Forming method, forming head and device for friction stir powder solid phase additive

Abstract

The forming head comprises a material bearing assembly, the material bearing assembly comprises a feeding cavity, a friction cavity and a discharging cavity which are arranged in sequence, the feeding cavity can be communicated with an additive material, a material conveying assembly is arranged in the material bearing assembly and comprises a friction section, the friction section is provided with a friction external thread, and the friction external thread is connected with the friction section. A friction space exists between the friction section and the friction cavity, the friction space is gradually narrowed in the direction close to the discharging cavity, and the material conveying assembly is driven by the driving assembly to rotate relative to the material bearing unit, so that the additive materials entering the material bearing assembly from the feeding cavity move towards the discharging cavity along the friction external threads; through relative rotation between the friction external thread and the friction cavity, the material has the trend of moving towards the narrow part of the friction space, the friction cavity and the friction section can fully extrude and rub the additive material, the physical characteristics of the additive material are improved, and the additive manufacturing forming effect is improved.

Description

Technical Field

[0001] The present invention relates to the field of solid-phase additive manufacturing, and in particular to a forming method, a forming head and a device for solid-phase additive manufacturing of friction stir powder. Background Art

[0002] Solid-phase additive manufacturing involves achieving plastic deformation and material connection by stirring and friction in the solid state of the material. This technology is commonly used in additive manufacturing and welding of metals.

[0003] Existing solid-phase additive manufacturing equipment has poor friction effect on additive materials, and the friction effect on the materials is limited, which affects the quality of additive manufacturing. Summary of the invention

[0004] In order to solve the above technical problems, on the one hand, the present invention provides a forming head for stir friction powder solid phase additive, comprising:

[0005] A material receiving assembly, the material receiving assembly comprising a feed chamber, a friction chamber and a discharge chamber arranged in sequence, the feed chamber being able to communicate with the additive material;

[0006] A material conveying component, the material conveying component is arranged in the material receiving component, the material conveying component includes a friction section, the friction section is provided with a friction external thread, there is a friction space between the friction section and the friction cavity, the friction space gradually shrinks along a first direction, the first direction is a direction from the feed cavity to the discharge cavity;

[0007] A driving assembly, used for driving the feeding assembly to rotate relative to the material receiving unit;

[0008] Wherein, under the rotation of the material conveying assembly, the friction external thread applies a conveying force along the first direction to the additive material.

[0009] Preferably, the thread surface of the friction external thread close to the discharge chamber is perpendicular to the first direction, and the thread surface close to the feed chamber gradually approaches the first direction from the thread bottom to the thread top.

[0010] Preferably, the diameter of the inner wall surface of the friction chamber and the diameter of the outer wall surface of the friction section both gradually decrease along the first direction.

[0011] Preferably, the inner wall surface of the friction chamber and the outer wall surface of the friction section are both conical surfaces that gradually shrink along the first direction, and the taper of the conical surface of the friction chamber is greater than the taper of the conical surface of the friction section.

[0012] Preferably, the feeding assembly further comprises a feeding section and a discharging section, the feeding section, the friction section and the discharging section are arranged in sequence along the first direction, the feeding section is provided with a feeding external thread, the discharging section is provided with a discharging external thread, and the feeding external thread, the friction external thread and the discharging external thread have the same rotation direction;

[0013] Under the rotation of the material conveying assembly, the feed external thread, the external thread and the discharge external thread exert a conveying force on the additive material along the first direction.

[0014] Preferably, the diameter of the feed section is larger than the maximum diameter of the friction section, and the diameter of the discharge section is smaller than or equal to the minimum diameter of the friction section;

[0015] The pitch and height of the feed external thread are greater than the pitch and height of the friction external thread and the discharge external thread.

[0016] Preferably, the feeding assembly further comprises a stirring section, and the stirring section comprises a plurality of stirring heads extending downward from the bottom surface of the discharging section.

[0017] Preferably, the feed chamber comprises a storage area, which is in communication with the additive material and can store the additive material.

[0018] On the other hand, the present invention also provides a friction stir powder solid phase additive device, which uses the forming head as described in any of the above items to discharge materials.

[0019] On the other hand, the present invention also provides a method for forming a friction stir powder solid phase additive material, the method is implemented based on the above-mentioned solid phase additive device, and the method comprises:

[0020] Starting the driving component to drive the stirring component to rotate;

[0021] Introducing powdered additive material into a feed cavity of a material receiving component;

[0022] Based on the rotation of the stirring component, the additive material moves from the feed cavity to the discharge cavity in the material receiving component, and the additive material is stirred, rubbed and squeezed between the stirring component and the material receiving component;

[0023] The additive material is discharged from the discharge cavity, allowing the additive material to flow to the target area and deposit, completing additive forming.

[0024] By applying the technical solution provided by the present invention, the material receiving component includes a feed chamber, a friction chamber and a discharge chamber, the feeding component includes a friction section, and the additive material passes through a friction space composed of the friction chamber and the friction section when flowing from the feed chamber to the discharge chamber, and the friction space gradually narrows in the direction from the feed chamber to the discharge chamber, and a friction external thread is arranged on the friction section. When the feeding component rotates in the material receiving component, the friction external thread exerts a conveying force on the additive material in the friction space to discharge the additive material into the discharge chamber, so that the material has a tendency to move toward the narrow part of the friction space, thereby enabling the additive material to fit closely to the wall of the friction space. Therefore, the friction chamber, the friction section and the friction external thread can fully extrude and rub the additive material, generate more heat, improve the physical properties of the additive material, and enhance the effect of additive manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a cross-sectional view of the overall structure of a forming head for friction stir powder solid phase additive manufacturing provided by one embodiment of the present invention;

[0026] Figure 2 It is a structural schematic diagram of a material receiving assembly of a forming head for friction stir powder solid phase additive manufacturing provided by one embodiment of the present invention;

[0027] Figure 3 It is a schematic structural diagram of a feeding assembly of a forming head for friction stir powder solid phase additive manufacturing provided by one embodiment of the present invention;

[0028] Among them: 1. material receiving assembly; 11. feed chamber; 111. storage area; 12. friction chamber; 13. discharge chamber; 2. feeding assembly; 21. feed section; 22. friction section; 23. discharge section; 24. stirring section; 25. connection section; 3. driving assembly; 4. material inlet; 5. friction space. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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.

[0030] Figure 1 is a cross-sectional view of the overall structure of a forming head for friction stir powder solid phase additive manufacturing provided by one embodiment of the present invention;

[0031] Figure 2 It is a structural schematic diagram of a material receiving assembly of a forming head for friction stir powder solid phase additive manufacturing provided by one embodiment of the present invention;

[0032] Figure 3 It is a schematic structural diagram of a forming head feed assembly for friction stir powder solid phase additive manufacturing provided by one embodiment of the present invention.

[0033] like Figures 1 to 3 As shown, the embodiment of the present invention provides a forming head for stir friction powder solid phase additive, including a material receiving component 1, a material feeding component 2 and a driving component 3, the material receiving component 1 includes a feed chamber 11, a friction chamber 12 and a discharge chamber 13, the feed chamber 11, the friction chamber 12 and the discharge chamber 13 are arranged in sequence, the feed chamber 11 can be connected to the additive material, such as Figure 1 The material inlet 4 shown, the feeding component 2 is located in the material receiving component 1, the feeding component 2 includes a friction section 22, a friction space 5 is formed between the friction section 22 and the friction chamber 12, the direction from the feed chamber 11 to the discharge chamber 13 is the first direction, and the space of the friction space 5 gradually shrinks along the first direction.

[0034] The driving assembly 3 can drive the material conveying assembly 2 to rotate in the material receiving assembly 1 , and the additive material entering the material receiving assembly 1 from the feeding cavity 11 is discharged from the discharging cavity 13 along the friction external thread of the friction section 22 .

[0035] The additive material moves along the feed cavity 11 to the discharge cavity 13 in the material receiving component 1. When passing through the friction cavity 12 and the friction space 5, the friction space 5 gradually shrinks with the movement of the additive material. Therefore, the additive material fits more closely with the friction section 22 and the friction cavity 12, and the interaction force gradually increases, so that the friction section 22, the friction external thread and the friction cavity 12 can fully squeeze and rub the additive material. At the same time, the materials will also rub against each other when flowing to a narrow area, so that the additive material obtains better physical properties and can improve the effect of additive manufacturing.

[0036] Among them, the additive material can be selected from metal powders, such as aluminum alloys, nickel alloys, or other suitable materials. Since the powder has a smaller particle size and a more uniform particle size, when the powder material is squeezed in the friction space, the powder can have a sufficient friction effect inside, and the small-particle powder can be more fully plasticized after being frictionally squeezed, thereby improving the additive molding effect. It should be noted that the forming head provided in the embodiment of the present invention can also be used for materials in other forms, such as welding wire, and can also achieve a more sufficient friction and extrusion effect on the welding wire.

[0037] In addition, the wall surfaces of the friction chamber 12 and the friction section 22 may be as follows: Figure 1 The tapered surface shown may also be a surface of any shape, as long as the inner wall of the friction chamber 12 and the outer wall of the friction section 22 can be gradually brought closer together along the first direction, so that the friction space 5 can be gradually contracted along the first direction.

[0038] It should also be noted that the external thread mentioned here can be a standard mechanical thread or any structure with a spiral shape, for example, a spiral groove is provided on the friction section 22, and when the feeding assembly 2 rotates, the spiral groove on the friction section 22 applies a conveying force along the first direction to the additive material; or, a pressure plate arranged along a spiral shape is installed on the friction section 22, and when the feeding assembly 2 rotates, the spirally arranged pressure plate on the friction section 22 applies a conveying force along the first direction to the additive material. In other words, as long as the conveying force is applied to the additive material during rotation by relying on the spiral structure, so that the additive material moves to a narrower area in the friction space 5, it should fall within the protection scope of this application.

[0039] like Figure 1 and Figure 3 As shown, in one of the preferred embodiments, the friction external thread on the friction section 22 has a thread surface on the side of the discharge chamber 13 that is perpendicular to the first direction, and the thread surface on the side of the feed chamber 11 gradually approaches the first direction from the thread bottom to the thread top. In the space between every two adjacent threads and the friction section 22 and the friction chamber 12, the additive material contacts the thread surface on the side of the feed chamber 11 at the bottom and contacts the thread surface on the side of the discharge chamber 13 at the top, so that when the friction external thread rotates, a stronger conveying force along the first direction is applied to the additive material, and the material is less likely to flow back and overflow.

[0040] Specifically, Figure 1 For example, the first direction is the vertical downward direction, and the tooth surface of the lower side of the friction external thread on the corresponding friction section 22 is the horizontal direction, and the tooth surface on the upper side is in an inclined state. The additive material is in the space between every two adjacent thread tooth surfaces and the friction section 22 and the friction cavity 12, and the thread tooth surface above it is in a horizontal state, and the thread tooth surface below it is tilted downward. When the additive material is subjected to the friction extrusion force, it is easier to move downward along the downward tilted thread tooth surface, and it is not easy to overflow upward, which can improve the powder feeding efficiency and further enhance the tendency of the additive material to move in the first direction, so that the material has a stronger tendency to move into the narrower space below the friction space 5, and further enhances the friction extrusion effect of the wall on the additive material and the friction extrusion effect of the additive materials on each other.

[0041] In addition, the thread surface of the friction section 22 on the side close to the feed chamber 11 can be an inclined surface as shown in the drawings of the present application, or can be a curved surface that tends to be close to the first direction as a whole.

[0042] like Figure 1As shown, in one preferred embodiment, the inner wall surface of the friction chamber 12 and the outer wall surface of the friction section 22 are both conical surfaces, and the taper of the conical inner surface of the friction chamber 12 is greater than the taper of the conical outer surface of the friction section 22, that is, in the radial section along the feeding component 2, the inclined inner wall of the friction chamber 12 and the inclined outer wall of the friction section 22 have an angle of opening obliquely upward, which further improves the volume change rate of the additive material when it moves downward in the conical ring-shaped material holding space, thereby improving the friction and extrusion effect on the additive material. Among them, the top angle of the conical surface of the friction section 22 can be 60 to 65 degrees, and the top angle of the conical surface of the friction chamber 12 can be 3 to 5 degrees larger than that of the friction section 22.

[0043] like Figure 1 and Figure 3 As shown, in one of the preferred embodiments, the feed component 2 also includes a feed section 21 and a discharge section 23, and the feed section 21, the friction section 22, and the discharge section 23 are arranged in sequence from top to bottom, and the feed section 21 and the discharge section 23 are respectively provided with a feed external thread and a discharge external thread, and the feed external thread, the friction external thread and the discharge external thread have the same rotation direction. When the feed component 2 rotates in the material receiving component 1, the additive material flows under the threaded conveying action of the feed section 21, the friction section 22 and the discharge section 23.

[0044] Among them, the axial length of the discharge section 23 can be set relatively short. Since the additive material has undergone relatively sufficient friction and extrusion in the friction section 22 and obtained good physical properties, it is necessary to discharge the material as soon as possible for additive processing to avoid the material staying in the material receiving component 1 for a long time and cooling down, resulting in the loss of good physical properties.

[0045] Further, such as Figure 3 As shown, the diameter of the feed section 21 can be set to be larger than the maximum diameter of the friction section 22, and the diameter of the discharge section 23 can be smaller than or equal to the minimum diameter of the friction section 22, so that an annular platform exists between the lower surface of the feed section 21 and the friction section 22. When the additive material enters the material receiving component 1, the presence of the annular platform can block the upward movement of the material, effectively avoiding the situation in which the material accumulates at the bottom and overflows upward from the gap under pressure during the process of conveying and compacting the material, thereby improving the conveying efficiency and the material pre-compacting effect.

[0046] It is also possible to set the pitch and height of the feed external thread of the feed section 21 to be greater than the pitch and height of the friction external thread and the discharge external thread, such as Figure 3As shown, the pressure of the thread of the feed external thread on the additive material can be increased, further improving the effect of the extrusion friction of the additive material in the friction space 5. It can also improve the material conveying efficiency, further block the upward movement of the material, and effectively avoid the overflow of the material.

[0047] Furthermore, the feed section 21, the friction section 22, and the discharge section 23 can be integrally formed or can be a detachably connected structure. In this case, a variety of specifications of the feed section 21, the friction section 22, and the discharge section 23 can be provided. For example, the feed section 21 and the discharge section 23 can have different diameters, shaft lengths, and thread dimensions. The friction section 22 can have different tapers, top and bottom diameters, shaft lengths, and thread dimensions. A variety of feed sections 21, friction sections 22, and discharge sections 23 can be interchanged and matched to meet different additive processing requirements.

[0048] like Figure 3 As shown, in one of the preferred embodiments, the feed assembly 2 also includes a stirring section 24, the stirring section 24 includes a plurality of stirring heads with the bottom surface of the discharge section 23 extending downward, the stirring heads can be cylindrical or teardrop-shaped, and during the additive forming process after the additive material is discharged from the forming head, the stirring section 24 can be inserted into and stir the previous deposited layer, generating additional stirring and friction to the additive material, generating additional friction heat, which is used to promote the plastic deformation process of the material, and at the same time helps to reduce porosity defects and promote metallurgical bonding of adjacent deposited layers.

[0049] like Figure 1 As shown, in one of the preferred embodiments, the feed chamber 11 also includes a storage area 111, and the material inlet 4 is connected above the storage area 111, and the storage area 111 can be used to store additive materials. In actual use, a certain amount of additive materials can be pre-added to the storage area 111 for storage, and additive processing can be performed with the pre-stored additive materials without continuously conveying materials to the forming head.

[0050] In one specific embodiment, the forming head for solid-phase additive provided in the embodiment of the present invention can be used in a solid-phase additive device. The solid-phase additive device may include a solid-phase additive machine tool. The machine tool spindle is connected to the connecting section 25 of the feed component 2. The material receiving component 1 can be placed on the tooling of the workbench of the machine tool. A workpiece to be additively processed is placed on the workbench. The feed component 2 is driven to rotate by the machine tool spindle, so that the additive material in the material receiving component 1 is discharged from the forming head and the material is sufficiently rubbed and squeezed, which can improve the additive processing effect on the workpiece.

[0051] An embodiment of the present invention also provides a forming method for a forming head of a stir friction powder solid-phase additive manufacturing device, which is implemented based on the above-mentioned solid-phase additive manufacturing device, including: starting a driving component to drive the stirring component to rotate; introducing powdered additive material into a feed chamber of a receiving component; based on the rotation of the stirring component, the additive material moves from the feed chamber to the discharge chamber in the receiving component, and the additive material is subjected to stirring, friction and extrusion between the stirring component and the receiving component; the additive material is discharged from the discharge chamber, so that the additive material flows to the target area and is deposited, thereby completing the additive forming.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention and should be included in the scope of the claims of the present invention.

Claims

1. A forming head for friction stir powder solid phase additive, characterized in that: include: A material receiving assembly, the material receiving assembly comprising a feed chamber, a friction chamber and a discharge chamber arranged in sequence, the feed chamber being able to communicate with the additive material; A material conveying component, the material conveying component is arranged in the material receiving component, the material conveying component includes a friction section, the friction section is provided with a friction external thread, there is a friction space between the friction section and the friction cavity, the friction space gradually shrinks along a first direction, the first direction is a direction from the feed cavity to the discharge cavity; A driving assembly, used for driving the feeding assembly to rotate relative to the material receiving unit; Wherein, under the rotation of the material conveying assembly, the friction external thread applies a conveying force along the first direction to the additive material.

2. The forming head according to claim 1, characterized in that: The thread surface of the friction external thread close to the discharge cavity is perpendicular to the first direction, and the thread surface close to the feed cavity gradually close to the first direction from the tooth bottom to the tooth top.

3. The forming head according to claim 1, characterized in that: The diameter of the inner wall surface of the friction chamber and the diameter of the outer wall surface of the friction section both gradually decrease along the first direction.

4. The forming head according to claim 3, characterized in that: The inner wall surface of the friction chamber and the outer wall surface of the friction section are both conical surfaces that gradually shrink along the first direction, and the conical surface taper of the friction chamber is greater than the conical surface taper of the friction section.

5. The forming head according to claim 1, characterized in that: The feeding assembly further comprises a feeding section and a discharging section, wherein the feeding section, the friction section and the discharging section are arranged in sequence along the first direction, the feeding section is provided with a feeding external thread, the discharging section is provided with a discharging external thread, and the feeding external thread, the friction external thread and the discharging external thread have the same rotation direction; Under the rotation of the material conveying assembly, the feed external thread, the external thread and the discharge external thread exert a conveying force on the additive material along the first direction.

6. The forming head according to claim 5, characterized in that The diameter of the feed section is greater than the maximum diameter of the friction section, and the diameter of the discharge section is less than or equal to the minimum diameter of the friction section; The pitch and height of the feed external thread are greater than the pitch and height of the friction external thread and the discharge external thread.

7. The forming head according to claim 5, characterized in that The material conveying component further comprises a stirring section, and the stirring section comprises a plurality of stirring heads extending downward from the bottom surface of the material discharging section.

8. The forming head according to claim 1, characterized in that The feed chamber includes a storage area, which is in communication with the additive material and can store the additive material.

9. A friction stir powder solid phase additive device, characterized in that: The device uses the forming head described in any one of claims 1 to 8 to discharge materials.

10. A method for forming a friction stir powder solid phase additive, characterized in that: The method is implemented based on the solid phase additive device according to claim 9, and the method comprises: Starting the driving component to drive the stirring component to rotate; Introducing powdered additive material into a feed cavity of a material receiving component; Based on the rotation of the stirring component, the additive material moves from the feed cavity to the discharge cavity in the material receiving component, and the additive material is stirred, rubbed and squeezed between the stirring component and the material receiving component; The additive material is discharged from the discharge cavity, allowing the additive material to flow to the target area and deposit, completing additive forming.

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