Aluminum-tin steel clad plate and method for manufacturing the same

Abstract

The application discloses an aluminum-tin steel composite plate and a preparation method thereof, and belongs to the technical field of alloy materials. The preparation method of the aluminum-tin steel composite plate is as follows: a base steel plate and an aluminum-tin alloy plate are stacked and completely aligned according to a surface to be compounded, wherein the surface of the aluminum-tin alloy plate away from the base steel plate contains an aluminum-containing light metal protective layer, then explosives are uniformly laid on the surface of the aluminum-containing light metal protective layer of the aluminum-tin alloy plate away from the base steel plate, and explosion compounding is carried out by detonating the explosives to obtain an explosion composite plate containing a protective layer; and the explosion composite plate containing the protective layer is shaped and the protective layer is removed, and the aluminum-tin steel composite plate is obtained. The aluminum-tin steel composite plate prepared by the method has high strength and good toughness, and has excellent friction-reducing property, heat conductivity and corrosion resistance; the preparation method is simple, the cost is low, and the method is suitable for industrial production.

Description

Technical Field

[0001] This invention relates to an aluminum-tin-steel composite plate and its preparation method, belonging to the field of alloy material technology. Background Technology

[0002] As ship engines develop towards larger size, higher power, and lower energy consumption, higher requirements are placed on the comprehensive performance of bearing materials. The existing bearing raw materials are mainly prepared by centrifugal casting, which involves covering the surface of steel and other base materials with a layer of tin-based alloy through centrifugal force. This process is mature and has relatively low production costs, which can meet the bearing needs under normal working conditions, but there are also obvious problems: (1) Insufficient interface bonding strength. The composite interface formed by centrifugal casting is a mechanical bond with low bonding strength. Under the harsh working conditions of long-term high load and high speed of ship engines, the tin-based alloy layer is prone to peeling and delamination, which directly leads to bearing failure; (2) Many internal defects. During the casting process, defects such as porosity, inclusions, and shrinkage cavities are easily generated. These defects will reduce the overall mechanical properties and corrosion resistance of the bearing and shorten its service life; (3) Single material properties. Although the friction reduction performance is excellent when using tin-based alloy alone, the strength is low and it is easy to deform and break when subjected to large loads; Steel alone has high strength and toughness, but poor friction reduction performance, which will aggravate the wear between the bearing and the journal and affect the overall life of the engine.

[0003] Therefore, it is of great significance to develop a new process for aluminum-tin-steel composite materials that combines high strength, high bonding strength and excellent friction reduction properties, in order to overcome the defects of existing bearing materials and manufacturing processes and meet the high-performance requirements of marine engines for bearing raw materials. Summary of the Invention

[0004] To address the problems existing in the prior art, the first objective of this invention is to provide a high-performance aluminum-tin-steel composite plate. This aluminum-tin-steel composite plate has high strength and good toughness, while also possessing excellent friction-reducing properties, thermal conductivity, and corrosion resistance.

[0005] The second objective of this invention is to provide a method for preparing an aluminum-tin-steel composite plate. This method is simple, low-cost, and suitable for industrial production.

[0006] To achieve the above-mentioned technical objectives, this invention provides a method for preparing an aluminum-tin-steel composite plate. The method involves stacking a base steel plate and an aluminum-tin alloy plate, aligning them according to the surfaces to be laminated until the edge deviation is ≤1mm. The surface of the aluminum-tin alloy plate away from the base steel plate contains an aluminum-containing light metal protective layer. Explosives are then uniformly laid on the surface of the aluminum-tin alloy plate away from the base steel plate using the aluminum-containing light metal protective layer. The explosive is then detonated to perform an explosive composite plate with a protective layer. The explosive composite plate with the protective layer is obtained by shaping and removing the protective layer. The interlayer gap between each plate layer is 0.5~2mm, the thickness of the explosive is 1~4 times the thickness of the aluminum-tin alloy plate, the detonation velocity is 1900~2500m / s, the detonation pressure is 2~5GPa, and the detonation time is 10~50μs.

[0007] This invention utilizes a low-melting-point aluminum-containing lightweight metal layer as a protective layer for the explosive bonding of aluminum-tin steel, effectively protecting the surface properties of the aluminum-tin alloy. Simultaneously, by controlling the explosion process parameters, an aluminum-tin steel composite plate with excellent overall performance is obtained. The use of ceramic gaskets ensures uniform spacing between the layers, providing space for plastic deformation of the material during explosion. Controlling the detonation pressure to 2-5 GPa and the explosion time to 10-50 μs ensures that each layer undergoes plastic flow and metallurgical bonding under instantaneous high pressure, while preventing excessive pressure from causing material tearing or uneven thickness.

[0008] Among them, the low-melting-point aluminum-containing light metal layer, as a protective layer for aluminum-tin-steel explosion composites, has the following advantages and functions:

[0009] Thermal buffering effect: The aluminum-containing light metal layer has a low melting point. During the explosive composite process, it melts first to absorb some of the heat, which reduces the thermal shock of the aluminum-tin alloy layer at high temperature and prevents changes in its structure or deterioration in its performance.

[0010] Surface protection: Under the action of an explosive shock wave, the aluminum-containing light metal protective layer can act as a sacrificial layer to effectively prevent the aluminum-tin alloy surface from being oxidized, contaminated or mechanically damaged;

[0011] Easy to remove: The aluminum-containing light metal protective layer can be easily removed after an explosion by mechanical processing or chemical corrosion without damaging the surface of the aluminum-tin alloy layer, ensuring the surface quality and dimensional accuracy of the final product.

[0012] As a preferred embodiment, during the application of the emulsion explosive, in the area 20-50mm from the outermost edge of the aluminum-containing light metal protective layer, a wedge-shaped filling method is used to thicken the emulsion explosive, gradually increasing the thickness from the inside out, with an additional thickness of 0.5-1mm. This edge-thickening method avoids the problem of insufficient bonding at the edges due to insufficient energy.

[0013] As a preferred embodiment, the explosive is an expanded ammonium nitrate explosive with a density of 0.9~1.3 g / cm³. This type of explosive has stable energy release, good plastic deformation effect, and can effectively avoid excessive material damage.

[0014] As a preferred embodiment, the explosive composite is detonated using a detonating cord, which is positioned along the central axis of the explosive surface and has a detonator at one end. Alternatively, multi-point synchronous detonation can be used instead of central detonation of the detonating cord, with the detonation points evenly distributed across the explosive surface to ensure more uniform energy distribution. This method is suitable for the fabrication of composite plates with larger dimensions (width ≥ 1000 mm, length ≥ 2500 mm).

[0015] As a preferred solution, replenishment points are set at the center and corners of the aluminum-containing lightweight metal protective layer surface of the aluminum-tin alloy plate. The amount of replenishment explosive is 1.2 to 1.5 times the amount of explosive per unit area in the corresponding region. The replenishment points are formed by drilling and embedding or by surface-applying replenishment blocks. The drilling depth is half the thickness of the emulsion explosive layer, and the replenishment block size is 20×20×5mm, with the same explosive amount as the drilled replenishment. The use of replenishment points can solve the problem of uneven bonding strength during the explosive bonding process, ensuring consistent bonding quality between the edges and the center of the composite plate.

[0016] As a preferred embodiment, the thickness of the base steel plate is 8~25mm, more preferably 10~20mm, and the roughness Ra is 3.2~6.3μm. The base steel plate can be low-carbon steel, alloy steel, stainless steel, etc.

[0017] As a preferred embodiment, the thickness of the aluminum-tin alloy plate is 0.8~6mm, more preferably 1~5mm, wherein the mass content percentage of aluminum to tin is 55~75%:25~45%, more preferably 60~70%:30~40%. The precise proportion of the aluminum-tin alloy composition, compared to traditional tin-based alloys, ensures reduced friction while improving the alloy's strength, thus avoiding deformation and breakage.

[0018] As a preferred embodiment, the thickness of the aluminum-containing light metal protective layer is 0.8~2.5mm, more preferably 1~2mm. The aluminum-containing light metal protective layer is a pure aluminum protective layer or a magnesium-aluminum protective layer.

[0019] As a preferred option, the aluminum-tin alloy sheet is prepared by cold rolling a composite process to laminate an aluminum-containing light metal protective layer onto each of its two surfaces. Laminates both surfaces with this layer, which facilitates the transportation and storage of the aluminum-tin alloy sheet. If transportation and storage are not a concern, a layer of aluminum-containing light metal can be laminated onto only one surface of the aluminum-tin alloy sheet.

[0020] As a preferred embodiment, a copper plate or copper alloy plate is added between the base steel plate and the aluminum-tin alloy plate. The copper plate or copper alloy plate has a thickness of 0.2~1mm and a surface roughness Ra of 1.6~3.2μm. By adding a copper transition layer to optimize the interface bonding, a precise match between strength and friction reduction performance is achieved.

[0021] As a preferred option, when both surfaces of the aluminum-tin alloy plate contain an aluminum-containing light metal protective layer, the protective layer on one of the surfaces is removed, and the unprotected surface faces the base steel plate.

[0022] The present invention also provides an aluminum-tin-steel composite plate, which is prepared by the above method.

[0023] As a preferred embodiment, the aluminum-tin-steel composite plate comprises a steel base layer and an aluminum-tin alloy layer, or comprises a steel base layer, a copper transition intermediate layer, and an aluminum-tin alloy outer layer.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] (1) The aluminum-tin-steel composite plate prepared by the present invention has high strength and toughness, good wear resistance, excellent mechanical properties and friction reduction properties, strong stability, long service life, and the service life of the product is 2 to 3 times longer than that of traditional bearings. It can be adapted to the bearing requirements of ship engines with different power and different working conditions.

[0026] (2) By using specific explosive composite process conditions, defects such as porosity and inclusions in the casting process are effectively avoided. The UT test grade I pass rate is over 98%. Moreover, the preparation method is simple, low cost, and highly controllable, making it suitable for industrial application. Attached Figure Description

[0027] Figure 1 The image shows the microstructure of the aluminum-tin-steel composite plate prepared in Example 1.

[0028] Figure 2 The image shows the microstructure of the aluminum-tin-steel composite plate prepared in Example 2.

[0029] Figure 3 This is a microstructure diagram of the aluminum-tin-steel composite plate prepared in Example 3. Detailed Implementation

[0030] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1

[0032] (1) Base steel treatment: 12mm thick 20# steel plate is used as the base steel plate. The surface is treated with shot blasting machine to remove oxide scale, rust and oil stains. Then the surface is sanded with sandpaper until the roughness Ra is 4.5μm. Finally, it is wiped clean with anhydrous ethanol and allowed to air dry naturally.

[0033] (2) Aluminum-tin alloy plate processing: Aluminum-tin alloy plate with a thickness of 3mm, aluminum content of 65wt%, and tin content of 35wt% is laminated with a 1.5mm thick pure aluminum protective layer on both the upper and lower surfaces of the aluminum-tin alloy through a cold rolling composite process to form a "pure aluminum-aluminum-tin alloy-pure aluminum" composite plate. Then, before use, the protective layer on one of the surfaces is removed by grinding, and the surface roughness Ra measured during grinding is 4μm, resulting in an aluminum-tin alloy plate with a pure aluminum protective layer on one of the surfaces.

[0034] (3) Explosive composite: The base steel plate and aluminum-tin alloy plate are stacked vertically in sequence and aligned until the edge deviation is ≤1mm. The surface of the aluminum-tin alloy plate without protective layer faces the base steel plate, while the surface with pure aluminum protective layer is away from the base steel plate. Ceramic gaskets are placed between the plates to support and control the interlayer gap to be 1.2mm. Then, expanded ammonium nitrate explosive is evenly spread on the surface of the aluminum-tin alloy plate with pure aluminum protective layer. The explosive thickness is 6.6mm. In the edge area 20-50mm away from the outermost edge of the plate, the explosive is thickened by 0.8mm using a wedge filling method. In addition, replenishment points are set in the center area and four corners of the plate. The replenishment amount is 1.3 times the amount of explosive per unit area of ​​the corresponding area.

[0035] (4) Detonation is initiated using a detonating cord. The detonating cord is positioned at the central axis of the explosive surface, with a detonator at one end to ignite the explosive for detonation and composite formation. The detonation velocity is 2300 m / s, the detonation pressure is 3 GPa, and the detonation time is 30 μs. This yields a composite plate with a protective layer. The plate is then straightened using a straightening machine to ensure a flatness error ≤ 0.3 mm / m. Incompletely bonded edges are removed, and the protective layer is then removed to obtain an aluminum-tin-steel composite plate. The relevant properties of this aluminum-tin-steel composite plate are tested, including:

[0036] Bond strength: Shear test was conducted according to GB / T 6396-2008 standard, and the result was 69 MPa;

[0037] Friction reduction performance: The friction and wear test was conducted according to GB / T 12444-2006, with a friction coefficient of 0.08 and a wear amount of 0.01 mm³.

[0038] Figure 1 The image shows the microstructure (metallographic image) of the aluminum-tin-steel composite plate prepared under the conditions of this embodiment. It can be seen from the image that the interface is well bonded and there are no pores or inclusions.

[0039] Example 2

[0040] (1) Base steel treatment: A steel plate with a thickness of 15mm and a carbon content of 0.18% is used as the base steel plate. The surface is treated by shot blasting to remove oxide scale, rust and oil stains. Then, the surface is sanded with sandpaper until the roughness Ra is 5.0μm. Finally, it is wiped clean with anhydrous ethanol and allowed to air dry naturally.

[0041] (2) Copper treatment of transition layer: Use a wire brush to remove the oxide film on the surface of the copper plate with a thickness of 0.5mm, then use sandpaper to finely polish it until the roughness Ra is 2.5μm, clean it with anhydrous ethanol and then air dry it to ensure that the surface is clean and free of oxidation.

[0042] (3) Aluminum-tin alloy plate treatment: Aluminum-tin alloy plate with a thickness of 4mm, aluminum content of 60wt% and tin content of 40wt% is laminated with a 1.2mm thick magnesium-aluminum alloy protective layer on the upper and lower surfaces of the aluminum-tin alloy through a cold rolling composite process to form an aluminum-tin alloy composite plate with a magnesium-aluminum alloy protective layer on the surface. Then, before use, the protective layer on one of the surfaces is removed by grinding. The surface roughness Ra of the surface is measured to be 4μm, and an aluminum-tin alloy plate with a magnesium-aluminum alloy protective layer on one of the surfaces is obtained.

[0043] (4) Explosive composite: The base steel plate, transition copper plate, and aluminum-tin alloy composite plate are stacked vertically and aligned in sequence, with the interlayer gap controlled at 1.5 mm. The surface of the aluminum-tin alloy plate without a protective layer faces the copper plate, while the surface containing the magnesium-aluminum alloy protective layer is away from the copper plate. Then, expanded ammonium nitrate explosive is evenly laid on the surface of the magnesium-aluminum alloy protective layer of the aluminum-tin alloy plate with a thickness of 12 mm. In the edge area 20-50 mm away from the outermost edge of the plate, the explosive is thickened by 1 mm using a wedge filling method. In addition, replenishment points are set in the center area and four corners of the plate, with the replenishment amount being 1.4 times the amount of explosive per unit area of ​​the corresponding area.

[0044] (4) Detonation is initiated using a detonating cord. The detonating cord is positioned at the central axis of the explosive surface, with a detonator at one end to detonate the explosive for detonation and composite formation. The detonation velocity is 2100 m / s, the detonation pressure is 4.0 GPa, and the detonation time is 40 μs. This yields a composite plate with a protective layer. The plate is then straightened using a straightening machine to ensure a flatness error ≤ 0.3 mm / m. Incompletely bonded edges are removed, and the protective layer is then removed to obtain an aluminum-tin-steel composite plate. The relevant properties of this aluminum-tin-steel composite plate are tested using the same method as in Example 1.

[0045] Bond strength: Shear strength is 72 MPa;

[0046] Friction reduction performance: coefficient of friction 0.1, wear amount 0.015mm³.

[0047] Figure 2 The image shows the microstructure of the aluminum-tin-steel composite plate prepared under the conditions of this embodiment. As can be seen from the image, the interface is well bonded, exhibiting a wavy metallurgical bond, and there is no obvious diffusion layer between the copper layer and the aluminum-tin alloy layer.

[0048] Example 3

[0049] (1) Base steel treatment: A steel plate with a thickness of 20mm and a carbon content of 0.15% is used as the base steel plate. The surface is treated by shot blasting to remove oxide scale, rust and oil stains. Then the surface is sanded with sandpaper until the roughness Ra is 6μm. Finally, it is wiped clean with anhydrous ethanol and allowed to air dry naturally.

[0050] (2) Aluminum-tin alloy plate processing: A 2mm thick pure aluminum protective layer is laminated on one surface of the aluminum-tin alloy plate with a thickness of 5mm, an aluminum content of 70wt%, and a tin content of 30wt% through a cold rolling composite process, forming an aluminum-tin alloy plate with a pure aluminum protective layer on one surface.

[0051] (3) Explosive bonding: The base steel plate and aluminum-tin alloy plate are stacked and aligned in sequence, with the unprotected surface of the aluminum-tin alloy plate facing the base steel plate and the surface containing the pure aluminum protective layer away from the base steel plate. The gap between the plates is controlled at 2.0 mm. Then, expanded ammonium nitrate explosive is evenly laid on the pure aluminum protective layer surface of the aluminum-tin alloy plate with an explosive thickness of 20 mm. In the edge area 20-50 mm away from the outermost edge of the plate, the explosive is thickened by 1.0 mm using a wedge filling method. In addition, replenishment points are set in the center area and four corners of the plate, with the replenishment amount being 1.5 times the amount of explosive per unit area of ​​the corresponding area.

[0052] (4) Detonation is initiated using a detonating cord, which is positioned at the central axis of the explosive surface. A detonator is installed at one end to detonate the explosive for detonation and composite formation. The detonation velocity is 1900 m / s, the detonation pressure is 3.5 GPa, and the detonation time is 50 μs. This yields a composite plate with a protective layer. The plate is then straightened using a straightening machine to ensure a flatness error ≤ 0.3 mm / m. Incompletely bonded edges are removed, and the protective layer is then removed to obtain an aluminum-tin-steel composite plate. The relevant properties of this aluminum-tin-steel composite plate are tested using the same method as in Example 1.

[0053] Bond strength: Shear strength is 62 MPa;

[0054] Friction reduction performance: coefficient of friction 0.12, wear amount 0.02mm³.

[0055] Figure 3 The image shows the microstructure of the aluminum-tin-steel composite plate prepared under the conditions of this embodiment. As can be seen from the image, the interface bonding is good and there are no obvious defects.

[0056] Comparative Example 1

[0057] ECKA Granulate Essen's commercially available aluminum-tin 40 steel composite plate has an aluminum-tin alloy layer with an aluminum content of 60 wt% and a tin content of 40 wt% (the same as the aluminum-tin alloy composition in Example 2), and the base steel plate is 20# steel. The total thickness is similar to that of Example 1. This composite plate is manufactured using a centrifugal casting process, and the interface is mechanically bonded.

[0058] The shear strength of the commercially available composite board was tested according to GB / T 6396-2008, and the result was 32.3 MPa; the friction and wear test was conducted according to GB / T 12444-2006, and the friction coefficient was 0.18 and the wear amount was 0.035 mm³.

[0059] Compared with Examples 1-3 of this invention, the shear strength of the comparative product is less than half that of the product of this invention, and its friction-reducing performance is also significantly worse. It is evident that the aluminum-tin-steel composite plate prepared by this invention is significantly superior to existing commercially available similar products in terms of interfacial bonding strength and friction-reducing performance.

[0060] Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing an aluminum-tin-steel composite plate, characterized in that: The base steel plate and aluminum-tin alloy plate are stacked and aligned according to the surfaces to be composited until the edge deviation is ≤1mm. The surface of the aluminum-tin alloy plate away from the base steel plate contains an aluminum-containing light metal protective layer. Explosives are then evenly laid on the surface of the aluminum-tin alloy plate away from the base steel plate containing the aluminum-containing light metal protective layer. The explosive is detonated to perform explosive composite, resulting in an explosive composite plate with a protective layer. The explosive composite plate with a protective layer is obtained by shaping and removing the protective layer. The interlayer gap between each plate layer is 0.5~2mm, the thickness of the explosive is 1~4 times the thickness of the aluminum-tin alloy plate, the explosion velocity is 1900~2500m / s, the detonation pressure is 2~5GPa, and the explosion time is 10~50μs.

2. The method for preparing an aluminum-tin-steel composite plate according to claim 1, characterized in that: During the laying of the explosives, for the area 20-50mm from the outermost edge of the aluminum-containing light metal protective layer, the explosives are thickened using a wedge-shaped filling method, gradually thickening from the inside out, with a thickness of 0.5-1mm.

3. The method for preparing an aluminum-tin-steel composite plate according to claim 1 or 2, characterized in that: The explosive is an expanded ammonium nitrate explosive.

4. The method for preparing an aluminum-tin-steel composite plate according to claim 1, characterized in that: Addition points are set at the center and corners of the aluminum-containing light metal protective layer surface of the aluminum-tin alloy plate, and the amount of addition is 1.2 to 1.5 times the amount of explosive per unit area of ​​the corresponding region.

5. The method for preparing an aluminum-tin-steel composite plate according to claim 1, characterized in that: The thickness of the base steel plate is 8~25mm, and the roughness Ra is 3.2~6.3μm.

6. The method for preparing an aluminum-tin-steel composite plate according to claim 1, characterized in that: The aluminum-tin alloy plate has a thickness of 0.8~6mm, wherein the mass percentage of aluminum to tin is 55~75%:25~45%; The thickness of the aluminum-containing light metal protective layer is 0.8~2.5mm; the aluminum-containing light metal protective layer is a pure aluminum protective layer or a magnesium-aluminum protective layer.

7. The method for preparing an aluminum-tin-steel composite plate according to claim 1, characterized in that: A copper plate or copper alloy plate is added between the base steel plate and the aluminum-tin alloy plate. The thickness of the copper plate or copper alloy plate is 0.2~1mm and the surface roughness Ra is 1.6~3.2μm.

8. The method for preparing an aluminum-tin-steel composite plate according to claim 1, characterized in that: When both surfaces of an aluminum-tin alloy plate contain a protective layer of aluminum-containing light metal, remove the protective layer from one of the surfaces and turn the unprotected surface toward the base steel plate.

9. An aluminum-tin-steel composite plate, characterized in that: Prepared by the method described in any one of claims 1 to 8.

10. An aluminum-tin-steel composite plate according to claim 9, characterized in that: It may contain a steel base layer and an aluminum-tin alloy layer, or a steel base layer, a copper transition intermediate layer, and an aluminum-tin alloy outer layer.

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