Extrusion device for preparing thickness-controllable ultra-fine grain sheet strip

Abstract

The invention relates to the technical field of metal material processing, in particular to an extrusion device for preparing thickness-controllable ultra-fine grain sheet strips, which comprises a mounting seat, a support frame, a chamfering cutter, a limiting block, a gasket, a cover plate and connecting components among the mounting seat, the support frame, the chamfering cutter, the limiting block, the gasket and the cover plate. Positioning holes are formed in the two sides of the mounting base, and the supporting frame is fixed to the mounting base through the mounting holes and mounting bolts; a tool clamping groove and an outflow groove are formed in the upper end of the supporting frame, a chamfering tool is installed in the tool clamping groove through a first locking hole, a first locking bolt and a first locking nut, the inclination angle of the front tool face of the chamfering tool is 30 degrees, and a first inclined face matched with the limiting block is arranged at the top of the chamfering tool. The inclination angle of the first inclined face is 30 degrees, and the first inclined face extends from the top of the front cutter face to the rear end. The device is used for preparing the metal sheet strips with the ultra-fine grains and has the advantages of being simple in structure, low in cost and capable of preparing the metal sheet strips with different thicknesses.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material processing, and particularly relates to an extrusion device for preparing ultra-fine grained thin strip with controllable thickness. Background Art

[0002] With the continuous progress of industrial technology, the performance requirements for metal materials are becoming increasingly strict. Especially the contradiction between strength and ductility has long troubled the wide application of metal materials. Ultra-fine grained materials (UFG) have become the focus of research because they can significantly improve the mechanical properties of materials such as tensile strength, hardness, and wear resistance. The refinement of grains can significantly increase the number of grain boundaries, thereby improving the strength of the material, reducing stress concentration, and enhancing its deformation ability. At the same time, the refinement of grains also brings the side effect of a significant reduction in ductility, which has become a bottleneck restricting the wide application of ultra-fine grained materials. Therefore, how to improve the strength of metals while maintaining their excellent plasticity and ductility has become a key issue in the research of metal materials.

[0003] To solve this problem, researchers have proposed various severe plastic deformation (SPD) methods, such as equal channel angular pressing (ECAP), accumulative roll bonding (ARB), high-pressure torsion (HPT), etc. Although these methods can significantly refine grains, they usually have some deficiencies. For example, multi-pass processing leads to complex processes, long production cycles, and high costs. At the same time, these methods may cause a significant decrease in the ductility of materials, restricting their application in high-performance materials. With the increasing demand for ultra-fine grained materials, how to prepare high-strength and high-plasticity metal materials through more efficient and low-cost processes has become an important research direction in the field of material processing.

[0004] Large Strain Extrusion Machining (LSEM), as an emerging metal processing technology, combines laser surface treatment and large strain cutting technology. It has received extensive attention because it can significantly refine grains and maintain good surface quality during the single-step forming process. The LSEM process realizes the formation of ultra-fine grained structure of metal materials by introducing laser heating during the cutting process. The laser beam locally heats the metal surface and performs cutting under high strain. At the same time, LSEM effectively controls the temperature distribution in the deformation zone and the thickness of the chip through the design of the restraining block, which plastically deforms the chip. This process can not only significantly improve the mechanical properties of materials but also maintain a certain ductility, solving the contradiction between strength and plasticity of traditional ultra-fine grained materials.

[0005] Although certain progress has been made in the preparation of ultrafine-grained materials by the LSEM process, there are still some technical problems in practical applications, especially in terms of the controllability of strip thickness and the consistency of surface quality. In the current LSEM process during strip production, how to precisely control the thickness of the strip and maintain its surface finish while ensuring grain refinement remains a challenge for technical implementation. At the same time, the design of the restraint block has a crucial impact on the effect of the LSEM process. Existing restraint block designs usually rely on experience for adjustment and lack precise optimization schemes, resulting in difficulties in ensuring the performance and consistency of strips under different material and process conditions.

[0006] To solve these problems, the present invention proposes an extrusion device for preparing ultrafine-grained thin strip with controllable thickness. Based on the LSEM process, through innovative chamfering tool and restraint block designs, it can effectively control the strip thickness and maintain the consistency of grain refinement throughout the preparation process. At the same time, the present invention significantly improves the surface quality and production accuracy of the strip through improved designs. Compared with the prior art, the present invention not only simplifies the implementation process of the LSEM process, reduces production costs, but also provides a more efficient and stable method for preparing ultrafine-grained metal strips, having important engineering application value. Summary of the Invention

[0007] The object of the present invention is to provide an extrusion device for preparing ultrafine-grained thin strip with controllable thickness for preparing metal thin strips with ultrafine grains. The device of the present invention has the characteristics of simple structure, low cost and the ability to prepare metal thin strips with different thicknesses.

[0008] To achieve the above technical objects and reach the above technical effects, the present invention is realized through the following technical solutions:

[0009] An extrusion device for preparing ultrafine-grained thin strip with controllable thickness, comprising:

[0010] A mounting seat, a support frame, a chamfering tool, a restraint block, a gasket, a cover plate and the connecting components therebetween;

[0011] Positioning holes are provided on both sides of the mounting seat, and the support frame is fixed to the mounting seat through mounting holes and mounting bolts;

[0012] A tool clamping groove and an outflow groove are provided at the upper end of the support frame. The chamfering tool is installed in the tool clamping groove through a first locking hole, a first locking bolt and a first locking nut. The rake face inclination angle of the chamfering tool is 30°, and a first inclined surface for cooperating with the restraint block is provided at its top. The inclination angle of the first inclined surface is 30° and extends from the top of the rake face to the rear end;

[0013] The cover plate is fixed to the upper end of the support frame through the third locking holes, third locking bolts and third locking nuts. A limiting block clamping groove is provided on the lower end surface of the cover plate. The limiting block is installed in the limiting block clamping groove through the second locking holes, second locking bolts and second locking nuts. A second inclined surface is provided on the lower surface of the limiting block, which is parallelly coupled with the first inclined surface of the chamfering tool to form a composite shear zone;

[0014] A third inclined surface is provided in the upper end groove of the support frame. The third inclined surface communicates with the outflow groove and is used to guide the material flow;

[0015] The gasket is arranged between the limiting block and the support frame and is used to adjust the distance between the chamfering tool and the limiting block to control the strip thickness.

[0016] Furthermore, the size of the mounting base is 150 mm in length, 170 mm in width and 47.5 mm in height. Positioning holes, mounting grooves and a plurality of mounting holes are provided on its base. The mounting holes are symmetrically distributed along the embedding positions of the mounting base and the support frame.

[0017] Furthermore, a locking bolt mounting groove is provided on the side surface of the support frame. The cross-sectional shape of the outflow groove is rectangular or trapezoidal, and its thickness matches the cutting thickness of the front tool face of the chamfering tool.

[0018] Furthermore, the size of the chamfering tool is 59.8 mm in length, 24 mm in width and 12 mm in height. The distance between the first inclined surface and the second inclined surface is 0.1 - 5 mm, and the distance is adjusted by the thickness or quantity of the gasket.

[0019] Furthermore, the size of the limiting block is 79.8 mm in length, 24 mm in width and 12 mm in height. The coupling area between its second inclined surface and the first inclined surface of the chamfering tool forms a multi-stage gradient shear deformation zone.

[0020] Furthermore, the size of the cover plate is 140 mm in length, 85 mm in width and 24 mm in height. A groove matching the upper end locking step of the support frame is provided on its bottom surface and is locked through the third locking bolts and third locking nuts.

[0021] Furthermore, the inclination angle of the third inclined surface is the same as that of the first inclined surface and the second inclined surface. The synergistic effect of the three guides the material to generate directional plastic flow in the outflow groove.

[0022] Furthermore, the chamfering tool and the limiting block adopt a detachable design, and their installation positions are adjusted through locking bolts and nuts to meet the processing requirements of different materials.

[0023] The beneficial effects of the present invention:

[0024] The present invention is designed based on the double-bevel geometric constraints of the chamfer tool and the limiting block. During the machining process, the material undergoes multi-level gradient shear deformation. The 30° inclination angle of the rake face of the chamfer tool and the 30° inclined plane of the lower surface of the limiting block form a composite shear stress field through spatial coupling, which promotes the severe plastic deformation of metal grains under the dual action of tool cutting and block extrusion. The dislocation density is significantly increased, and a fine sub-grain structure is formed. The 30° inclination angle of the third inclined plane in the support groove further guides the material to flow directionally. This multi-directional shear strategy breaks through the limitations of traditional single-directional deformation, effectively avoids local stress concentration, maintains the continuity of the grain boundary structure while refining the grains to the sub-micron level, and thus improves the material strength while retaining excellent ductility.

[0025] The present invention realizes the precise machining control of metal circular tube materials by the synergistic effect of various components such as the base, support frame, chamfer tool, limiting block, and cover plate. The structural design of the device ensures the stable deformation of the metal material during the machining process, thus avoiding common material waste and uneven machining problems while maintaining high strength. Through reasonable structural configuration, the workpiece to be machined can undergo the dual action of the limiting block and the chamfer tool during the operation process to form a uniform ultrafine grain structure, and complete the entire plastic flow forming process through one machining process, simplifying the traditional machining process. Compared with the traditional method, the present invention not only improves the machining efficiency, but also optimizes the physical properties of the metal sheet, including tensile strength and hardness, and has simple operation, is applicable to the machining of different types of metal materials, and has broad industrial application prospects.

[0026] The formation of the controllable-thickness ultrafine grain material prepared by the device of the present invention mainly relies on the coupling effect of shear, extrusion, extrusion, and friction between the material to be machined, the chamfer tool, the limiting block, and the outflow channel. The material separated from the workpiece to be machined is cut by the chamfer tool, and then extruded through the outflow channel to form an ultrafine grain strip by cooperating with the limiting block. In addition, after the metal sheet is sheared and extruded, its yield strength and microhardness will increase compared with those before machining, and at the same time, it can still maintain a considerable ductility.

[0027] The mounting base, support frame, chamfer tool, limiting block, gasket, and cover plate of the device of the present invention are all very convenient and easy to install. In addition, the present invention can also prepare metal sheets with different thicknesses according to production needs, which can be obtained by replacing circular tube workpieces with different thicknesses, gaskets with different sizes, and chamfer tools with different parameters, which is very convenient. The device can be applied to a wide range of machining materials, such as ductile metals such as bulk copper, aluminum, iron, and steel.

[0028] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. Brief Description of the Drawings

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 It is an exploded split schematic diagram of the overall structure of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0031] Figure 2 It is a schematic diagram of the overall structure of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0032] Figure 3 It is a schematic diagram of the structure of the mounting seat of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0033] Figure 4 It is a schematic diagram of the structure of the support frame of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0034] Figure 5 It is a schematic diagram of the structure of the chamfering tool of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0035] Figure 6 It is a schematic diagram of the structure of the limiting block of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0036] Figure 7 It is a schematic diagram of the structure of the gasket of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0037] Figure 8 It is a schematic diagram of the structure of the cover plate of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0038] Figure 9 It is a schematic diagram of the structure of the processed workpiece of an extrusion device for preparing an ultrafine-grained thin plate strip with controllable thickness according to the present invention;

[0039] In the figure: 1, mounting base; 2, support frame; 3, chamfering tool; 4, limiting block; 5, gasket; 6, cover plate; 7, positioning hole; 8, mounting groove; 9, mounting hole; 10, mounting bolt; 11, mounting nut; 12, first locking hole; 13, first locking bolt; 14, first locking nut; 15, locking bolt mounting groove; 16, tool clamping groove; 17, tool mounting hole; 18, rake face; 19, second locking hole; 20, second locking bolt; 21, second locking nut; 22, limiting block mounting hole; 23, limiting block clamping groove; 24, third locking hole; 25, third locking bolt; 26, third locking nut; 27, locking step; 28, first inclined surface; 29, second inclined surface; 30, third inclined surface; 31, outflow groove. Detailed implementation manner

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0041] Embodiment 1

[0042] An extrusion device for preparing an ultrafine-grained thin strip with a controllable thickness according to this embodiment includes a mounting base 1, a support frame 2, a chamfering tool 3, a limiting block 4, a gasket 5, a cover plate 6, a positioning hole 7, a mounting groove 8, a mounting hole 9, a mounting bolt 10, a mounting nut 11, a first locking hole 12, a first locking bolt 13, a first locking nut 14, a locking bolt mounting groove 15, a tool clamping groove 16, a tool mounting hole 17, a rake face 18, a second locking hole 19, a second locking bolt 20, a second locking nut 21, a limiting block mounting hole 22, a limiting block clamping groove 23, a third locking hole 24, a third locking bolt 25, a third locking nut 26, a locking step 27, a first inclined surface 28, a second inclined surface 29, a third inclined surface 30, and an outflow groove 31. The two positioning holes 7 are through-hole structures and are located on both sides of the mounting base 1. The support frame 2 is tightly embedded in the mounting base 1. The plurality of mounting holes 9 are through-hole structures and are located at the corresponding embedding positions of the mounting base 1 and the support frame 2. The bolt mounting groove 15 is a groove structure and is located on the outer end face of the support frame 2. The third inclined surface 30 is located in the upper-end groove of the support frame 2. The outflow groove 31 is located behind the third inclined surface 30. The tool clamping groove 16 is a groove structure and is located at the upper end of the support frame 2. The chamfering tool 3 is installed in the tool clamping groove 16 through the first locking hole 12. The first inclined surface 28 is located on the upper end face of the chamfering tool 3. The limiting block clamping groove 23 is a groove structure and is located on the lower end face of the cover plate 6. The limiting block 4 is installed in the limiting block clamping groove 23 through the second locking hole 19 and is located directly above the chamfering tool 3. The second inclined surface 29 is located at the lower end of the limiting block 4 and is directly above the first inclined surface 28. The plurality of third locking holes 24 are through-hole structures and are located in the embedding positions of the cover plate 6 and the support frame 2. The bottom surface of the cover plate 6 is provided with a groove that cooperates with the locking step 27 at the upper end of the support frame 2 and is locked through the third locking hole 24, the third locking bolt 25, and the third locking nut 26. The gasket 5 is located between the limiting block 4 and the support frame 2.

[0043] The size of the mounting base 1 is 150 mm in length, 170 mm in width, and 47.5 mm in height. The base design includes multiple holes and grooves. The upper-end groove of the support frame 2 is provided with a tool clamping groove and an outflow channel, and the side is provided with a bolt mounting groove. The size of the chamfering tool 3 is 59.8 mm in length, 24 mm in width, and 12 mm in height. The inclination angle of the rake face is 30°, and the rear end is provided with a 30° inclined surface. The size of the limiting block 4 is 79.8 mm in length, 24 mm in width, and 12 mm in height. The lower surface is provided with a 30° inclined surface inside. The size of the cover plate 6 is 140 mm in length, 85 mm in width, and 24 mm in height. The cover plate is provided with multiple holes and grooves inside.

[0044] For the purpose of being able to prepare an extrusion device for thin metal sheets with ultrafine grains of controllable thickness, the present invention makes full use of the deformation properties of metal materials. First, the extrusion device is fixed on an ordinary horizontal lathe with a horizontal layout, and the workpiece to be processed is fixed in the lathe spindle. The cutting speed during the processing is controlled by the rotation speed of the lathe spindle, and the cutting function is realized by the chamfering tool 3. The extrusion function of the workpiece and the control of the geometric morphology of the extruded strip are realized through the cooperation between the limiting block 4 and the chamfering tool 3. Under the combined action of the rake face 18 of the chamfering tool 3 and the limiting block 4, the workpiece material with the thickness to be cut is restricted when flowing along the chip flow direction, forming an extruded strip of a certain thickness. The thickness to be cut and the thickness of the extruded strip can be realized by adjusting the relative positions of the limiting block 4 and the chamfering tool 3, and the relative positions of the chamfering tool 3 and the limiting block 4 are controlled by adjusting the number of shims 5 and using shims 5 with different thicknesses.

[0045] The formation of the thin metal sheet with ultrafine grains of controllable thickness in the present invention mainly relies on the coupled action of shearing, extrusion, and extrusion of the material to be processed with the chamfering tool 3, the limiting block 4, and the extrusion channel. The material separated from the workpiece to be processed enters between the limiting block 4 and the chamfering tool 3 and flows out through the first inclined surface 28, the third inclined surface 30, and the outflow groove 31. In addition, after being extruded, the yield strength and microhardness of the thin metal sheet will increase compared with those before processing, and at the same time, it can still maintain a considerable ductility.

[0046] In addition, according to the production needs, the present invention can replace the round tube workpieces with different thicknesses to prepare thin metal sheets with different extrusion thicknesses. Different geometric parameters of thin metal sheets can also be prepared by replacing the chamfering tool 3 with different chamfering angles, and the geometric parameters of the chamfering tool 3 can be changed by replacing different chamfering tools 3. Moreover, the chamfering tool 3 and the support frame 2 in this device are assembled separately, and different tools can be replaced according to requirements; the processing material range applicable to this device is wide, and it can be ductile metals such as tubular copper, aluminum, iron, and steel.

[0047] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, according to the content of this specification, many modifications and changes can be made. The present specification selects and specifically describes these embodiments to better explain the principle and practical application of the present invention, so that those skilled in the art in the relevant technical field can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. An extrusion device for preparing ultrafine-grained thin sheet strips with controllable thickness, characterized in that, Comprising: A mounting base (1), a support frame (2), a chamfering tool (3), a limiting block (4), a gasket (5), a cover plate (6), and connection components therebetween; Positioning holes (7) are provided on both sides of the mounting base (1), and the support frame (2) is fixed to the mounting base (1) through mounting holes (9) and mounting bolts (10); A tool clamping groove (16) and an outflow groove (31) are provided at the upper end of the support frame (2). The chamfering tool (3) is installed in the tool clamping groove (16) through a first locking hole (12), a first locking bolt (13), and a first locking nut (14). The inclination angle of the front tool face (18) of the chamfering tool (3) is 30°. A first inclined surface (28) that cooperates with the limiting block (4) is provided at the top thereof. The inclination angle of the first inclined surface (28) is 30° and extends from the top of the front tool face (18) to the rear end; The cover plate (6) is fixed to the upper end of the support frame (2) through a third locking hole (24), a third locking bolt (25), and a third locking nut (26). A limiting block clamping groove (23) is provided on the lower end surface of the cover plate (6). The limiting block (4) is installed in the limiting block clamping groove (23) through a second locking hole (19), a second locking bolt (20), and a second locking nut (21). A second inclined surface (29) is provided on the lower surface of the limiting block (4), which is parallelly coupled with the first inclined surface (28) of the chamfering tool (3) to form a composite shear zone; A third inclined surface (30) is provided in the upper end groove of the support frame (2). The third inclined surface (30) is communicated with the outflow groove (31) for guiding the material flow; The gasket (5) is arranged between the limiting block (4) and the support frame (2) for adjusting the distance between the chamfering tool (3) and the limiting block (4) to control the strip thickness.

2. The extrusion device according to claim 1, characterized in that, The mounting base (1) has dimensions of 150 mm in length, 170 mm in width, and 47.5 mm in height. Its base is provided with positioning holes (7), mounting grooves (8), and a plurality of mounting holes (9). The mounting holes (9) are symmetrically distributed along the embedding positions of the mounting base (1) and the support frame (2).

3. The extrusion device according to claim 1, characterized in that, A locking bolt mounting groove (15) is provided on the side surface of the support frame (2). The cross-sectional shape of the outflow groove (31) is rectangular or trapezoidal, and its thickness matches the cutting thickness of the front tool face (18) of the chamfering tool (3).

4. The extrusion device according to claim 1, wherein The chamfering tool (3) has dimensions of 59.8 mm in length, 24 mm in width, and 12 mm in height. The distance between the first inclined surface (28) and the second inclined surface (29) is 0.1 - 5 mm, and the distance is adjusted by the thickness or quantity of the gasket (5).

5. The extrusion device according to claim 1, wherein, The limiting block (4) has dimensions of 79.8 mm in length, 24 mm in width, and 12 mm in height. The coupling area between its second inclined surface (29) and the first inclined surface (28) of the chamfering tool (3) forms a multi-stage gradient shear deformation zone.

6. The extrusion device according to claim 1, characterized in that, The cover plate (6) has dimensions of 140 mm in length, 85 mm in width, and 24 mm in height. A groove that cooperates with the upper end locking step (27) of the support frame (2) is provided on its bottom surface and is locked through a third locking bolt (25) and a third locking nut (26).

7. The extrusion device according to claim 1, characterized in that, The inclination angle of the third inclined surface (30) is the same as that of the first inclined surface (28) and the second inclined surface (29), and the synergistic effect of the three guides the material to generate directional plastic flow in the outflow groove (31).

8. The extrusion device according to claim 1, wherein, The chamfering tool (3) and the limiting block (4) are designed to be detachable, and their installation positions are adjusted by lock bolts and nuts to meet the processing requirements of different materials.

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