rolling mill equipment. requirements.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (6)

1. A rolling compounding method of steel-aluminum bimetal with embedded groove interlocking is characterized by comprising the following steps:

step S1, processing the embedded groove: processing an embedded groove of a steel plate to be rolled, wherein the embedded groove is in a dovetail groove or an arc groove shape; obtaining a relational expression among the size of the groove, the thickness and the width of the steel plate and the thickness and the width of the aluminum plate by analyzing a failure mode when the composite plate with the embedded groove is rolled, and realizing the processing of the groove matched with the aluminum plate to be rolled on the steel plate;

the relational expressions between the groove size of the dovetail groove, the thickness and width of the steel plate, and the thickness and width of the aluminum plate are:

b＝a/2 (3)

wherein h is the slotting depth of the steel plate to be rolled; h is₁Is the thickness of the steel plate to be rolled; h is₂Is the thickness of the aluminum plate to be rolled; a is the width of the steel plate to be rolled; b is the width of the aluminum plate to be rolled; alpha is a dovetail groove angle;

the relational expressions among the groove size of the arc-shaped groove, the thickness and width of the steel plate and the thickness and width of the aluminum plate are as follows:

b＝a/2 (6)

wherein h is the grooving depth or the groove diameter of the steel plate to be rolled; h is₁Is the thickness of the steel plate to be rolled; h is₂Is the thickness of the aluminum plate to be rolled; a is the width of the steel plate to be rolled; b is the width of the aluminum plate to be rolled;

step S2, surface treatment: cleaning the oxide and oil stains on the surface to be compounded of the aluminum plate to be rolled and the steel plate to be rolled obtained in the step S1;

step S3, butting and flattening to realize pre-assembly: processing an embedded groove or an arc-shaped groove at the contact surface of the steel plate to be rolled, embedding the embedded groove or the arc-shaped groove with the aluminum plate to be rolled, and then, prepressing and flattening by using a hydraulic machine to realize preliminary butt joint preassembly;

step S4, rolling the pre-assembled workpiece: rolling the pre-installed workpiece in the step S3 to realize pre-compounding of the steel-aluminum bimetal embedded mechanical interlocking composite plate to obtain a pre-composite plate;

step S5, heat treatment: and (4) carrying out a heat treatment process on the pre-clad plate in the step S4, and annealing for 1h at the temperature of 350-600 ℃.

2. The steel-aluminum bimetal roll cladding method with in-line groove interlocking of claim 1, wherein the in-line groove machining of step S1 is performed by a milling machine or wire cutting.

3. The steel-aluminum bimetal rolling compounding method with the embedded groove interlock according to claim 1, wherein in the step S2, the surface treatment is performed by removing oxides on the surface to be compounded with a wire brush, a sand paper or a grinding wheel, wiping oil stains on the surface to be compounded with acetone and alcohol, and drying the surface to be compounded with a fan for later use.

4. The steel-aluminum bimetal rolling compounding method with in-line groove interlocking according to claim 1, wherein the width of the aluminum plate to be rolled and the width of the groove of the steel plate to be rolled in the step S3 have interference, so that the interference fitting of the aluminum plate to be rolled and the steel plate to be rolled can be realized.

5. The steel-aluminum bimetal rolling compounding method with the embedded groove interlocking function according to claim 1, wherein in the step S4, the pre-assembled workpiece is rolled by a rolling mill for multiple cold rolling, the rolling speed is 0.1-5 m/S, the single reduction is 10% -60%, and an embedded preliminary mechanical interlocking structure of the steel plate and the aluminum plate is obtained; and then multi-pass rolling is carried out, the total reduction rate of cold rolling is ensured to be more than 55 percent, the primary compounding of the steel-aluminum bimetal composite plate is realized, and the shearing strength of the composite plate is more than 74 MPa.

6. The method for roll-cladding steel-aluminum bimetal with embedded groove interlocking according to claim 1, wherein the pre-clad plate is annealed for 1 hour in step S5 and then cooled with a furnace, thereby obtaining the steel-aluminum bimetal composite plate.

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