Stir friction wire feeding additive manufacturing device and stir friction wire feeding additive manufacturing method

Abstract

The present invention relates to the technical field of stir friction additive manufacturing, and in particular to a stir friction wire feeding additive manufacturing device and a stir friction wire feeding additive manufacturing method, comprising a stirring shaft and a shoulder, the stirring shaft can rotate around its own axis, and a spiral groove is provided on the stirring shaft; the shoulder is hollowly arranged along its own axial direction, and the shoulder is coaxially sleeved on the stirring shaft, and the inner wall of the shoulder and the spiral groove are enclosed to form a feeding channel; a wire feeding hole is provided on the shoulder, and the wire feeding hole is connected to the inner wall of the shoulder, so as to feed the wire into the feeding channel through the wire feeding hole; a pressure hole is also provided on the shoulder, and the pressure hole is connected to the inner wall of the shoulder, so as to convey positive pressure gas to the feeding channel through the pressure hole; the wire fed into the feeding channel is cut by the spiral groove and forms material particles, and the material particles move along the feeding channel, and the positive pressure gas provides extrusion auxiliary driving force for the material particles. The present invention can effectively avoid problems such as material jamming and insufficient extrusion, and improve the production quality and production efficiency of stir friction additive manufacturing.

Description

Technical Field

[0001] The present invention relates to the technical field of friction stir additive manufacturing, and in particular to a friction stir wire feeding additive manufacturing device and a friction stir wire feeding additive manufacturing method. Background Art

[0002] Additive manufacturing technology manufactures solid parts by gradually adding materials. Traditional additive manufacturing technology usually uses laser beams, arcs, etc. as heat sources for additive manufacturing, which is suitable for the manufacture of high-temperature alloys. However, due to problems such as low precision of formed parts and poor surface quality, traditional additive manufacturing technology is difficult to manufacture large high-strength aluminum alloy integral structural parts.

[0003] Friction stir additive manufacturing technology is a solid-phase non-melting additive manufacturing method based on friction stir welding technology. It uses the friction heat generated by the stirring head and plastic deformation to fuse the additive material with the substrate, and transforms the three-dimensional complex-shaped structural parts into simple two-dimensional plane shapes by layer-by-layer reciprocating superposition, thereby realizing additive manufacturing. In the process of additive manufacturing using friction stir additive manufacturing technology, defects such as pores and cracks generated by traditional additive manufacturing methods during the melting and solidification process can be avoided, ensuring that the additive area has good mechanical properties. Therefore, friction stir additive manufacturing technology has been widely used in the manufacture of lightweight alloys such as aluminum alloys and magnesium alloys.

[0004] In the past, the additive materials used in friction stir additive manufacturing were mainly plates and rods. Due to the disadvantages of discontinuous feeding and large structural dimensions, the use of wires can effectively solve the above problems. During the production process, the wire is cut and moved along the axial direction of the stirring shaft and merged with the substrate to achieve additive manufacturing. Although the material utilization rate is improved, during the additive manufacturing process, the cut wire is prone to form chips on the surface of the stirring shaft, which in turn leads to problems such as material jamming, insufficient extrusion, and even adhesion between the stirring shaft and the shaft shoulder, reducing production quality and efficiency. Summary of the invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the problems of material jamming, insufficient extrusion volume, low production quality and production efficiency that easily occur during the production process of the existing stir friction additive device, and to provide a stir friction wire feeding additive device and a stir friction wire feeding additive manufacturing method to effectively avoid problems such as material jamming and insufficient extrusion volume, and improve the production quality and production efficiency of stir friction additive manufacturing.

[0006] In the first aspect, the present invention provides a friction stir wire feeding additive device, comprising a stirring shaft, which can rotate around its own axis and is provided with a spiral groove; a shoulder, which is hollow along its own axial direction and coaxially sleeved on the stirring shaft, and the inner wall of the shoulder and the spiral groove are enclosed to form a feeding channel; a wire feeding hole is provided on the shoulder, and the wire feeding hole passes through the inner wall of the shoulder, so as to feed the wire into the feeding channel through the wire feeding hole; an air pressure hole is also provided on the shoulder, and the air pressure hole passes through the inner wall of the shoulder, so as to convey positive pressure gas to the feeding channel through the air pressure hole; wherein the wire fed into the feeding channel is cut by the spiral groove and formed into material particles, the material particles move along the feeding channel, and the positive pressure gas provides extrusion auxiliary driving force for the material particles.

[0007] In one embodiment of the present invention, a pressure regulating component is further included. The pressure regulating component is disposed on the shaft shoulder and is connected to the air pressure hole. The pressure regulating component is used to adjust the pressure of the positive pressure gas.

[0008] In one embodiment of the present invention, a plurality of spiral grooves are provided, and the plurality of spiral grooves are staggered along the axial direction of the stirring shaft; each of the spiral grooves includes a cutting section and a spiral section, the cutting sections of the plurality of spiral grooves are located at the same axial position of the stirring shaft and are evenly distributed along the circumferential direction of the stirring shaft, the cutting section includes a cutting surface, and the cutting surface is used to cut the wire material and form the material particles; one end of the spiral section is connected to the cutting section, and the other end of the spiral section is connected to the axial end face of the stirring shaft; wherein the stirring shaft rotates and drives the cutting section to connect to the wire feeding hole and the air pressure hole in sequence.

[0009] In one embodiment of the present invention, a heating component is further included. The heating component is disposed on the shaft shoulder and is disposed close to the discharge end of the feed channel. The heating component is used to provide heat for plasticizing the material particles in the feed channel.

[0010] In one embodiment of the present invention, a cooling component is further included. The cooling component is arranged on the shaft shoulder. The cooling component is arranged close to the feeding end of the feeding channel. The cooling component is used to prevent heat from being transferred to one side of the wire feeding hole.

[0011] In one embodiment of the present invention, a spiral liquid groove is provided on the outer wall of the shaft shoulder; the cooling component is configured as a cooling ring cover, the cooling ring cover is coaxially sleeved on the shaft shoulder, the inner wall of the cooling ring cover and the spiral liquid groove are enclosed to form a cooling liquid channel, the cooling ring cover is provided with a liquid inlet hole and a liquid outlet hole, the liquid inlet hole and the liquid outlet hole are both connected to the cooling liquid channel, and the liquid inlet hole is arranged on the side of the cooling ring cover along its own axial direction close to the wire feeding hole.

[0012] In one embodiment of the present invention, the lead angle of the spiral liquid groove is not greater than the lead angle of the spiral groove.

[0013] In one embodiment of the present invention, the wire feeding hole is arranged at an angle, wherein the axis of the wire feeding hole and the axis of the stirring shaft form a feeding angle α, 75°≤α≤85°.

[0014] In one embodiment of the present invention, it also includes an atmosphere hood, which is coaxially sleeved on the shaft shoulder, a gas containing space is formed in the atmosphere hood, and a gas injection hole penetrating to the gas containing space is opened on the atmosphere hood for conveying inert gas to the gas containing space through the gas injection hole.

[0015] In a second aspect, the present invention further provides a friction stir wire feeding additive manufacturing method based on any one of the above-mentioned friction stir wire feeding additive devices, comprising: when performing additive manufacturing, delivering the positive pressure gas of a first pressure P1 to the feed channel through the air pressure hole to provide extrusion auxiliary driving force for the plasticized material particles; wherein 0.5Mpa≤P1≤1.0Mpa; when the additive manufacturing is completed, delivering the positive pressure gas of a second pressure P2 to the feed channel through the air pressure hole to extrude the material particles remaining in the feed channel; wherein 1.8Mpa≤P2≤2.2Mpa. .

[0016] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0017] The friction stir wire feeding additive device of the present invention provides positive pressure gas for the feed channel by opening a pressure hole on the shaft shoulder. When performing friction stir additive manufacturing, the positive pressure gas can provide extrusion auxiliary driving force for plasticized material particles, so that the material particles are driven by the positive pressure gas and move along the feed channel. The stable output of material particles can be achieved, and the problems of material jamming, insufficient extrusion volume, adhesion between the stirring shaft and the shaft shoulder, or insufficient heat are effectively prevented, thereby improving the production quality and production efficiency of friction stir additive manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 This is one of the cross-sectional structural schematic diagrams of the friction stir wire feeding additive device in the preferred embodiment of the present invention;

[0020] Figure 2 This is one of the structural schematic diagrams of the friction stir wire feeding additive device in the preferred embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the stirring shaft from a first perspective in a preferred embodiment of the present invention;

[0022] Figure 4 A schematic diagram of the structure of the stirring shaft from a second viewing angle in a preferred embodiment of the present invention;

[0023] Figure 5 It is a schematic cross-sectional view of the stirring shaft in a preferred embodiment of the present invention;

[0024] Figure 6 This is the second structural schematic diagram of the friction stir wire feeding additive device in the preferred embodiment of the present invention;

[0025] Figure 7 It is a schematic diagram of the local structure of the shaft shoulder in the preferred embodiment of the present invention;

[0026] Figure 8 This is a second schematic cross-sectional view of the friction stir wire feeding additive device in a preferred embodiment of the present invention;

[0027] Fig. 9 It is a schematic cross-sectional structure diagram of a wire feeding hole in a preferred embodiment of the present invention;

[0028] Fig.10 This is the third schematic cross-sectional structure diagram of the friction stir wire feeding additive device in the preferred embodiment of the present invention.

[0029] Explanation of the reference numerals in the specification: 10, stirring shaft; 11, spiral groove; 111, cutting section; 1111, cutting surface; 112, spiral section; 12, stirring needle; 20, shaft shoulder; 21, wire feeding hole; 22, air pressure hole; 23, spiral liquid groove; 30, feeding channel; 40, wire; 50, pressure regulating component; 60, heating component; 70, cooling ring cover; 71, liquid inlet hole; 72, liquid outlet hole; 73, sealing component; 80, cold liquid channel; 90, atmosphere cover; 91, gas containing space; 92, gas injection hole. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0031] Reference Figure 1 and Figure 2 As shown, the present invention discloses a friction stir wire feeding additive device, comprising a stirring shaft 10 and a shaft shoulder 20.

[0032] The stirring shaft 10 can rotate around its own axis; those skilled in the art can set the rotation mode of the stirring shaft 10 according to actual needs, for example, by connecting the axial end of the stirring shaft 10 through a mechanical arm, a motor, etc., and driving the stirring shaft 10 to rotate. A spiral groove 11 is provided on the stirring shaft 10; the wire 40 is cut into material particles through the spiral groove 11. On the one hand, the granular material is easier to plasticize, so that it can be fused with the substrate to realize additive manufacturing, which effectively improves the production quality; on the other hand, when the material particles move along the spiral groove 11, the spiral structure of the spiral groove 11 facilitates the movement of the plasticized material particles. When the stirring shaft 10 rotates, the plasticized material moves along the spiral groove under the friction between the spiral groove 11 and the inner wall of the shoulder 20, is extruded from the bottom of the spiral groove and fused with the substrate, which relatively improves the production efficiency. Those skilled in the art can set the number of spiral grooves 11 according to actual needs, such as one, two, three, etc.

[0033] The shoulder 20 is used to cooperate with the stirring shaft 10 to realize friction stir additive manufacturing; specifically, the shoulder 20 is hollow along its own axial direction, and the shoulder 20 is coaxially sleeved on the stirring shaft 10, and the inner wall of the shoulder 20 and the spiral groove 11 enclose a feed channel 30. When performing friction stir additive manufacturing, the shoulder 20 and the stirring shaft 10 can move synchronously along a preset trajectory to realize additive manufacturing; wherein, the shoulder 20 does not rotate, while the stirring shaft 10 rotates to achieve friction plasticization of the material. Those skilled in the art can set a specific method according to actual needs to achieve the synchronous movement of the two along the preset trajectory, such as setting a robotic arm, a three-axis drive device, etc., which will not be repeated.

[0034] A wire feeding hole 21 is provided on the shoulder 20, and the wire feeding hole 21 passes through the inner wall of the shoulder 20, so as to feed the wire 40 into the feeding channel 30 through the wire feeding hole 21. Those skilled in the art can set the number of specific wire feeding holes 21 according to actual needs, such as one, two, three, etc.; in addition, the aperture size of the wire feeding hole 21 can also be adjusted to adapt to wires 40 of different sizes, which will not be repeated. Those skilled in the art can set the specific method of feeding the wire 40 into the wire feeding hole 21 according to actual needs, such as feeding the wire through a wire feeding device, which will not be repeated.

[0035] The shoulder 20 is also provided with an air pressure hole 22, which penetrates the inner wall of the shoulder 20, and is used to deliver positive pressure gas to the feed channel 30 through the air pressure hole 22. When performing stir friction additive manufacturing, although the wire 40 can be plasticized more easily after being cut into material particles, the length of the feed channel 30 is also strictly limited. When the length of the feed channel 30 is too short, insufficient heat is easy to cause insufficient plasticization of the material particles, affecting the production quality; when the length of the feed channel 30 is too long, the structural size will increase, resulting in increased difficulty in disassembly when the stirring shaft 10 and the shoulder 20 are stuck, requiring additional cleaning, reducing production efficiency, and easily causing problems such as stuck material and uneven extrusion, which also affects production quality. To this end, by opening an air pressure hole 22 on the shoulder 20, positive pressure gas is delivered to the feed channel 30 through the air pressure hole 22, and the positive pressure gas provides a certain extrusion auxiliary driving force for the plasticized material particles, so that the material particles can move along the feed channel 30 driven by the positive pressure gas. It can achieve stable output of material particles, effectively prevent problems such as material jamming, insufficient extrusion, adhesion between the stirring shaft 10 and the shoulder 20, or insufficient heat, and improve the production quality and production efficiency of stir friction additive manufacturing.

[0036] When performing stir friction additive manufacturing, the wire 40 is first fed into the feed channel 30 through the wire feeding hole 21; during the feeding process of the wire 40, the stirring shaft 10 rotates and cuts the fed material through the spiral groove 11 to form material particles. After being cut into material particles, the stirring shaft 10 rotates and connects the feed channel 30 to the air pressure hole 22, and the air pressure hole 22 transmits a first pressure P to the feed channel 30. 1 The positive pressure gas is used to provide extrusion auxiliary driving force for the plasticized material particles, so that the material particles are driven by the positive pressure gas and move along the feed channel 30. The material particles driven by the positive pressure gas are plasticized by friction heat generated by the interaction between the spiral groove 11 and the inner wall of the shoulder 20, and then are extruded out of the feed channel 30 and fused with the substrate to realize additive manufacturing.

[0037] Among them, 0.5Mpa≤P 1 ≤1.0Mpa, when the first pressure P 1 When the first pressure P is too small, less than 0.5 MPa, the pressure is too small and may not provide effective force, resulting in failure to drive the material particles to move along the feed channel 30. 2 When the first pressure P is too large, greater than 1.0 MPa, the relative force is too large, which may cause the material particles to be squeezed out of the feed channel 30 too fast, affecting the production quality, resulting in resource waste and increased production costs. 1When the value of is set between 0.5Mpa and 1.0Mpa, it can ensure that the material particles can move at an appropriate speed, plasticize and be extruded out of the feed channel 30, effectively taking into account high production quality and high production efficiency, and preventing problems such as material jamming, insufficient extrusion, bonding, and insufficient plasticization. Those skilled in the art can adjust the specific first pressure P according to actual needs. 1 Set to 0.5Mpa, 0.6Mpa, 0.7Mpa, 0.8Mpa, 0.9Mpa, and 1.0Mpa.

[0038] After the additive manufacturing is completed, the second pressure P is delivered to the feed channel 30 through the air pressure hole 22. 2 The positive pressure gas is used to squeeze out the material particles remaining in the feed channel 30, further avoiding the possibility of particles remaining in the feed channel 30, preventing the stirring shaft 10 and the shaft shoulder 20 from sticking, and avoiding blockage and other problems in the subsequent production process.

[0039] Among them, 1.8Mpa≤P 2 ≤2.2Mpa, when the second pressure P 2 When the pressure is too small, less than 1.8 Mpa, the pressure is too small. When facing the plasticized material particles in the feeding channel 30, the friction between the plasticized material particles and the feeding channel 30 is large, and it may not provide effective force, resulting in the inability to blow out the residual material. 2 When the pressure is too large, greater than 2.2Mpa, the relative force is too large, resulting in waste of resources and increased production costs; it is also easy to cause unnecessary damage to the splashed materials, causing safety hazards. 2 When the value of is set between 1.8Mpa and 2.2Mpa, it can ensure that the material particles are blown out while avoiding resource waste and splashing to cause safety hazards. 2 The value of is set to 2.0Mpa. Of course, those skilled in the art can also change the specific first pressure P according to actual needs. 1 Set to 1.8Mpa, 1.9Mpa, 1.95Mpa, 2.05Mpa, 2.1Mpa, and 2.2Mpa.

[0040] The friction stir wire feeding additive device of the present invention provides positive pressure gas to the feed channel 30 by providing the air pressure hole 22 on the shaft shoulder 20. When performing friction stir additive manufacturing, the positive pressure gas can provide extrusion auxiliary driving force for plasticized material particles, so that the material particles are driven by the positive pressure gas and move along the feed channel 30. The stable output of material particles can be achieved, and the problems of material jamming, insufficient extrusion amount, adhesion between the stirring shaft 10 and the shaft shoulder 20, or insufficient heat are effectively prevented, thereby improving the production quality and production efficiency of friction stir additive manufacturing.

[0041] Preferably, refer to Figure 3 and Figure 4 As shown, a plurality of stirring pins 12 are provided on the axial end face of the stirring shaft 10. It should be noted that the axial end face of the stirring shaft 10 in this application refers to the axial end face of the stirring shaft 10 close to the substrate during the additive manufacturing process. By providing the stirring pins 12 on the axial end face of the stirring shaft 10, the interlayer bonding force is enhanced during the process of friction stirring additive manufacturing, thereby improving the production quality and production efficiency. Preferably, refer to Figure 2 As shown, the shoulder 20 includes a first shoulder 20 split and a second shoulder 20 split coaxially arranged, the first shoulder 20 split is a conical structure, and the second shoulder 20 split is a cylindrical structure. Through the arrangement of this structure, the structural strength of the shoulder 20 itself and the connection effect between the shoulder 20 and the external equipment can be effectively guaranteed, and at the same time, the weight of the shoulder 20 can be reduced to a certain extent, saving energy consumption in the manufacturing process. Preferably, under the premise of providing the first shoulder 20 split and the second shoulder 20 split, the wire feeding hole 21 and the air pressure hole 22 are both arranged on the second shoulder 20 split.

[0042] Reference Figure 2 As shown, the friction stir wire feeding additive device described in the present invention, in some embodiments, further includes a pressure regulating component 50. The pressure regulating component 50 is arranged on the shoulder 20 and is connected to the air pressure hole 22. The pressure regulating component 50 is used to adjust the pressure of the positive pressure gas. Preferably, the pressure regulating component 50 is set as a pressure regulating valve. By setting the pressure regulating component 50, it is convenient to adjust the pressure of the positive pressure gas during the additive manufacturing process; for example, in the process of additive manufacturing, the pressure of the positive pressure gas is adjusted by the pressure regulating component 50, and the pressure is controlled at 0.5Mpa to 1.0Mpa, so that the plasticized material particles can be smoothly extruded, and additive manufacturing is realized, ensuring the production quality and production efficiency. After the additive manufacturing is completed, the pressure of the positive pressure gas is adjusted by the pressure regulating component 50, and the pressure is controlled at 1.8Mpa to 2.2Mpa, so that the possible existing plasticized and unextruded material particles are blown out of the feed channel 30 to prevent them from solidifying in the feed channel 30 and sticking to the shoulder 20.

[0043] Reference Figure 3 , Figure 4 and Figure 5As shown, in some embodiments of the stir friction wire feeding additive device described in the present invention, a plurality of spiral grooves 11 are provided, and the setting of a plurality of spiral grooves 11 can facilitate more efficient feeding and improve production efficiency. Those skilled in the art can set the number of specific spiral grooves 11 according to specific needs, such as two, three, four, etc. The plurality of spiral grooves 11 are staggered along the axial direction of the stirring shaft 10. It can be imagined that the feeding channel 30 formed by each spiral groove 11 and the inner wall of the shoulder 20 is independent and not connected except for the discharge end of the feeding channel 30. The setting of this structure can facilitate the rotation of the stirring shaft 10; after the wire 40 is cut through the spiral groove 11, the stirring shaft 10 rotates and drives the spiral groove 11 to communicate with the air pressure hole 22 located at another position, and the air pressure hole 22 inputs positive pressure gas to drive the extrusion of plasticized material particles; at the same time, the remaining spiral grooves 11 can also perform corresponding actions such as cutting the wire 40 or stirring friction.

[0044] Specifically, each spiral groove 11 includes a cutting section 111 and a spiral section 112. The cutting sections 111 of the plurality of spiral grooves 11 are all located at the same axial position of the stirring shaft 10 and are evenly distributed along the circumferential direction of the stirring shaft 10. Through the arrangement of this structure, it is no longer necessary to additionally arrange corresponding axial driving components to drive the stirring shaft 10 during the friction stir additive manufacturing process, and the cutting can be achieved only by the rotation of the stirring shaft 10 during the friction stir additive manufacturing process; the evenly distributed cutting sections 111 can facilitate uniform cutting and plasticization, thereby achieving additive manufacturing and improving production quality. In addition, when the cutting section 111 is not provided, the feeding time is too short, resulting in too small material particles during wire cutting, which is not conducive to the movement of the material particles. Therefore, the setting of the cutting section can reserve a certain space for the wire feeding of the wire 40, extend the feeding time, ensure that the material particles are of appropriate size, and thus improve production efficiency. Each cutting section 111 includes a cutting surface 1111, which is used to cut the wire 40 and form material particles. When the wire 40 passes through the wire feeding hole 21 and enters the feed channel 30, the rotating stirring shaft 10 drives the cutting surface 1111 to be relatively close to the wire 40, and the cutting surface 1111 provides a shearing force for the wire 40, thereby cutting the wire 40 to form material particles. One end of the spiral section 112 is connected to the cutting section 111, and the other end of the spiral section 112 is connected to the axial end face of the stirring shaft 10. After being cut, the material particles enter the spiral section 112 and are plasticized under the action of stirring friction; finally, under the auxiliary driving force of the positive pressure gas, the plasticized material particles are squeezed out of the feed channel 30 from the end of the spiral section 112 away from the cutting section 111, thereby fusing with the substrate to achieve additive manufacturing.

[0045] Reference Figure 5As shown, taking the stirring shaft 10 with two spiral grooves 11 as an example, when the stirring shaft 10 rotates, it can drive the cutting section 111 to connect to the wire feeding hole 21 and the air pressure hole 22 in sequence. When one of the cutting sections 111 is connected to the wire feeding hole 21, the wire 40 is fed in, and at the same time, under the action of the cutting surface 1111, the wire 40 is cut into material particles, enters the spiral section 112, and is plasticized under the action of stirring friction. As the stirring shaft 10 rotates, the cutting section 111 is connected to the air pressure hole 22. At this time, the air pressure hole 22 delivers positive pressure gas into the feed channel 30 to provide force for the plasticized material particles to prevent problems such as uneven extrusion. At the same time, the cutting section 111 of the other spiral groove 11 is connected to the wire feeding hole 21 to achieve cutting. This is repeated to achieve efficient and rapid stirring friction manufacturing. It should be noted that Figure 5 The arrows in the figure are only schematic symbols added for understanding the scheme.

[0046] Reference Figure 6 and Figure 8 As shown, the friction stir wire feeding additive device described in the present invention, in some embodiments, further includes a heating component 60. When performing friction stir additive manufacturing, the formation of plastic deformation of the material particles does not only rely on the heat generated by the plastic deformation of the material itself, especially in the initial stage, when the material particles are located on the side of the axial end face of the feed channel 30 away from the stirring shaft 10, there is a problem of insufficient heat, resulting in slow progress of thermal plasticization of the material particles and poor plastic fluidity. To this end, by setting a heating component 60, the heating component 60 is arranged on the shoulder 20, and the heating component 60 is used to provide heat for the plasticization of the material particles in the feed channel 30. Those skilled in the art can set different heating components 60 according to actual needs. Preferably, the heating component 60 is set to an inductance coil, and the material of the shoulder 20 is set to metal, and the inductance coil is wound around the outside of the shoulder 20. When performing stir friction additive manufacturing, the inductor coil is powered to generate a magnetic field, and the magnetic flux lines pass through the metal material shoulder 20 and generate heat, thereby heating the material particles in the feed channel 30, providing heat therefor, accelerating the thermal plasticization of the material particles, and improving plastic fluidity. The inductor coil achieves heating based on the Faraday electromagnetic induction principle, with a short preheating time, high thermal efficiency, and uniform heating. It can achieve efficient heating and improve production quality and production efficiency. In addition, since the demand for stir friction heat generation is relatively low, the provision of the heating component 60 can shorten the axial length of the stirring shaft 10 to a certain extent, thereby improving the space utilization of the device and increasing the structural strength.

[0047] Furthermore, the heating component 60 is arranged near the discharge end of the feed channel 30. The discharge end of the feed channel 30 is far away from the cutting section 111. Although the heating component 60 can provide heat for the material particles, if the material particles are plasticized too early, it will also cause the wire feeding hole 21 to be blocked, thereby hindering the smooth cutting of the wire 40 and reducing production efficiency. To this end, by arranging the heating component 60 near the discharge end of the feed channel 30, that is, arranging the heating component 60 relatively close to the axial end face of the stirring shaft 10, it is possible to prevent the plasticized material particles from clogging the wire feeding hole 21, thereby ensuring the normal operation of the device and the continuity of manufacturing, thereby improving production quality and production efficiency.

[0048] Preferably, a temperature detection component, such as an infrared temperature detection component, is also provided, which is not shown in the figure; by providing the temperature detection component, the plasticizing temperature of the material particles located on the side of the axial end face of the feeding channel 30 close to the stirring shaft 10 is ensured to be maintained within a certain range, thereby ensuring production quality.

[0049] Reference Figure 6 As shown, the friction stir wire feeding additive device described in the present invention, in some embodiments, also includes a cooling component. Regardless of whether a heating component 60 is provided, heat will be generated in the case of friction stir. If the heat is transferred axially toward the side of the wire feeding hole 21, the temperature near the wire feeding hole 21 will be too high, resulting in premature plasticization of the material particles, hindering the cutting of the wire 40, and even blocking the wire feeding hole 21. To this end, a cooling component is integrated on the shoulder 20, and the cooling component is arranged near the feed end of the feed channel 30 to prevent heat from being transferred to the side of the wire feeding hole 21 through the cooling component. The feed end of the feed channel 30 is the side where the cutting section 111 is located. By providing a cooling component, heat can be effectively prevented from being transferred to the side of the wire feeding hole 21, thereby preventing premature plasticization of the material particles, and then blocking the wire feeding hole 21, insufficient extrusion, and other problems, effectively improving production efficiency and production quality. In the case of a heating component 60, the cooling component and the heating component 60 can cooperate with each other to achieve zoned temperature control of the stirring shaft 10, further improving production quality and production efficiency. Those skilled in the art can set different cooling components according to actual needs.

[0050] Reference Figure 7 and Figure 8As shown, in the friction stir wire feeding additive device described in the present invention, in some embodiments, a spiral liquid groove 23 is provided on the outer wall of the shaft shoulder 20. The cooling component is set as a cooling ring cover 70, and the cooling ring cover 70 is coaxially sleeved on the shaft shoulder 20. The inner wall of the cooling ring cover 70 and the spiral liquid groove 23 are enclosed to form a cooling liquid channel 80. The cooling liquid channel 80 can be injected with cooling liquid to prevent heat from being transferred to the wire feeding hole 21 and to achieve temperature control. The cooling ring cover 70 is provided with a liquid inlet through hole 71 and a liquid outlet through hole 72, and the liquid inlet through hole 71 and the liquid outlet through hole 72 are both connected to the cooling liquid channel 80, so that the cooling liquid is injected through the liquid inlet through hole 71 and discharged through the liquid outlet through hole 72, so as to form a circulating cooling and further improve the cooling effect. Among them, the liquid inlet through hole 71 is arranged on the side of the cooling ring cover 70 axially close to the wire feeding hole 21. It can be imagined that after a period of heat absorption, the temperature of the coolant rises and the relative cooling effect decreases. To this end, the liquid inlet hole 71 is set on the axial side of the cooling ring cover 70 close to the wire feeding hole 21, so that the coolant just injected into the cooling channel from the liquid inlet hole 71 absorbs the heat near the wire feeding hole 21, preventing the heat transfer from causing premature plasticization of the material particles; at the same time, the coolant after absorbing heat is transferred along the coolant channel 80. Since the cooling effect decreases, it will not affect the plasticization of the material particles close to the substrate side, thereby ensuring the production quality. Preferably, a sealing component 73 is also included to provide sealing for the cooling ring cover 70 and the shaft shoulder 20 to prevent leakage of the coolant. Preferably, the sealing component 73 is set as a sealing ring.

[0051] Reference Figure 4 , Figure 7 and Figure 8 As shown, in the friction stir wire feeding additive device described in the present invention, in some embodiments, the lead angle of the spiral liquid groove 23 is not greater than the lead angle of the spiral groove 11. The lead angle is also called the thread rise angle. In the present application, since the spiral liquid groove 23 and the spiral groove 11 are both spiral structures, the lead angle is used to represent the degree of inclination. By setting the lead angle of the spiral liquid groove 23 to be not greater than the lead angle of the spiral groove 11, the relative flow rate of the coolant can be effectively slowed down, thereby ensuring that the coolant can absorb excess heat more evenly and efficiently, preventing heat from being transferred upward to cause premature plasticization of material particles and blockage, affecting production quality and production efficiency. In addition, to a certain extent, more turns of spiral liquid grooves 23 can be set in the same space to ensure the cooling and heat absorption effect.

[0052] Reference Fig. 9As shown, in the friction stir wire feeding additive device described in the present invention, in some embodiments, the wire feeding hole 21 is tilted. Due to the weight and other factors of the shoulder 20, the wall thickness of the shoulder 20 is relatively thin, which affects the effect of the cutting surface 1111 and the shoulder 20 cooperating to cut the wire 40, and thus easily affects the production efficiency and production quality. To this end, by tilting the wire feeding hole 21, it is possible to extend the length of the wire feeding hole 21 to a certain extent without affecting the weight and other factors of the shoulder 20, provide a certain guide for the wire 40, and ensure the stability of feeding and the cutting efficiency of the wire 40. Furthermore, the axis of the wire feeding hole 21 forms a feeding angle α with the axis of the stirring shaft 10, 75°≤α≤85°. When the value of the feeding angle α is too small, less than 75°, the wire feeding hole 21 is too tilted, causing the wire 40 to easily interfere with the shoulder 20 and other components, affecting the feeding efficiency and the quality of the wire 40. When the value of the feeding angle α is too large, greater than 85°, taking the vertical axis of the stirring shaft 10 as an example, the axis of the wire feeding hole 21 tends to be horizontal, and the length of the wire feeding hole 21 is relatively short, which makes it difficult to provide guidance for the feeding of the wire 40. Setting the value of the feeding angle α between 75° and 85° can well balance the guiding effect, feeding efficiency and quality of the wire 40; in addition, it can also allow the wire feeding mechanism for conveying the wire 40 to have a larger installation space. Those skilled in the art can set the specific value of the feeding angle α according to actual needs, such as 75°, 76°, 77°, 78°, 79°, 80°, 81°, 82°, 83°, 84°, 85°, etc.

[0053] Reference Fig.10 As shown, the stir friction wire feeding additive device described in the present invention, in some embodiments, also includes an atmosphere hood 90. The atmosphere hood 90 is used to provide protection for easily oxidized materials such as titanium alloys and steel when adding materials. Specifically, the atmosphere hood 90 is coaxially sleeved on the shoulder 20 to improve space utilization while providing protection, and to avoid interference between the atmosphere hood 90 and other parts during the additive process. A gas containing space 91 is formed in the atmosphere hood 90, and a gas injection hole 92 that passes through the gas containing space 91 is opened on the atmosphere hood 90 to transport inert gas to the gas containing space 91 through the gas injection hole 92. By setting the atmosphere hood 90 to form a gas containing space 91, the inert gas is controlled within a certain range and its speed of dissipation to the surroundings is slowed down. On the one hand, it can effectively provide additive protection for easily oxidized materials, thereby improving production quality; on the other hand, it can effectively save resources and reduce production costs.

[0054] Preferably, the atmosphere cover 90 is detachably connected to the shoulder 20. By making the two detachably connected, it is convenient to pass inert gas into the atmosphere cover 90 for material addition protection when adding easily oxidized materials such as titanium alloy and steel; and when facing other materials, the atmosphere cover 90 can be removed, which reduces the overall weight of the device during the material addition process, saves energy consumption, and reduces production costs; it is also convenient to repair and replace the atmosphere cover 90 when it is damaged. Those skilled in the art can set the specific detachable mode of the two according to actual needs, such as threaded connection, clamping, etc., which will not be repeated. Preferably, when a cooling component, a heating component 60 or a cooling component and a heating component 60 are provided at the same time, the atmosphere cover 90 is set on the outside of these components; taking the heating component 60 and the cooling component as an example, the atmosphere cover 90 is indirectly connected to the shoulder 20 by connecting the cooling component, and the gas accommodating space 91 covers the cooling component and the heating component 60. In order to avoid interference between the atmosphere cover 90 and related components, corresponding openings can also be opened on the atmosphere cover 90 to form avoidance, such as avoiding water pipes, inductance coils, etc.

[0055] The present invention discloses a friction stir wire feeding additive manufacturing method based on the friction stir wire feeding additive device described in any one of the above embodiments, comprising:

[0056] When additive manufacturing is performed, a first pressure P is delivered to the feed channel 30 through the air pressure hole 22. 1 Positive pressure gas is used to provide auxiliary driving force for extrusion of plasticized material particles; 0.5Mpa≤P 1 ≤1.0Mpa;

[0057] After the additive manufacturing is completed, the second pressure P is delivered to the feed material through the air pressure hole 22. 2 Positive pressure gas is used to squeeze out the material particles remaining in the feed channel 30; wherein 1.8Mpa≤P 2 ≤2.2Mpa.

[0058] Working principle:

[0059] When performing additive manufacturing of materials that are easily oxidized, inert gas is introduced into the gas containing space 91 through the gas injection hole 92 to form protection. The wire 40 is fed into the feed channel 30 through the wire feeding hole 21. During the feeding process of the wire 40, the stirring shaft 10 rotates and cuts the wire 40 through the cutting surface 1111 to form material particles. After being cut into material particles, the stirring shaft 10 rotates and connects the feed channel 30 to the air pressure hole 22, and the air pressure hole 22 delivers the first pressure P to the feed channel 30. 1The positive pressure gas is used to provide extrusion auxiliary driving force for the plasticized material particles, so that the material particles are driven by the positive pressure gas and move along the feeding channel 30. The stirring shaft 10 rotates continuously, so that the corresponding cutting section 111 is connected to the wire feeding hole 21 and the air pressure hole 22 in sequence, and the material is fed efficiently.

[0060] In the cooling liquid channel 80, the cooling liquid circulates and cools to prevent the material particles from being plasticized prematurely and causing blockage. The material particles driven by the positive pressure gas generate friction heat to achieve plasticization under the interaction between the spiral groove 11 and the inner wall of the shoulder 20; at the same time, the inductor coil is energized to heat the shoulder 20 to assist in plasticization. Subsequently, the plasticized material particles are squeezed out of the feed channel 30 and merged with the substrate to achieve additive manufacturing.

[0061] After the additive manufacturing is completed, the feed channel 30 is connected to the air pressure hole 22, and the pressure regulating component 50 is adjusted so that the air pressure hole 22 delivers the second pressure P to the feed channel 30. 2 Positive pressure gas is used to squeeze out the material particles remaining in the feed channel 30 to achieve cleaning.

[0062] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A friction stir wire feeding additive device, characterized in that: include: A stirring shaft, the stirring shaft can rotate around its own axis, the stirring shaft is provided with a spiral groove, the spiral groove includes a cutting section and a spiral section, the cutting section includes a cutting surface, one end of the spiral section is connected to the cutting section, and the other end of the spiral section is connected to the axial end surface of the stirring shaft; A shaft shoulder, wherein the shaft shoulder is hollow along its own axial direction and the shaft shoulder is coaxially sleeved on the stirring shaft, and the inner wall of the shaft shoulder and the spiral groove enclose a feeding channel; a wire feeding hole is provided on the shaft shoulder, and the wire feeding hole penetrates to the inner wall of the shaft shoulder, so as to feed the wire into the feeding channel through the wire feeding hole, and the cutting surface is used to cut the wire and form material particles; an air pressure hole is also provided on the shaft shoulder, and the air pressure hole penetrates to the inner wall of the shaft shoulder, so as to transport positive pressure gas to the feeding channel through the air pressure hole; A heating component, wherein the heating component is disposed on the shaft shoulder, the heating component is disposed near the discharge end of the feed channel, and the heating component is used to provide heat for plasticizing the material particles in the feed channel; and A cooling component, wherein the cooling component is arranged on the shaft shoulder, the cooling component is arranged close to the feeding end of the feeding channel, and the cooling component is used to prevent heat from being transferred to one side of the wire feeding hole; Among them, the stirring shaft rotates and drives the cutting section to connect the wire feeding hole and the air pressure hole in sequence, the wire fed into the feeding channel is cut by the spiral groove and forms the material particles, the material particles move along the feeding channel, and the positive pressure gas provides extrusion auxiliary driving force for the material particles.

2. The friction stir wire feeding additive device according to claim 1, characterized in that: It also includes a pressure regulating component, which is arranged on the shaft shoulder and communicated with the air pressure hole, and is used to adjust the pressure of the positive pressure gas.

3. The friction stir wire feeding additive device according to claim 1, characterized in that: There are multiple spiral grooves, and the multiple spiral grooves are staggered along the axial direction of the stirring shaft. The cutting sections of the multiple spiral grooves are all located at the same axial position of the stirring shaft and are evenly distributed along the circumferential direction of the stirring shaft.

4. The friction stir wire feeding additive device according to claim 1, characterized in that: A spiral liquid groove is provided on the outer wall of the shaft shoulder; the cooling component is configured as a cooling ring cover, which is coaxially sleeved on the shaft shoulder, and the inner wall of the cooling ring cover and the spiral liquid groove are enclosed to form a cooling liquid channel, and a liquid inlet through hole and a liquid outlet through hole are provided on the cooling ring cover, and both the liquid inlet through hole and the liquid outlet through hole are connected to the cooling liquid channel, and the liquid inlet through hole is arranged on the side of the cooling ring cover along its own axial direction close to the wire feeding hole.

5. The friction stir wire feeding additive device according to claim 4, characterized in that: The lead angle of the spiral liquid groove is not greater than the lead angle of the spiral groove.

6. The friction stir wire feeding additive device according to claim 1, characterized in that: The wire feeding hole is arranged obliquely, wherein the axis of the wire feeding hole and the axis of the stirring shaft form a feeding angle α, 75°≤α≤85°.

7. The friction stir wire feeding additive device according to claim 1, characterized in that: It also includes an atmosphere cover, which is coaxially sleeved on the shaft shoulder, a gas containing space is formed in the atmosphere cover, and a gas injection hole penetrating to the gas containing space is opened on the atmosphere cover for conveying inert gas to the gas containing space through the gas injection hole.

8. A friction stir wire feeding additive manufacturing method based on the friction stir wire feeding additive manufacturing device according to any one of claims 1 to 7, characterized in that: include: When additive manufacturing is performed, the positive pressure gas of the first pressure P1 is delivered to the feed channel through the air pressure hole to provide extrusion auxiliary driving force for the plasticized material particles; wherein 0.5Mpa≤P1≤1.0Mpa; After the additive manufacturing is completed, the positive pressure gas of the second pressure P2 is delivered to the feed channel through the air pressure hole to squeeze out the material particles remaining in the feed channel; wherein 1.8Mpa≤P2≤2.2Mpa.

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