Method for rolling large-thickness steel / aluminum composite material by rapidly heating core part
By using a rapid core heating method, the problems of warping and energy consumption during the rolling process of thick steel/aluminum composite materials were solved, the interfacial bonding strength and production efficiency were improved, and high-quality composite material preparation was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TAIYUAN UNIVERSITY OF TECHNOLOGY
- Filing Date
- 2026-02-12
- Publication Date
- 2026-04-17
AI Technical Summary
In the rolling process of thick steel/aluminum composite materials, traditional integral heating leads to problems such as warping and metal accumulation, and consumes a lot of energy, affecting the interfacial bonding strength and matrix properties.
A core rapid heating method is adopted to hot roll a thick steel plate and a thin aluminum plate together, and weld supporting aluminum blocks on the aluminum side. The core of the billet is heated by high temperature gas to reduce the interface gap before being rolled by pinch rolls, so as to achieve large deformation with small reduction rate.
This improved the interfacial bonding strength, reduced energy consumption, avoided the effects of residual heat, and enabled the preparation of high-quality steel/aluminum composite materials.
Smart Images
Figure CN121869859A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of metal layered composite material preparation technology, specifically relating to a method for rapidly heating and rolling a thick steel / aluminum composite material in the core. Background Technology
[0002] Thick-film steel / aluminum composites, combining the high strength of steel with the lightweight, high corrosion resistance, and electrical conductivity of aluminum, have found widespread application in critical fields such as aerospace, shipbuilding, and power. For example, in the shipbuilding industry, thick-film steel / aluminum composites can be cut and fabricated into steel-aluminum structural transition joints. This structure enables an efficient and reliable connection between the upper aluminum alloy structure and the main steel structure of the ship, making it a key component for ship lightweighting. Simultaneously, heavy-duty, low-speed bearing bushes made from thick-film steel / aluminum composites, thanks to the material's excellent thermal conductivity, can quickly dissipate heat from bearing components, effectively extending bearing life and ensuring stable equipment operation. Furthermore, thick-film steel / aluminum composites can also be used to manufacture conductive joints for anodes in the electrolytic aluminum industry, an indispensable key component of electrolytic anodes.
[0003] Currently, the main methods for preparing thick steel / aluminum composites include rolling composite and explosive composite. Explosive composite is an important method for the industrial production of thick steel / aluminum composites, and its products have been widely used. However, due to limitations of the explosive composite process, steel and aluminum alloys cannot be directly explosively bonded together; an intermediate pure aluminum layer is required. Furthermore, overmelting easily occurs at the steel-aluminum interface during the explosion process, resulting in uneven diffusion layer thickness and significant residual stress, severely limiting the improvement of the bonding strength of the steel / aluminum composite, and consequently restricting the application of thick steel / aluminum composites. Compared to explosive composite, rolling composite has gradually become one of the mainstream processes for preparing layered metal composites due to its advantages such as high production efficiency, good interfacial bonding quality, and scalability. As is well known, during the rolling composite process of thick steel / aluminum composites, the interfacial bonding strength of the composite plate is mainly affected by interfacial temperature, interfacial pressure, and interfacial shear force.
[0004] In the rolling process of thick steel / aluminum composites with relatively small differences in component thickness, the interfacial shear force is low because the interface is close to the neutral layer. To improve the interfacial bonding strength, the rolling reduction rate needs to be increased. However, due to the significant differences in the metallic properties of steel and aluminum, when both steel and aluminum components are thick, the traditional rolling process, which involves heating both steel and aluminum as a whole, results in deformation primarily on the aluminum side, easily leading to problems such as slab warping and metal accumulation, affecting continuous rolling. Furthermore, because both steel and aluminum are thick, the residual heat after rolling requires a long cooling time, resulting in energy consumption and a decrease in the bonding performance of the component metal matrix and the interface. Therefore, there is an urgent need to develop a method for preparing thick steel / aluminum composites that can increase the interfacial deformation during rolling, reduce energy consumption, and avoid the impact of residual heat on the properties of the component matrix and the bonding interface. Summary of the Invention
[0005] To address the aforementioned problems, this invention provides a method for rapidly heating and rolling thick steel / aluminum composite materials in the core. The method involves first hot-rolling a thick steel plate and a thin aluminum plate together, then bonding the thick aluminum plate (with welded supporting aluminum material) to the billet obtained in the previous step. After heating and being fed by pinch rolls, the mixture is rolled to form a thick steel / aluminum composite material. This method effectively increases the interfacial deformation during rolling, reduces energy consumption, and avoids residual heat affecting the matrix properties and bonding interface properties, thereby achieving high-quality preparation of thick steel / aluminum composite materials.
[0006] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a method for rapidly heating and rolling a thick steel / aluminum composite material in the core, comprising the following steps: The surfaces of the thick steel plate and the thin aluminum plate to be composited are ground separately, then heated to 100-300℃, and rolled once to obtain a high-thickness steel / aluminum composite material. The aluminum side of the high-thickness steel / aluminum composite material is ground to obtain billet 1, which is ready for use. A cuboid aluminum block of the same material and thickness as the thick aluminum plate is welded to the surface of the thick aluminum plate to be composited, and the side with the welded cuboid aluminum block is ground to obtain billet 2, which is ready for use. The length and width of billet 1 and billet 2 are completely aligned and fixed to obtain a high-thickness steel / aluminum composite material assembly billet. The high-temperature gas at 450-530℃ is passed through the gap between billet 1 and billet 2 to heat the high-thickness steel / aluminum composite material assembly billet for 10-40 minutes, and then pinch rolls are used to reduce the gap between billet 1 and billet 2. Finally, the high-thickness steel / aluminum composite material assembly billet after pinch rolls is rolled a second time to obtain the high-thickness steel / aluminum composite material. The thickness of the thick steel plate is ≥20mm; the thickness of the thin aluminum plate is 1-6mm; the thickness of the thick aluminum plate is ≥20mm. The pressure of the pinch rollers Where k is a coefficient, ranging from 1.3 to 2; σ is the deformation resistance of the cuboid aluminum block, MPa; b is the width of the cuboid aluminum block, mm; and l is the length of the cuboid aluminum block, mm.
[0007] Optionally, the thick steel plate is selected from carbon steel or alloy steel.
[0008] Optionally, the thin aluminum plate and the thick aluminum plate are selected from 1-series, 2-series, 3-series, 5-series, 6-series or 7-series aluminum alloys, respectively.
[0009] Preferably, the roughness of the composite surface of the thick steel plate after grinding is Ra25.
[0010] Preferably, the roughness of the composite surface of the thin aluminum plate after polishing is Ra12.5.
[0011] Preferably, the reduction rate of the single rolling is 10% to 20%.
[0012] Preferably, the roughness of the blank 1 after polishing is Ra12.5.
[0013] Preferably, the length of the cuboid aluminum block is 2-4 mm and the width is 1-2 mm.
[0014] Preferably, the cuboid aluminum blocks are placed at 0.5m intervals along the length of the thick aluminum plate, with at least two rows placed.
[0015] The placement of the rectangular aluminum block can be referenced. Figure 2 .
[0016] Preferably, the roughness of the blank 2 after polishing is Ra12.5.
[0017] Preferably, the reduction rate of the secondary rolling is 15% to 40%.
[0018] The beneficial technical effects of the present invention are as follows: It can achieve large interface deformation with small reduction rate: Compared with traditional integral heating rolling, the core rapid heating method adopted in this invention can make the core temperature of the billet higher than the surface temperature, that is, the temperature of the composite surface is higher than the plate surface in contact with the roll. According to the rolling principle, the interface will be more likely to deform during the rolling process, thereby achieving large interface deformation with small reduction rate, which is conducive to promoting interface composite.
[0019] Reduced energy consumption and avoidance of residual heat impact on composite plates: Compared with traditional overall heating, the core rapid heating method used in this invention only heats the metal near the core of the billet, i.e., the interface to be composited. This can quickly raise the temperature of the interface to be composited without heating the entire billet. This will greatly shorten the heating time, effectively reduce the heat required for heating, and achieve energy saving. At the same time, the residual heat after rolling is significantly reduced compared with traditional heating methods, effectively avoiding the impact of residual heat after rolling on the interfacial bonding performance and matrix properties. Continuous production is possible: Each step of the present invention can be carried out continuously, the parameters of each step are easy to control precisely, the production efficiency is high, it can meet the needs of fast-paced continuous production, shorten the production cycle of composite material heat treatment, meet the requirements of fast-paced industrial production, and is conducive to large-scale promotion and application. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 A process flow diagram for preparing thick steel / aluminum composite materials according to an embodiment of the present invention; Figure 2 This refers to the location of the cuboid aluminum block spot-welded to the thick aluminum plate in this embodiment of the invention; Among them, 1 is a thick steel plate, 2 is a grinding machine, 3 is a thin aluminum plate, 4 is a conventional heating furnace, 5 is a thick aluminum plate, 6 is a rectangular aluminum block, 7 is the No. 1 rolling mill, 8 is a rivet, 9 is a circulation component, 10 is a heat pump, 11 is a high-thickness steel / aluminum composite billet assembly, 12 is a specific heating furnace body, 13 is a centering device, 14 is a pinch roll, and 15 is the No. 2 rolling mill. Detailed Implementation
[0022] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.
[0023] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.
[0024] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0025] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention.
[0026] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0027] Figure 1 A process flow diagram for preparing thick steel / aluminum composite materials according to an embodiment of the present invention; Figure 2 This refers to the location of the cuboid aluminum block spot-welded to the thick aluminum plate in this embodiment of the invention; Among them, 1 is a thick steel plate, 2 is a grinding machine, 3 is a thin aluminum plate, 4 is a conventional heating furnace, 5 is a thick aluminum plate, 6 is a rectangular aluminum block, 7 is the No. 1 rolling mill, 8 is a rivet, 9 is a circulation component, 10 is a heat pump, 11 is a high-thickness steel / aluminum composite billet assembly, 12 is a specific heating furnace body, 13 is a centering device, 14 is a pinch roll, and 15 is the No. 2 rolling mill.
[0028] Example 1 The thick steel plate used in this embodiment is Q235B steel (length × width × height is 200mm × 100mm × 20mm), the thin aluminum plate is 1060 aluminum (length × width × height is 200mm × 100mm × 1mm), and the thick aluminum plate is 5083 aluminum (length × width × height is 200mm × 100mm × 20mm).
[0029] A method for rapidly heating and rolling a thick steel / aluminum composite material in the core, comprising the following steps: S1, Preparation of high-thickness steel / aluminum composite material: Prepare 1060 thin aluminum plate 3 and remove oil and oxide film from its surface. Use a wire brush to roughen the surface of the 1060 thin aluminum plate 3 to be composited. The surface roughness after grinding is Ra12.5. Prepare Q235B thick steel plate 1 and remove oil and oxide film from its surface. Use a diamond to roughen the surface of the Q235B thick steel plate to be composited. The surface roughness after grinding is Ra25. The roughened 1060 thin aluminum plate 3 and Q235B thick steel plate 1 are placed in a conventional heating furnace 4 and heated to 200°C. The composite is rolled with a 10% reduction rate through a rolling mill, and then straightened and cut to obtain a steel / aluminum composite material with a large thickness ratio.
[0030] S2, Thick Steel / Aluminum Composite Material Preform: Remove oil and oxide film from the aluminum side of the thick steel / aluminum composite material obtained in step S1, and roughen it with a wire brush to a surface roughness of Ra12.5, then let it stand for later use; Take a thick aluminum plate 1 with the same length and width as the thick steel / aluminum composite material prepared in S1, and place it around the perimeter of the surface to be composited on the 5083 thick aluminum plate 1 (positions as shown in the image). Figure 2(As shown) Spot weld 5083 cuboid aluminum blocks 6, with the same material as the thick aluminum plate substrate, 2mm in length, 1mm in width, and 1mm in thickness, to prepare a thick aluminum plate with 5083 cuboid aluminum blocks 6; use a wire brush to roughen the cuboid surface of the thick aluminum plate with cuboid aluminum blocks, and the surface roughness after grinding is Ra12.5, and then let it stand for later use; assemble the ground high-thickness steel / aluminum composite material with the thick aluminum plate with cuboid aluminum blocks, so that the ground surface of the thick aluminum plate with cuboid aluminum blocks is in contact with the ground surface of the high-thickness steel / aluminum composite material, and the length and width are completely aligned, and rivet 8 is used to rivet the head of the assembly, so that a 1mm gap is formed between the aluminum surface of the high-thickness steel / aluminum composite material and the thick aluminum plate with cuboid aluminum blocks, to obtain the high-thickness steel / aluminum composite material assembly 11.
[0031] S3, rapid heating of the core of the billet: The thick steel / aluminum composite billet 11 from step S2 is placed into a specific heating furnace body 12, so that the high-temperature gas from the heat pump 10 flows through the gap between the thick aluminum plate with the large thickness ratio steel / aluminum composite material and the billet along the width direction, thereby achieving rapid heating of the core. The heating time is 10 minutes and the high-temperature gas temperature is 500℃.
[0032] S4, Centering and Hot Pressing: The assembled billet heated in step S3 is centered and held using centering device 13, and then pressure-pressed using pinch roller 14 (the pressure applied by pinch roller 14 is calculated to be 1.2KN), so that the gap between the steel / aluminum composite material with large thickness ratio and the thick aluminum plate with rectangular aluminum block is reduced, forming a billet with small gaps.
[0033] S5, Rolling and Forming of Thick Steel / Aluminum Composite Plates: The micro-void billet obtained in step S4 is fed into rolling mill 15 (No. 2) and rolled at a reduction rate of 25%. After straightening and cutting, thick steel / aluminum composite materials are prepared. Mechanical property tests were conducted on the composite material samples using methods derived from GB / T 6396-2008 "Test Methods for Mechanical and Technological Properties of Composite Steel Plates". The results showed that its shear strength reached 65 MPa and its bond strength reached 120 MPa.
[0034] Example 2 The thick steel plate used in this embodiment is 304 steel (length × width × height is 600mm × 400mm × 20mm), the thin aluminum plate is 6061 aluminum (length × width × height is 600mm × 400mm × 3mm), and the thick aluminum plate is 6061 aluminum (length × width × height is 600mm × 400mm × 30mm).
[0035] A method for rapidly heating and rolling a thick steel / aluminum composite material in the core, comprising the following steps: S1, Preparation of high-thickness steel / aluminum composite material: Prepare 6061 thin aluminum plate 3 and remove oil and oxide film from its surface. Use a wire brush to roughen the surface of the 6061 thin aluminum plate 3 to be composited. The surface roughness after grinding is Ra12.5. Prepare 304 thick steel plate 1 and remove oil and oxide film from its surface. Use a diamond to roughen the surface of the 304 thick steel plate to be composited. The surface roughness after grinding is Ra25. The roughened 6061 thin aluminum plate 3 and 304 thick steel plate 1 are placed in a conventional heating furnace 4 and heated to 200°C. They are then rolled together by a rolling mill with a reduction rate of 20%. After straightening and cutting, a high-thickness steel / aluminum composite material is obtained.
[0036] S2, Large Thickness Steel / Aluminum Composite Material Preform: Remove oil and oxide film from the aluminum side of the large thickness ratio steel / aluminum composite material obtained in step S1, and roughen it with a wire brush to a surface roughness of Ra12.5, then let it stand for later use; Take a thick aluminum plate 1 with the same length and width as the large thickness ratio steel / aluminum composite material prepared in S1, and place it around the perimeter of the surface to be composited on the 6061 thick aluminum plate 1 (positions as shown in the image). Figure 2 (As shown) Spot weld 6061 cuboid aluminum blocks 6, which are the same material as the thick aluminum plate substrate, with a length of 3mm, a width of 2mm, and a thickness of 2mm, to prepare a thick aluminum plate with 6061 cuboid aluminum blocks 6; use a wire brush to roughen the cuboid surface of the thick aluminum plate with cuboid aluminum blocks, and the surface roughness after grinding is Ra12.5, and then let it stand for later use; assemble the thick aluminum plate with cuboid aluminum blocks and the ground surface of the thick aluminum plate with cuboid aluminum blocks, so that the thick aluminum plate with cuboid aluminum blocks and the ground surface of the thick aluminum plate with cuboid aluminum blocks are in contact, and the length and width are completely aligned, and rivet 8 is used to rivet the head of the assembly, so that a 2mm gap is formed between the aluminum surface of the thick aluminum plate with cuboid aluminum blocks and the thick aluminum plate with cuboid aluminum blocks, to obtain the thick steel / aluminum composite assembly 11.
[0037] S3, rapid heating of the core of the billet: The thick steel / aluminum composite billet 11 from step S2 is placed into a specific heating furnace body 12, so that the high-temperature gas from the heat pump 10 flows through the gap between the thick aluminum plate with the large thickness ratio steel / aluminum composite material and the billet along the width direction. The heating time is 25 minutes and the high-temperature gas temperature is 500℃.
[0038] S4, centering and hot pressing: The assembled billet heated in step S3 is centered and held using centering device 13, and then pressure-pressed using pinch roller 14 (the pressure applied by pinch roller 14 is calculated to be 2.6KN), so that the gap between the steel / aluminum composite material with large thickness ratio and the thick aluminum plate with rectangular aluminum block is reduced, forming a billet with small gaps.
[0039] S5, Rolling and Forming of Thick Steel / Aluminum Composite Plates: The micro-void billet obtained in step S4 is fed into rolling mill 15 (No. 2) and rolled at a reduction rate of 35%. After straightening and cutting, thick steel / aluminum composite materials are prepared. Mechanical property tests were conducted on the composite material samples using methods derived from GB / T 6396-2008 "Test Methods for Mechanical and Technological Properties of Composite Steel Plates". The results showed that its shear strength reached 98.5 MPa and its bond strength reached 161.4 MPa.
[0040] Example 3 The thick steel plate used in this embodiment is 40Cr steel (length × width × height is 1000mm × 200mm × 30mm), the thin aluminum plate is 3003 aluminum (length × width × height is 1000mm × 200mm × 3mm), and the thick aluminum plate is 7075 aluminum (length × width × height is 1000mm × 200mm × 20mm).
[0041] A method for rapidly heating and rolling a thick steel / aluminum composite material in the core, comprising the following steps: S1, Preparation of high-thickness steel / aluminum composite material: Prepare 3003 thin aluminum plate 3 and remove oil and oxide film from its surface. Use a wire brush to roughen the surface of the 3003 thin aluminum plate 3 to be composited. The surface roughness after grinding is Ra12.5. Prepare 40Cr thick steel plate 1 and remove oil and oxide film from its surface. Use a diamond to roughen the surface of the 40Cr thick steel plate to be composited. The surface roughness after grinding is Ra25. The roughened 3003 thin aluminum plate 3 and 40Cr thick steel plate 1 are placed in a conventional heating furnace 4 and heated to 300℃. They are then rolled together by a rolling mill with a reduction rate of 20%. After straightening and cutting, a high-thickness steel / aluminum composite material is obtained.
[0042] S2, Large Thickness Steel / Aluminum Composite Material Preform: Remove oil and oxide film from the aluminum side of the large thickness ratio steel / aluminum composite material obtained in step S1, and roughen it with a wire brush to a surface roughness of Ra12.5, then let it stand for later use; Take a thick aluminum plate 1 with the same length and width as the large thickness ratio steel / aluminum composite material prepared in S1, and place it around the perimeter of the surface to be composited on the 7075 thick aluminum plate 1 (positions as shown in the image). Figure 2(As shown) Spot weld 7075 cuboid aluminum blocks 6, with the same material as the thick aluminum plate substrate, 4mm in length, 2mm in width, and 3mm in thickness, to prepare a thick aluminum plate with 7075 cuboid aluminum blocks 6; use a wire brush to roughen the cuboid surface of the thick aluminum plate with cuboid aluminum blocks, and the surface roughness after grinding is Ra12.5, and then let it stand for later use; assemble the ground high-thickness steel / aluminum composite material with the thick aluminum plate with cuboid aluminum blocks, so that the ground surface of the thick aluminum plate with cuboid aluminum blocks is in contact with the ground surface of the high-thickness steel / aluminum composite material, and the length and width are completely aligned, and rivet 8 is used to rivet the head of the assembly, so that a 3mm gap is formed between the aluminum surface of the high-thickness steel / aluminum composite material and the thick aluminum plate with cuboid aluminum blocks, to obtain the high-thickness steel / aluminum composite material assembly 11.
[0043] S3, rapid heating of the core of the billet: The thick steel / aluminum composite billet 11 from step S2 is placed into a specific heating furnace body 12, so that the high-temperature gas from the heat pump 10 flows through the gap between the thick aluminum plate with the large thickness ratio steel / aluminum composite material and the billet along the width direction. The heating time is 40 minutes and the high-temperature gas temperature is 530℃.
[0044] S4, centering and hot pressing: The assembled billet heated in step S3 is centered and held using centering device 13, and then pressure-pressed using pinch roller 14 (the pressure applied by pinch roller 14 is calculated to be 4.8KN), so that the gap between the steel / aluminum composite material with large thickness ratio and the thick aluminum plate with rectangular aluminum block is reduced, forming a billet with small gaps.
[0045] S5, Rolling and Forming of Thick Steel / Aluminum Composite Plates: The micro-void billet obtained in step S4 is fed into rolling mill 15 (No. 2) and rolled at a reduction rate of 40%. After straightening and cutting, thick steel / aluminum composite materials are prepared. Mechanical property tests were conducted on the composite material samples using methods derived from GB / T 6396-2008 "Test Methods for Mechanical and Technological Properties of Composite Steel Plates". The results showed that its shear strength reached 75.2 MPa and its bond strength reached 140.24 MPa.
[0046] Comparative Example 1 The thick steel plate used in this comparative example is Q235B steel (length × width × height is 200mm × 100mm × 20mm), the thin aluminum plate is 1060 aluminum (length × width × height is 200mm × 100mm × 1mm), and the thick aluminum plate is 5083 aluminum (length × width × height is 200mm × 100mm × 20mm).
[0047] A method for rolling thick steel / aluminum composite materials, comprising the following steps: S1, Preparation of high-thickness steel / aluminum composite material: Prepare 1060 thin aluminum plate 3 and remove oil and oxide film from its surface. Use a wire brush to roughen the surface of the 1060 thin aluminum plate 3 to be composited. The surface roughness after grinding is Ra12.5. Prepare Q235B thick steel plate 1 and remove oil and oxide film from its surface. Use a diamond to roughen the surface of the Q235B thick steel plate to be composited. The surface roughness after grinding is Ra25. The roughened 1060 thin aluminum plate 3 and Q235B thick steel plate 1 are placed in a conventional heating furnace 4 and heated to 200°C. The composite is rolled with a 10% reduction rate through a rolling mill, and then straightened and cut to obtain a steel / aluminum composite material with a large thickness ratio.
[0048] S2, Thick steel / aluminum composite preform: Remove oil and oxide film from the aluminum side of the thick steel / aluminum composite material obtained in step S1, and roughen it with a wire brush to a surface roughness of Ra12.5, then let it stand for later use; Take a thick aluminum plate 1 with the same length and width as the thick steel / aluminum composite material prepared in S1, roughen it with a wire brush to a surface roughness of Ra12.5, then let it stand for later use; Assemble the thick steel / aluminum composite material with the thick aluminum plate, so that the thick aluminum plate is in contact with the roughened surface of the thick steel / aluminum composite material, and the length and width are completely aligned, and rivet the head of the preform with rivets 8 to obtain the thick steel / aluminum composite material preform 11.
[0049] S3, Billet Heating: Place the thick steel / aluminum composite billet 11 from step S2 into a conventional heating furnace 4 and heat it to 500℃ for 60 minutes.
[0050] S4, Centering and Hot Pressing: The billet heated in step S3 is centered and held using centering device 13, and then pressure-pressed using pinch roller 14. The pressure applied by pinch roller 14 is 1.2kN, to obtain the hot-pressed billet.
[0051] S5, Rolling and Forming of Thick Steel / Aluminum Composite Plate: The hot-pressed billet obtained in step S4 is fed into rolling mill 15 (No. 2) and rolled at a reduction rate of 25%. After straightening and cutting, a thick steel / aluminum composite material is prepared. Mechanical property tests were conducted on the composite material sample using methods derived from GB / T 6396-2008 "Test Methods for Mechanical and Technological Properties of Composite Steel Plates". The results showed that its shear strength reached 52.4 MPa and its bond strength reached 98.3 MPa. Compared with Example 1, both its shear strength and bond strength were significantly reduced.
[0052] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. A method of core rapid heating rolling of large thickness steel / aluminum composite material, characterized in that, Includes the following steps: The surfaces of the thick steel plate and the thin aluminum plate to be composited are ground separately, then heated to 100-300℃, and rolled once to obtain a high-thickness steel / aluminum composite material. The aluminum side of the high-thickness steel / aluminum composite material is ground to obtain billet 1, which is ready for use. A cuboid aluminum block of the same material and thickness as the thick aluminum plate is welded to the surface of the thick aluminum plate to be composited, and the side with the welded cuboid aluminum block is ground to obtain billet 2, which is ready for use. The length and width of billet 1 and billet 2 are completely aligned and fixed to obtain a high-thickness steel / aluminum composite material assembly billet. The high-temperature gas at 450-530℃ is passed through the gap between billet 1 and billet 2 to heat the high-thickness steel / aluminum composite material assembly billet for 10-40 minutes, and then pinch rolls are used to reduce the gap between billet 1 and billet 2. Finally, the high-thickness steel / aluminum composite material assembly billet after pinch rolls is rolled a second time to obtain the high-thickness steel / aluminum composite material. The thickness of the thick steel plate is ≥20mm; the thickness of the thin aluminum plate is 1-6mm; the thickness of the thick aluminum plate is ≥20mm. The pressure of the pinch roller Where k is a coefficient, ranging from 1.3 to 2; σ is the deformation resistance of the cuboid aluminum block, MPa; b is the width of the cuboid aluminum block, mm; and l is the length of the cuboid aluminum block, mm.
2. The method for rapid heating and rolling of thick steel / aluminum composite materials in the core according to claim 1, characterized in that, The thick steel plate is selected from carbon steel or alloy steel; the thin aluminum plate and the thick aluminum plate are respectively selected from 1-series, 2-series, 3-series, 5-series, 6-series or 7-series aluminum alloys.
3. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The surface roughness of the composite surface of the thick steel plate after grinding is Ra25.
4. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The surface roughness of the composite surface of the thin aluminum plate after polishing is Ra12.
5.
5. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The reduction rate of the single rolling process is 10% to 20%.
6. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The roughness of the blank 1 after polishing is Ra12.
5.
7. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The rectangular aluminum block has a length of 2-4 mm and a width of 1-2 mm.
8. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The rectangular aluminum blocks are placed at intervals of 0.5m along the length of the thick aluminum plate, with at least two rows placed.
9. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The roughness of the blank 2 after polishing is Ra12.
5.
10. The method for rapidly heating and rolling a thick steel / aluminum composite material in the core according to claim 1, characterized in that, The reduction rate of the secondary rolling is 15% to 40%.