A grooved stationary shoulder friction stir processing tool

Abstract

The present invention discloses a groove-type static shoulder friction stirring processing tool, comprising a stirring head, a fixed sleeve, a thrust ball bearing, a groove-type static shoulder device and a cushion block assembly, wherein one end of the stirring head is provided with a stirring needle, the stirring head can be connected to the main shaft of the friction stirring processing equipment, the fixed sleeve can be connected to the main shaft box of the friction stirring processing equipment, and the thrust ball bearing is connected to the groove-type static shoulder device, so that the groove-type static shoulder device can be twisted according to the contour of the workpiece during the processing. The groove-type static shoulder device and the cushion block assembly cooperate to form an effective clamping effect on the side of the workpiece, and the stirring needle can process the processing area to obtain a uniform and dense organizational structure; the friction stirring processing of a local or small-area workpiece can be realized without complex tooling clamping, and the spacing between the two side cushion blocks can be adjusted, thereby achieving the purpose of adjusting the side pressure of the workpiece and eliminating the tunnel hole defects formed due to insufficient pressure.

Description

Technical Field

[0001] The invention relates to the technical field of friction stirring processing equipment and peripheral supporting facilities thereof, in particular to a groove-type stationary shoulder friction stirring processing tool. Background Art

[0002] Friction stir welding (FSW) is a solid-phase joining technology invented in 1991, which is particularly suitable for welding low-melting-point alloys such as aluminum and magnesium. Friction stir processing (FSP) is a plastic processing technology developed on the basis of FSW. Its basic principle is similar to FSW. A high-speed rotating stirring needle is inserted into the material. The strong stirring action of the stirring head causes the processed material to undergo severe plastic deformation, mixing and crushing, thereby achieving the densification, homogenization and refinement of the material microstructure, thereby improving the material performance. At present, friction stir processing technology has achieved good results in the preparation of fine-grained / ultra-fine-grained materials and surface / bulk composite materials, microstructure modification of heterogeneous materials, local hardening / defect repair of workpieces, etc. Its advantages are specifically manifested in the following aspects: (1) Refining grains and improving material properties. During the friction stir processing process, under the combined conditions of large strain + high temperature, the stirring zone obtains uniformly refined equiaxed grains through dynamic recrystallization, thereby improving the mechanical properties of the material. (2) Eliminating material structural defects and obtaining a uniform and dense structure. By performing friction stir processing on cast aluminum alloy, the coarse second phase particles and aluminum dendrites of the cast alloy are broken, the casting pores are bridged, the matrix grains are refined, and the mechanical properties of the material, especially the plasticity and fatigue properties, are significantly improved.

[0003] The stirring tool used in traditional friction stir welding / processing technology consists of a shoulder, a stirring needle and a clamping part. When the workpiece surface is subjected to friction stir processing, the stirring tool is inserted at high speed and rotates. As the insertion depth of the stirring needle increases, a large amount of material is squeezed out. Since the shoulder is pressed into the workpiece surface for a certain distance during the friction stir processing, this will cause a certain degree of thinning in the thickness of the workpiece processing area after friction stir welding / processing and flash defects caused by the extrusion of plasticized materials. Therefore, machining methods such as milling are often required after friction stir welding / processing to solve the problems of flatness and surface defects.

[0004] The static shoulder friction stir welding technology is developed on the basis of traditional friction stir welding. The static shoulder welding tool consists of a non-rotating shoulder and an internal rotating stirring tool. Since the shoulder does not rotate, the surface of the welding area / processing area is smooth, without flash, and there is no thinning in the thickness direction. In addition, the static shoulder can also reduce the temperature gradient in the thickness direction of the welding / processing area, optimizing the organization and performance of the welding / processing area.

[0005] The Chinese patent with publication number CN108788445A discloses a friction stir welding device for a stationary shoulder, and the Chinese patent with publication number CN110666337A discloses a pressure-displacement coordinated control friction stir welding device and method for a stationary shoulder. It can be learned from the above two patent applications that, generally speaking, the contact surface between the stationary shoulder and the workpiece is a planar design. When the end face of the aluminum alloy plate or profile is subjected to friction stir processing modification using a planar stationary shoulder profile, a special fixed tool and fixture must be used to form a cavity that controls the flow of plasticized metal using the fixture, the stationary shoulder, and the dynamic shoulder of the stirring tool, thereby obtaining a friction stir processing area without internal defects. For the end face of a workpiece with a complex shape, the design and manufacture of the tool and fixture and the complexity of the friction stir processing process all limit the engineering application of the friction stir processing technology of the stationary shoulder in the modification of the end face of the workpiece. These practical problems also reduce the flexibility of existing friction stir processing equipment.

[0006] Therefore, how to change the current situation in which static shoulder friction stir welding is used in the processing of modified fashion cards has become an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0007] The purpose of the present invention is to provide a groove-type stationary shoulder friction stir processing tool to solve the problems existing in the above-mentioned prior art, simplify the clamping difficulty when the stationary shoulder friction stir welding is applied to processing modification, improve the surface quality of the processing area, and reduce the subsequent processing amount.

[0008] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a groove-type stationary shoulder friction stir processing tool, comprising a stirring head, a fixed sleeve, a groove-type stationary shoulder device, a thrust ball bearing and a cushion block assembly, one end of the stirring head has a stirring needle, the stirring head can be connected to the main shaft of the friction stir processing equipment, the fixed sleeve is connected to the groove-type stationary shoulder device, the thrust ball bearing is connected to the groove-type stationary shoulder device, the fixed sleeve can also be connected to the main shaft box of the friction stir processing equipment, the cushion block assembly is detachably connected to the groove-type stationary shoulder device, the cushion block assembly includes two oppositely arranged side cushion blocks, the spacing between the two side cushion blocks can be adjusted, the fixed sleeve and the groove-type stationary shoulder device are both provided with through holes, the stirring head can rotatably pass through the through hole, and the stirring needle is located between the two side cushion blocks.

[0009] Preferably, the two side gaskets have opposite sides each having an arc surface protruding toward the stirring needle.

[0010] Preferably, the side of the side gasket facing the stirring needle has two arc surfaces and a plane, the plane is located between the two arc surfaces, the arc surface and the plane have a smooth transition, and the distance between the highest point of the arc surface and the stirring needle is greater than the distance between the plane and the stirring needle.

[0011] Preferably, the groove-type stationary shoulder device has two installation positions that are arranged opposite to each other, and there is a gap between the two installation positions that can allow the workpiece to pass through, and the side pad is arranged in the installation position.

[0012] Preferably, the side gasket is connected to the mounting position by means of connecting bolts, the mounting position is provided with a threaded through hole matched with the connecting bolt, and the side of the side gasket away from the stirring needle is provided with a threaded blind hole matched with the connecting bolt.

[0013] Preferably, the installation position is U-shaped, and the openings of the two installation positions are arranged opposite to each other.

[0014] Preferably, a connecting head is provided at one end of the groove-type stationary shoulder device away from the side pad, and the fixing sleeve has a connecting hole matching the connecting head, the connecting head is inserted into the connecting hole, and the fixing sleeve is also provided with an adjusting bolt, and the adjusting bolt can tighten the connecting head.

[0015] Preferably, the connecting head has a limiting groove, the groove-type stationary shoulder device can be rotatably connected to the fixing sleeve by means of the limiting groove, and one end of the adjusting bolt extending into the connecting hole can abut against the limiting groove.

[0016] Preferably, a connecting thread is provided on a side of the stirring head away from the stirring needle, and the stirring head can be threadably connected to a main shaft of the friction stir processing equipment.

[0017] Compared with the prior art, the present invention has achieved the following technical effects: the grooved stationary shoulder friction stirring processing tool of the present invention comprises a stirring head, a fixed sleeve, a grooved stationary shoulder device, a thrust ball bearing and a cushion block assembly, one end of the stirring head is provided with a stirring needle, the stirring head can be connected to the main shaft of the friction stirring processing equipment, the fixed sleeve is connected to the grooved stationary shoulder device, the thrust ball bearing is connected to the grooved stationary shoulder device, the fixed sleeve can also be connected to the main shaft box of the friction stirring processing equipment, the cushion block assembly is detachably connected to the grooved stationary shoulder device, the cushion block assembly comprises two oppositely arranged side cushion blocks, the spacing between the two side cushion blocks can be adjusted, the fixed sleeve and the grooved stationary shoulder device are both provided with through holes, the stirring head can rotatably pass through the through hole, and the stirring needle is located between the two side cushion blocks. When using the grooved stationary shoulder friction stir processing tool of the present invention, the stirring head is connected to the main shaft of the friction stir processing equipment, the fixed sleeve is connected to the main shaft box of the friction stir processing equipment, the grooved stationary shoulder device and the pad assembly cooperate to form an effective clamping effect on the side of the workpiece, and the stirring needle can process the processing area to obtain a uniform and dense tissue structure, eliminate tissue defects, and make the surface of the processing area flat and smooth, reducing the subsequent milling amount. The present invention can realize the friction stir processing of local or small-format workpieces without the need for complex tooling clamping. The spacing between the two side pads can be adjusted, thereby achieving the purpose of adjusting the side pressure of the workpiece, eliminating the tunnel hole defects formed due to insufficient pressure, and the side pads can be replaced after wear, ensuring the reliability of the processing technology and saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 It is a schematic diagram of the disassembled structure of the grooved stationary shoulder friction stir processing tool of the present invention;

[0020] Figure 2 It is a schematic diagram of the grooved stationary shoulder friction stir processing tool of the present invention processing a straight wall workpiece;

[0021] Figure 3 It is a schematic diagram of the grooved stationary shoulder friction stir processing tool of the present invention processing a curved wall workpiece;

[0022] Among them, 1 is a stirring head, 2 is a fixed sleeve, 3 is a thrust ball bearing, 4 is a groove-type stationary shoulder device, 5 is a side pad, 6 is a pad mounting position, 7 is a bearing mounting position, 8 is a limit groove, 9 is a connecting hole, and 10 is a stirring needle. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The purpose of the present invention is to provide a groove-type stationary shoulder friction stir processing tool to solve the problems existing in the above-mentioned prior art, simplify the clamping difficulty when the stationary shoulder friction stir welding is applied to processing modification, improve the surface quality of the processing area, and reduce the subsequent processing amount.

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Please refer to Figure 1-3 ,in, Figure 1 Schematic diagram of the disassembled structure of the grooved stationary shoulder friction stir processing tool of the present invention, Figure 2 It is a schematic diagram of the groove type stationary shoulder friction stir processing tool of the present invention processing a straight wall workpiece, Figure 3 The schematic diagram of the grooved static shoulder friction stir processing tool of the present invention processing a curved wall workpiece is shown. The tool comprises a stirring head 1, a fixed sleeve 2, a thrust ball bearing 3, a grooved static shoulder device 4 and a cushion block assembly. One end of the stirring head 1 has a stirring pin 10. The stirring head 1 can be connected to the main shaft of the friction stir processing device. The fixed sleeve 2 is connected to the grooved static shoulder device 4. The fixed sleeve 2 is connected to the thrust ball bearing 3. The fixed sleeve 2 can also be connected to the main shaft box of the friction stir processing device. The cushion block assembly is detachably connected to the grooved static shoulder device 4. The cushion block assembly comprises two side cushion blocks 5 arranged opposite to each other. The spacing between the two side cushion blocks 5 can be adjusted. The fixed sleeve 2 and the grooved static shoulder device 4 are both provided with through holes. The stirring head 1 can rotatably pass through the through holes. The stirring pin 10 is located between the two side cushion blocks 5.

[0027] When using the grooved stationary shoulder friction stir processing tool of the present invention, the stirring head 1 is connected to the main shaft of the friction stir processing equipment, the fixed sleeve 2 is connected to the main shaft box of the friction stir processing equipment, the grooved stationary shoulder device 4 and the pad assembly cooperate to form an effective clamping effect on the side of the workpiece, and the stirring needle 10 can process the processing area to obtain a uniform and dense tissue structure, eliminate tissue defects, and make the surface of the processing area flat and smooth, reducing the subsequent milling amount. The present invention can realize the friction stir processing of local or small-format workpieces without the need for complex tooling clamping. The spacing between the two side pads 5 can be adjusted, thereby achieving the purpose of adjusting the side pressure of the workpiece, eliminating the tunnel hole defects formed due to insufficient pressure, and the side pads 5 can be replaced after wear, ensuring the reliability of the processing technology and saving production costs.

[0028] It should be emphasized that the opposite sides of the two side pads 5 have an arc surface protruding toward the stirring needle 10. When processing an arc-surface workpiece, the arc surface of the side pad 5 can effectively clamp the arc-surface workpiece. At the same time, the arc surface can prevent the side pad 5 from damaging the processed workpiece, thereby improving the working stability of the processing tool.

[0029] In this specific embodiment, the side of the side gasket 5 facing the stirring needle 10 has two curved surfaces and a flat surface, and the flat surface is located between the two curved surfaces. When processing a planar workpiece, the flat surface of the side gasket 5 clamps the workpiece, and the curved surface and the flat surface transition smoothly to avoid damage to the workpiece. The distance between the highest point of the curved surface and the stirring needle 10 is larger than the distance between the flat surface and the stirring needle 10, to avoid the curved surface affecting the work of the flat surface.

[0030] Specifically, the groove-type stationary shoulder device 4 has two relatively arranged mounting positions 6, and there is a gap between the two mounting positions 6 to allow the workpiece to pass through. The side pad 5 is arranged in the mounting position 6, and the mounting position 6 can position the side pad 5 to avoid misalignment of the side pad 5 during processing. The side pad 5 cooperates with the groove-type stationary shoulder device 4 to clamp the processed workpiece. The side pad 5 and the groove-type stationary shoulder device 4 are detachably connected to facilitate replacement of the side pad 5 and adjustment of the gap between the side pads 5.

[0031] In this specific embodiment, the side gasket 5 is connected to the mounting position 6 by connecting bolts. The mounting position 6 is provided with a threaded through hole compatible with the connecting bolt. The side of the side gasket 5 away from the stirring needle 10 is provided with a threaded blind hole compatible with the connecting bolt. The connecting bolt passes through the threaded through hole and is connected to the side gasket 5. Adjusting the connecting bolt can achieve the purpose of adjusting the gap between the two side gaskets 5.

[0032] More specifically, the mounting position 6 is U-shaped, and the openings of the two mounting positions 6 are arranged opposite to each other. The U-shaped mounting position 6 better positions the side pad 5. When there is a gap between the side pad 5 and the bottom of the mounting position 6, the side wall of the mounting position 6 can still provide a limiting effect for the side pad 5, thereby avoiding misalignment of the side pad 5 and improving the reliability of the processing tool.

[0033] Furthermore, the groove-type static shaft shoulder device 4 is connected to the thrust ball bearing 3, and the groove-type static shaft shoulder device 4 has an installation position with the thrust ball bearing 3. In addition, the limiting groove 8 of the groove-type static shaft shoulder device 4 is used to connect the fixing sleeve 2 and the groove-type static shaft shoulder device 4, so as to prevent the groove-type static shaft shoulder device 4 from falling off, and to realize the rotation of the curved workpiece processing. In addition, an adjusting bolt is also provided between the connecting head and the fixing sleeve 2, and the adjusting bolt can be used to tighten the limiting groove 8 on the connecting head, fix the relative position between the fixing sleeve 2 and the groove-type static shaft shoulder device 4, and prevent the groove-type static shaft shoulder device 4 from rotating when the processing tool is processing a straight wall, thereby improving the stability of the processing tool.

[0034] Furthermore, a connecting thread is provided on the side of the stirring head 1 away from the stirring needle 10, and the stirring head 1 can be connected with the main shaft thread of the stir friction processing equipment, which is convenient for disassembly and assembly, and reduces the workload of the operator.

[0035] The groove-type stationary shoulder friction stir processing tool of the present invention can realize the modification work of the friction stir processing of local or small-area workpieces, refine the organization of the processing area, eliminate internal defects, obtain a uniform and dense organizational structure, and improve its comprehensive mechanical properties. The processing tool of the present invention has the advantages of simple structure and strong adaptability, reduces the requirements of the friction stir processing on the fixture, and the surface of the processing area is smooth and flat, reducing the subsequent surface processing amount. In addition, the spacing of the side pads 5 can be adjusted, which increases the flexibility of the friction stir processing of workpieces of different sizes.

[0036] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A grooved stationary shoulder friction stir processing tool, characterized in that: It includes a stirring head, a fixed sleeve, a groove-type stationary shoulder device, a thrust ball bearing and a cushion block assembly, one end of the stirring head is provided with a stirring needle, the stirring head can be connected to the main shaft of the stir friction processing equipment, the fixed sleeve is connected to the groove-type stationary shoulder device, the thrust ball bearing is connected to the groove-type stationary shoulder device, the fixed sleeve can also be connected to the main shaft box of the stir friction processing equipment, the cushion block assembly is detachably connected to the groove-type stationary shoulder device, the cushion block assembly includes two oppositely arranged side cushion blocks, the spacing between the two side cushion blocks can be adjusted, the fixed sleeve and the groove-type stationary shoulder device are both provided with through holes, the stirring head can rotatably pass through the through holes, the stirring needle is located between the two side cushion blocks; the groove-type stationary shoulder device has two oppositely arranged mounting positions, there is a gap between the two mounting positions that can allow the workpiece to pass through, and the side cushion block is arranged in the mounting position; A connecting head is arranged at one end of the groove-type stationary shoulder device away from the side pad, and the fixing sleeve has a connecting hole matching the connecting head, the connecting head is inserted into the connecting hole, and the fixing sleeve is also provided with an adjusting bolt, and the adjusting bolt can tighten the connecting head.

2. The grooved stationary shoulder friction stir processing tool according to claim 1, characterized in that: The opposite sides of the two side gaskets both have an arc surface protruding toward the stirring needle.

3. The grooved stationary shoulder friction stir processing tool according to claim 2, characterized in that: The side of the side pad facing the stirring needle has two arc surfaces and a plane, the plane is located between the two arc surfaces, the arc surface and the plane have a smooth transition, and the distance between the highest point of the arc surface and the stirring needle is greater than the distance between the plane and the stirring needle.

4. The grooved stationary shoulder friction stir processing tool according to claim 1, characterized in that: The side gasket is connected to the mounting position by connecting bolts. The mounting position is provided with a threaded through hole matched with the connecting bolt. The side of the side gasket away from the stirring needle is provided with a threaded blind hole matched with the connecting bolt.

5. The grooved stationary shoulder friction stir processing tool according to claim 4, characterized in that: The installation position is U-shaped, and the openings of the two installation positions are arranged opposite to each other.

6. The grooved stationary shoulder friction stir processing tool according to claim 1, characterized in that: The connecting head has a limiting groove, and the groove-type stationary shoulder device can be rotatably connected with the fixing sleeve by means of the limiting groove, and one end of the adjusting bolt extending into the connecting hole can abut against the limiting groove.

7. The grooved stationary shoulder friction stir processing tool according to any one of claims 1 to 6, characterized in that: A connecting thread is arranged on a side of the stirring head away from the stirring needle, and the stirring head can be threadedly connected to a main shaft of a friction stir processing device.

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