A laser and friction composite additive and subtractive manufacturing device and method

Abstract

The present invention provides a laser and friction composite additive and subtractive manufacturing device and method. The device includes: a frame body, a first additive and subtractive component, and a second additive and subtractive component. The first additive and subtractive component includes a laser head and a powder feeding nozzle. A vertical guide rail is arranged on the side surface of the laser head. The powder feeding nozzle is arranged at the end of the laser head and is adapted to send metal powder to the laser focus of the additive laser source. The frame body includes a support and a bracket. The bracket is arranged parallel to the laser head, and a first motion unit adapted to cooperate with the guide rail is arranged on the side surface of the bracket to adjust the vertical movement of the laser head relative to the bracket. The second additive and subtractive component includes a driving motor, a milling cutter, a rotary friction head, and a rotary base. The rotary base is rotationally connected to the bracket. The rotary friction head and the milling cutter are arranged parallel to the laser head, and the rotary friction head and the milling cutter are respectively arranged at both ends in the height direction of the rotary base. The device has a compact structure and low manufacturing cost.

Description

Technical Field

[0001] The present invention relates to the technical field of metal part additive and subtractive manufacturing, and more particularly, to a laser and friction composite additive and subtractive processing device and method. Background Art

[0002] In recent years, due to a series of advantages such as rapidity, flexibility, cost savings, etc., additive manufacturing technology has well made up for the deficiencies of traditional subtractive manufacturing methods and is suitable for the rapid manufacturing of complex parts.

[0003] Compared with the selective laser melting metal 3D printing technology, the laser-assisted additive manufacturing technology is particularly suitable for the manufacturing and repair processes of large-sized metal parts. However, due to the rapid non-equilibrium solidification characteristics of the laser molten pool, problems such as large residual stress and deformation of the additive metal, coarse columnar grains, and obvious crack defects are caused, which is extremely disadvantageous for improving the mechanical properties of the additive metal.

[0004] Friction additive technology is developed on the basis of friction stir processing technology and equipment, and can inherit the advantages of friction stir processing technology such as low solid-phase processing residual stress and refined grains. Therefore, combining the laser-assisted additive process with the friction additive process is expected to realize the manufacturing of large-sized and complex-structured metal parts, and the residual stress and deformation of the parts are small, the grains are refined, and crack and porosity defects are suppressed. However, in the prior art, when combining the laser-assisted additive process with the friction additive process, during the friction additive process, the metal will be extruded and solidified from the edge of the friction surface to form metal flash, significantly increasing the surface roughness of the additive metal, which is not conducive to the formation of the molten pool and the stable and continuous powder feeding process during the laser-assisted additive process. Summary of the Invention

[0005] The problem solved by the present invention is at least one aspect in the existing friction additive process that the metal will be extruded and solidified from the edge of the friction surface to form metal flash, significantly increasing the surface roughness of the additive metal, which is not conducive to the formation of the molten pool and the stable and continuous powder feeding process during the laser-assisted additive process.

[0006] To solve the above problems, the present invention provides a laser and friction composite additive and subtractive processing device, including: a frame body, a first additive and subtractive component, and a second additive and subtractive component, wherein,

[0007] The first additive and subtractive component includes a laser head and a powder feeding nozzle. A vertically oriented guide rail is provided on the side surface of the laser head, and the powder feeding nozzle is disposed at the end of the laser head and is adapted to deliver metal powder to the laser focus of the additive laser source;

[0008] The frame body includes a support and a bracket. The bracket is vertically fixed on the support. The bracket is arranged parallel to the laser head. A first motion unit adapted to cooperate with the guide rail is arranged on the side surface of the bracket. The first motion unit is slidably arranged on the guide rail to adjust the vertical movement of the laser head relative to the bracket.

[0009] The second additive and subtractive component includes a driving motor, a milling cutter, a rotary friction head, and a rotary base. The rotary base is rotatably connected to the bracket. The driving motor is used to connect to the rotary friction head and the milling cutter. The rotary friction head and the milling cutter are arranged parallel to the laser head. The rotary friction head and the milling cutter are respectively arranged at both ends in the height direction of the rotary base.

[0010] Preferably, the rotary base includes a base body and transmission gears arranged at both ends of the base body in the height direction. The base body is rotatably connected to the bracket. The transmission gears are used to be drivingly connected to the driving motor. And the two transmission gears are respectively used to connect the rotary friction head or the milling cutter.

[0011] Preferably, the bracket includes two opposite connection ends. And it is suitable for the rotary base to drive the rotary friction head and the milling cutter to rotate between the two connection ends. The rotary base further includes a connecting shaft rod. Bearings for rotatably connecting with the connecting shaft rod are arranged at both ends in the length direction of the base body. A through hole for cooperating with the connecting shaft rod is arranged inside the base body. The connecting shaft rod is suitable for passing through the bearings and the through hole and connecting between the two opposite connection ends of the bracket.

[0012] Preferably, the two opposite connection ends of the bracket include a first connection end and a second connection end. The second additive and subtractive component further includes a limiting unit. The limiting unit includes a limiting rod rotatably connected to the first connection end, a limiting protrusion and a limiting concave hole arranged on the second connection end. The limiting concave hole is arranged between the two limiting protrusions. And after the limiting rod cooperates with the base body, it enters between the two limiting protrusions and is connected to the limiting concave hole.

[0013] Preferably, limiting grooves for cooperating with the limiting rod are respectively arranged at both ends in the width direction of the base body.

[0014] Preferably, the limiting unit further includes a first fixing piece, a second fixing piece, and a connecting rotating shaft respectively connected to the first fixing piece and the second fixing piece. The first fixing piece and the second fixing piece are relatively arranged in the height direction on the first connection end. And the connecting rotating shaft is rotatably connected to the limiting rod.

[0015] Preferably, a connecting bolt extends outward from the end of the limiting rod away from the connecting rotating shaft, and the connecting bolt is in threaded connection with the limiting concave hole.

[0016] Preferably, an adjusting knob connected to the first moving unit is further provided on the side surface of the bracket, and the adjusting knob is adapted to adjust the vertical movement of the laser head relative to the bracket.

[0017] Compared with the prior art, the laser and friction composite additive and subtractive manufacturing device of the present invention combines laser-assisted additive manufacturing, friction additive manufacturing, and mechanical subtractive manufacturing, reduces the residual stress and deformation of the additive metal, refines the grain structure, inhibits crack defects, effectively avoids the adverse effects of metal flash or deformation formed by friction additive manufacturing on the surface roughness, laser additive manufacturing stability and forming, greatly improves the manufacturing efficiency, processing quality and precision, and the device has a compact structure, small volume, saves processing space, and reduces the manufacturing cost of the equipment; in addition, the device adjusts the vertical distance between the frame body and the laser head, thereby adjusting the vertical distance between the laser focus and the rotary friction head or the milling cutter, so as to meet the different requirements of the laser focus position, friction pressing depth, and milling subtractive depth, and is easy to realize on-site processing or repair of large and complex structural parts or molds.

[0018] The present invention also provides a laser and friction composite additive and subtractive manufacturing method, based on the laser and friction composite additive and subtractive manufacturing device described in any one of the above, including the following steps:

[0019] Step S1, set the processing parameters of the part to be processed;

[0020] Step S2, start the laser head to make the laser focus irradiate the additive area of the part to form a molten pool, and start the powder feeding nozzle to uniformly send metal powder into the molten pool in the additive area of the part to be processed to form an additive metal layer;

[0021] Step S3, start the rotary friction head to perform friction treatment on the surface of the additive metal layer on the part to be processed;

[0022] Step S4, monitor the size of the additive metal flash on the part to be processed in real time. When the size of the additive metal flash exceeds the maximum limit of the surface roughness, turn off the rotary friction head, adjust the rotary base, and align the milling cutter and the laser focus with the position where the additive metal flash is located;

[0023] Step S5, start the laser head to heat the additive metal flash and soften the additive metal flash;

[0024] Step S6, start the milling cutter to perform milling subtractive treatment on the deformed areas such as the heated additive metal flash until the surface roughness of the additive metal reaches the requirements again;

[0025] Step S7: Repeat Step S2 to Step S6, or repeat Step S1 to Step S6 until a predetermined workpiece is obtained, and then perform finish machining on the predetermined workpiece to obtain the workpiece.

[0026] Preferably, Step S4 includes:

[0027] When the size of the additive metal flash exceeds the maximum limit of the surface roughness, turn off the rotary friction head, rotate the connection bolt on the limit rod in the second additive and subtractive component, and the limit rod disengages from the limit concave hole in the second additive and subtractive component to release the limit rod; turn the limit rod to the side away from the rotary base, adjust the rotary base, align the milling cutter and the laser focus with the position where the additive metal flash is located, then turn the limit rod into the limit groove of the rotary base and tighten the connection bolt so that the connection bolt enters the limit concave hole to lock the limit rod.

[0028] Compared with the prior art, in the laser and friction composite additive and subtractive machining method of the present invention, laser-assisted additive, friction additive, and mechanical subtractive are combined to reduce the residual stress and deformation of the additive metal, refine the grain structure, inhibit crack defects, effectively avoid the adverse effects of the metal flash or deformation formed by friction additive on the surface roughness, laser additive stability, and forming, and greatly improve the manufacturing efficiency, processing quality, and precision. Description of the Drawings

[0029] Figure 1 It is the front view schematic diagram of the laser and friction composite additive and subtractive machining device in the embodiment of the present invention;

[0030] Figure 2 It is the bottom view schematic diagram of the laser and friction composite additive and subtractive machining device in the embodiment of the present invention;

[0031] Figure 3 It is the partial structural schematic diagram of the laser and friction composite additive and subtractive machining device in the embodiment of the present invention when releasing the limit rod and preparing to switch to the milling cutter for subtractive machining;

[0032] Figure 4 It is the schematic diagram of the laser and friction composite additive and subtractive machining device in the embodiment of the present invention when switching to the milling cutter for subtractive machining and locking the limit rod;

[0033] Figure 5 It is the structural schematic diagram of the rotary base in the embodiment of the present invention;

[0034] Figure 6 It is the process flow chart of the laser and friction composite additive and subtractive machining method in the embodiment of the present invention;

[0035] Figure 7This is a partial schematic diagram of the laser and friction assisted additive process in the embodiments of the present invention;

[0036] Figure 8 This is a partial schematic diagram of mechanical subtractive removal of metal flash in the embodiments of the present invention.

[0037] Explanation of reference numerals:

[0038] 1 - frame; 2 - first additive and subtractive component; 3 - second additive and subtractive component; 4 - manipulator;

[0039] 11 - support; 12 - bracket; 21 - laser head; 22 - powder feeding nozzle; 31 - drive motor; 32 - rotary friction head; 33 - milling cutter; 34 - rotary base;

[0040] 121 - adjustment knob; 122 - limit rod; 123 - connecting bolt; 124 - limit protrusion; 125 - limit concave hole; 126 - connecting rotating shaft; 311 - stepper motor; 312 - transmission box; 321 - friction working end; 322 - heat dissipation convex part; 323 - heat dissipation concave part; 341 - limit groove; 342 - bearing; 343 - transmission gear; 344 - mounting surface. Detailed implementation manners

[0041] Currently, in the design of laser additive and subtractive hybrid manufacturing platforms, mainly two or more industrial robots are respectively coordinated with a laser additive manufacturing device and a mechanical subtractive manufacturing device to complete the laser additive and mechanical subtractive processes. This can give full play to the flexible processing characteristics of the robots. Due to their advantages in degrees of freedom and accessibility, they are more suitable for manufacturing large and complex structural metal parts. However, using multiple robots will significantly increase the manufacturing cost of the equipment, and the coordinated cooperation of multiple robots also makes path planning and coordinate system setting more complex; although it is also possible to use a single robot in cooperation with a gantry machine tool to avoid the problem of coordinated cooperation of multiple robots, the huge gantry machine tool will significantly increase the floor area of the equipment and cannot achieve on-site operation. In addition, in the design of some existing laser additive and subtractive hybrid manufacturing platforms, an additional laser module is required to preheat the surface of the part, but the additional laser preheating module will increase the manufacturing cost of the equipment, and the relative positions of the laser modules and the subtractive cutting module cannot be adjusted.

[0042] The technical solutions in the embodiments of the present application will be clearly and elaborately described below with reference to the accompanying drawings. In the description of the present invention, it should be understood that the positive direction of "X" in the drawings represents the right side, the reverse direction of "X" represents the left side, the positive direction of "Y" represents the rear side, the reverse direction of "Y" represents the front side, the positive direction of "Z" represents the upper side, and the reverse direction of "Z" represents the lower side. Moreover, the orientation or positional relationship indicated by the terms "X", "Y", and "Z" is based on the orientation or positional relationship shown in the drawings of the specification. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0043] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0044] In the description of the embodiments of the present application, the description of "in some preferred embodiments" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one preferred embodiment or preferred example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0045] Combined Figure 1-4 As shown, the embodiment of the present invention provides a laser and friction composite additive and subtractive manufacturing device, including: a frame body 1, a first additive and subtractive component 2, and a second additive and subtractive component 3, wherein,

[0046] The first additive and subtractive component 2 includes a laser head 21 and a powder feeding nozzle 22. A vertical guide rail is provided on the side of the laser head 21. The powder feeding nozzle 22 is arranged at the end of the laser head 21 and is adapted to send metal powder to the laser focus of the additive laser source.

[0047] The frame body 1 includes a support 11 and a bracket 12. The bracket 12 is vertically fixed on the support 11. The bracket 12 is arranged parallel to the laser head 21. Moreover, a first motion unit adapted to cooperate with the guide rail is provided on the side of the bracket 12. The first motion unit is slidably arranged on the guide rail to adjust the vertical movement of the laser head 21 relative to the bracket 12, wherein the vertical direction is the direction of "Z" in the figure.

[0048] The second additive and subtractive component 3 includes a driving motor 31, a milling cutter 33, a rotary friction head 32, and a rotary base 34. The rotary base 34 is rotatably connected to the bracket 12. The driving motor 31 is used to connect to the rotary friction head 32 and the milling cutter 33. The rotary friction head 32 and the milling cutter 33 are arranged in parallel with the laser head 21, and the rotary friction head 32 and the milling cutter 33 are respectively arranged at both ends of the rotary base 34 in the height direction. It should be noted that in this embodiment, the height direction of the rotary base 34 is the direction of Z in the figure.

[0049] In the laser and friction composite additive and subtractive manufacturing device of this embodiment, laser-assisted additive manufacturing, friction additive manufacturing, and mechanical subtractive manufacturing are combined to reduce the residual stress and deformation of the additive metal, refine the grain structure, inhibit crack defects, effectively avoid the adverse effects of metal burrs or deformation formed by friction additive manufacturing on the surface roughness, laser additive manufacturing stability, and forming, greatly improve the manufacturing efficiency, processing quality, and accuracy, and the device has a compact structure, small volume, saves processing space, and reduces the manufacturing cost of the equipment; in addition, the device adjusts the vertical distance between the frame body 1 and the laser head 21, thereby adjusting the vertical distance between the laser focus and the rotary friction head 32 or the milling cutter 33, so as to meet the different requirements of the laser focus position, friction pressing depth, and milling subtractive depth, and is easy to realize on-site processing or repair of large and complex structural parts or molds.

[0050] It should be noted that in this embodiment, the specific types of the guide rail and the first motion unit are not further limited, and those skilled in the art can select according to the actual situation as long as the first motion unit can be slidably connected to the guide rail. For example: the guide rail is a slide rail, and the first motion unit can be a slider, or the guide rail can be a toothed guide rail, and the first motion unit can be a gear.

[0051] In this embodiment, a connection seat suitable for connecting with the manipulator 4 is further provided on the side of the bracket 12 away from the support 11. Thus, taking advantage of the quick response and high flexibility of the manipulator 4, laser additive manufacturing, friction additive manufacturing, and mechanical subtractive manufacturing of the workpiece to be processed are carried out quickly, and the device only needs to cooperate with a single manipulator 4 to process the workpiece to be processed, further reducing the manufacturing cost of the equipment and avoiding the problem of difficult coordination of multiple industrial robots.

[0052] In this embodiment, in order to facilitate the adjustment of the vertical movement of the laser head 21 relative to the bracket 12, an adjustment knob 121 connected to the first motion unit is further provided on the side of the bracket 12. The adjustment knob 121 is suitable for adjusting the vertical movement of the laser head 21 relative to the bracket 12, so as to adjust the milling depth, the distance between the laser focus O and the surface of the workpiece to be processed, and the distance between the rotary friction head 32 and the surface of the part.

[0053] Combined Figure 5As shown, in some preferred embodiments, the rotating base 34 includes a base body and transmission gears 343 arranged at both ends of the base body in the height direction. The base body is rotatably connected to the bracket 12. The transmission gears 343 are used for driving connection with the driving motor 31, and the two transmission gears 343 are respectively used for connecting the rotary friction head 32 or the milling cutter 33.

[0054] It should be noted that in this embodiment, no further limitation is imposed on the driving motor 31. Those skilled in the art can make a selection according to the actual situation as long as the driving motor 31 can drive the rotary friction head 32 or the milling cutter 33. In some preferred embodiments, the driving motor 31 includes a stepping motor 311 and a transmission box 312. Among them, the stepping motor 311 is parallel to the bracket 12 and vertically arranged on the support 11 to further reduce the volume of the laser and friction composite additive and subtractive processing device and save the processing space. The gears of the transmission box 312 are meshed with the transmission gears 343 of the rotating base 34. The stepping motor 311 drives the gears in the transmission box 312 to rotate, thereby driving the rotary friction head 32 or the milling cutter 33 to rotate.

[0055] In some preferred embodiments, an installation surface 344 is provided on the transmission gear 343. The installation surface 344 is used for detachable connection with the driving rotary friction head 32 or the milling cutter 33, so as to facilitate the replacement of the rotary friction head 32 or the milling cutter 33 when the rotary friction head 32 or the milling cutter 33 is damaged.

[0056] In this embodiment, the lengths of the rotary friction head 32 and the milling cutter 33 are equal. Thus, without adjusting the manipulator 4 and the adjustment knob 121, it can be ensured that the vertical distance between the center of the working end face of the switched milling cutter 33 and the laser focus is consistent with the center of the working end face of the rotary friction head 32. Only the laser focus and the center of the working end face of the milling cutter 33 need to be adjusted to align with the flash in the horizontal plane, and there is no need to adjust the distance between the laser focus and the working end face of the milling cutter 33 in the vertical direction, improving the processing accuracy and efficiency. It should be noted that in this embodiment, the length directions of the rotary friction head 32 and the milling cutter 33 are the direction of Z in the figure.

[0057] In this embodiment, the bracket 12 includes two relatively arranged connection ends, and between the two connection ends, it is suitable for the rotating base 34 to drive the rotary friction head 32 and the milling cutter 33 to rotate; the rotating base 34 further includes a connecting shaft rod. Bearings 342 for rotational connection with the connecting shaft rod are arranged at both ends of the base body in the length direction. A through hole matching with the connecting shaft rod is arranged inside the base body. The connecting shaft rod is suitable for passing through the bearings 342 and the through hole and connecting between the two relatively arranged connection ends of the bracket 12. It should be noted that the length direction of the base body is the direction of X in the figure, and the two connection ends are relatively arranged along the direction of X in the figure.

[0058] In this embodiment, there is no limitation on the shapes of the connecting shaft rod and the through hole. In some preferred embodiments, the cross-sectional shapes of the connecting shaft rod and the through hole are circular, and the structure is simple.

[0059] Combined with Figure 3 As shown, in some preferred embodiments, the two relatively arranged connecting ends of the bracket 12 include a first connecting end and a second connecting end, and the first connecting end is closer to the laser head 21 than the second connecting end. The second additive and subtractive component 3 further includes a limiting unit. The limiting unit includes a limiting rod 122 rotatably connected to the first connecting end, and a limiting protrusion 124 and a limiting concave hole 125 arranged on the second connecting end. The limiting concave hole 125 is arranged between the two limiting protrusions 124, and after the limiting rod 122 is matched with the base body, it enters between the two limiting protrusions 124 and is connected to the limiting concave hole 125.

[0060] In some preferred embodiments, a connecting bolt 123 is arranged at the end of the limiting rod 122 far from the connecting rotating shaft 126 and extends outward. The connecting bolt 123 is threadedly connected to the limiting concave hole 125.

[0061] Thus, when the limiting rod 122 is matched with the base body and is close to the surface of the bracket 12, it can avoid the torsional deformation of the connecting bolt 123 side on the limiting rod 122 under the torque action of the rotating friction head or the milling cutter in the vertical plane, thereby ensuring the processing accuracy of friction additive manufacturing and mechanical subtractive manufacturing.

[0062] In some specific embodiments, the limiting rod 122 is rotatably connected to the bottom of the first connecting end. Correspondingly, the limiting concave hole 125 is arranged at the bottom of the second connecting end, so that the limiting rod 122 is connected to the base body along the X direction in the figure, with a regular structure and beautiful appearance.

[0063] Combined with Figure 5 As shown, in some preferred embodiments, limiting grooves 341 matched with the limiting rod 122 are respectively arranged at both ends in the width direction of the base body. In this embodiment, there is no limitation on the shapes of the limiting rod 122 and the limiting grooves 341. In some specific embodiments, the cross-sectional shapes of the limiting rod 122 and the limiting grooves 341 are rectangular, with a simple structure and easy processing.

[0064] In this embodiment, the surfaces of the limiting groove 341 and the limiting rod 122 are both precisely processed, and the surface roughness does not exceed 10 microns. The width of the limiting groove 341 is 5-10 microns larger than the width of the limiting rod 122, so as to ensure that the limiting rod 122 can smoothly enter or withdraw from the limiting groove 341.

[0065] In this embodiment, the limiting unit further includes a first fixing member, a second fixing member, and a connecting rotating shaft 126 connected to the first fixing member and the second fixing member respectively. The first fixing member and the second fixing member are oppositely arranged in the height direction on the first connection end, and the connecting rotating shaft 126 is rotatably connected to the limiting rod 122. It should be noted that the height direction in the figure is the direction of Z in the figure.

[0066] In this embodiment, there is no limitation on the structures of the first fixing member and the second fixing member. In some preferred embodiments, the cross-sectional shapes of the first fixing section and the second fixing member are rectangular, and the structure is simple.

[0067] Combined with Figure 7 As shown, in some preferred embodiments, the rotary friction head 32 includes a friction working end 321, a heat dissipation recess 323, and a heat dissipation protrusion 322, and the numbers of the heat dissipation protrusion 322 and the heat dissipation recess 323 are equal. The width l1 of the heat dissipation protrusion 322 is greater than or equal to the width l2 of the heat dissipation recess 323. Thus, the heat dissipation effect is good.

[0068] Combined with Figure 6-8 As shown, the embodiment of the present invention further provides a laser and friction composite additive and subtractive manufacturing method. Based on the above laser and friction composite additive and subtractive manufacturing device, it includes the following steps:

[0069] Step S1: Set the processing parameters of the part to be processed;

[0070] Step S2: Start the laser head 21 to make the laser focus irradiate the additive region of the part to form a molten pool, and start the powder feeding nozzle 22 to evenly send the metal powder into the molten pool in the additive region of the part to be processed to form an additive metal layer;

[0071] Step S3: Start the rotary friction head 32 to perform friction treatment on the surface of the additive metal layer on the part to be processed;

[0072] Step S4: Real-time monitor the size of the additive metal flash on the part to be processed. When the size of the additive metal flash exceeds the maximum limit of the surface roughness, turn off the rotary friction head 32, adjust the rotary base 34, and align the milling cutter 33 and the laser focus with the position where the additive metal flash is located;

[0073] Step S5: Start the laser head 21 to heat the additive metal flash and soften the additive metal flash;

[0074] Step S6: Start the milling cutter 33 to perform milling and cutting treatment on the deformed regions such as the heated additive metal flash until the surface roughness of the additive metal reaches the requirements again;

[0075] Step S7: Repeat step S2 to step S6, or repeat step S1 to step S6 until a predetermined workpiece is obtained, and then perform finish machining on the predetermined workpiece to obtain the workpiece.

[0076] The laser and friction composite additive and subtractive manufacturing method provided in this embodiment combines laser-assisted additive manufacturing, friction additive manufacturing, and mechanical subtractive manufacturing, reduces the residual stress and deformation of the additive metal, refines the grain structure, suppresses crack defects, effectively avoids the adverse effects of metal flash or deformation formed by friction additive manufacturing on the surface roughness, laser additive manufacturing stability and forming, and greatly improves the manufacturing efficiency, processing quality and accuracy.

[0077] To elaborate on the process characteristics of the laser and friction composite additive and subtractive manufacturing process in more detail, combined with Figure 7 the laser and friction composite additive and subtractive manufacturing process parameters of the workpiece to be processed are described as follows:

[0078] Processing parameters of the rotary friction head 32: the rotation speed V1 and feed speed V2 of the rotary friction head 32, and the relative position of the rotary friction head 32 and the part surface, i.e., the friction pressing depth H1;

[0079] Laser parameters: the feed speed of the laser beam is equal to the feed speed V2 of the rotary friction head 32, the relative position of the laser beam focus O and the part surface, i.e., the defocusing depth H2, and the horizontal distance L between the laser beam focus O and the center line of the rotary friction head 32 is determined by the dimensions of the bracket 12, the laser head 21 and the powder feeding nozzle 22;

[0080] Powder feeding parameters include powder feeding rate and powder particle size;

[0081] To elaborate on the process characteristics of mechanical subtractive manufacturing in more detail, combined with Figure 8 the mechanical subtractive manufacturing process parameters of the flash of the workpiece to be processed are described as follows:

[0082] Processing parameters of the milling cutter 33: the rotation speed V3 and feed speed V4 of the milling cutter 33, and the relative position of the milling cutter 33 and the part surface, i.e., the milling depth H3;

[0083] Laser parameters: the feed speed of the laser beam is equal to the feed speed V4 of the milling cutter 33, the relative position of the laser beam focus O and the part surface, i.e., the defocusing depth H4, and the horizontal distance L between the laser beam focus O and the center line of the milling cutter 33 remains unchanged.

[0084] It should be noted that those skilled in the art can determine the rotational speed V1 and feed speed V2 of the rotary friction head 32, the rotational speed V3 and feed speed V4 of the milling cutter 33, the friction pressing depth H1 and laser defocusing depth H2, the milling depth H3 and laser defocusing depth H4 according to factors such as the hardness of the metal to be added, the surface roughness of the processed surface after laser and friction-assisted additive manufacturing, the laser feed rate, the stiffness of the rotary friction head 32 and the milling cutter 33. For example, for the process parameters of the laser and friction-assisted additive manufacturing process, the rotational speed V1 of the rotary friction head 32 can be 50 - 1200 rpm, the feed speed V2 of the friction head and the laser head 21 can be 0.05 - 25 mm / s, the laser power can be 300 - 2000 W, the powder feeding rate can be 1.8 - 19 g / min, and the powder particle size can be 30 - 150 μm; for the process parameters of the mechanical subtractive manufacturing process, the rotational speed V3 of the milling cutter can be 150 - 2500 rpm, the feed speed V4 of the milling cutter and the laser head 21 can be 0.2 - 30 mm / s, and the laser power can be 50 - 600 W.

[0085] In this embodiment, step S4 includes: when the size of the additive metal flash exceeds the maximum limit of the surface roughness, turn off the rotary friction head 32, rotate the connection bolt 123 on the limit rod 122 in the second additive and subtractive assembly 3, and the limit rod 122 is disengaged from the limit concave hole 125 in the second additive and subtractive assembly 3 to realize the release of the limit rod 122; turn the limit rod 122 to the side away from the rotary base 34, and adjust the rotary base 34 to align the milling cutter 33 and the laser focus with the position where the additive metal flash is located. At this time, turn the limit rod 122 into the limit groove 341 of the rotary base 34 and tighten the connection bolt 123 so that the connection bolt 123 enters the limit concave hole 125 to realize the locking of the limit rod 122.

[0086] In this embodiment, step S7 includes: when additive manufacturing multiple layers of metal deposition structures on the surface of the workpiece to be processed, after completing the laser-assisted additive manufacturing, friction additive manufacturing and mechanical subtractive manufacturing of the first layer of metal, repeat steps S2 to S6;

[0087] When additive manufacturing gradient structure metal deposition structures on the surface of the workpiece to be processed, after completing the laser-assisted additive manufacturing, friction additive manufacturing and mechanical subtractive manufacturing of the first layer of metal, repeat steps S1 to S6.

[0088] It should be noted that when additive manufacturing a gradient structure metal deposition tissue on the surface of a workpiece to be processed, after the laser-assisted additive manufacturing, friction additive manufacturing, and mechanical subtractive manufacturing of the previous metal are completed, it is necessary to replace the elemental composition of the welding metal powder and timely adjust the processing parameters of the rotary friction head 32, laser parameters, relative position parameters between the rotary friction head 32 and the laser head 21, and powder feeding parameters to ensure good quality of the additive manufacturing gradient structure metal deposition tissue.

[0089] To further elaborate on the present invention, the present invention will be further described below in conjunction with specific embodiments. The methods used in the embodiments of the present invention are all conventional methods unless otherwise specified.

[0090] Embodiment 1

[0091] This embodiment provides a composite processing method for additive manufacturing a multi-layer metal deposition tissue on the surface of a workpiece to be processed based on a laser and friction composite additive and subtractive processing device, which specifically includes the following steps:

[0092] 1.1. Set the processing parameters of the part to be processed: the rotation speed V1 and feed speed V2 of the rotary friction head 32, the relative position between the rotary friction head 32 and the part surface, i.e., the friction pressing depth H1, the feed speed of the laser beam is equal to the feed speed V2 of the rotary friction head 32, the relative position between the laser beam focus O and the part surface, i.e., the defocus depth H2, the horizontal distance L between the laser beam focus O and the center line of the rotary friction head 32 is determined by the dimensions of the bracket 12, laser head 21, and powder feeding nozzle 22, the powder feeding rate and powder particle size. Among them, the laser head 21 is adjusted to move vertically relative to the bracket 12 by adjusting the adjustment knob 121 to adjust the friction pressing depth H1 and defocus depth H2;

[0093] 1.2. Start the laser head 21 to make the laser focus irradiate the area to be additively manufactured on the part to form a molten pool, and start the powder feeding nozzle 22 to evenly send the metal powder into the molten pool in the area to be additively manufactured on the part to be processed to form an additive metal layer;

[0094] 1.3. Start the rotary friction head 32 to perform friction treatment on the surface of the additive metal layer on the part to be processed;

[0095] 1.4. Real-time monitor the size of the additive metal burr on the part to be processed. When the size of the additive metal burr exceeds the maximum limit of the surface roughness, turn off the rotary friction head 32, and adjust the rotary base 34, set the rotation speed V3, feed speed V4, and milling depth H3 of the milling cutter 33; the feed speed of the laser beam is equal to the feed speed V4 of the milling cutter 33, the relative position between the laser beam focus O and the part surface, i.e., the defocus depth H4, the horizontal distance L between the laser beam focus O and the center line of the milling cutter 33 remains unchanged, and align the milling cutter 33 and the laser focus with the position where the additive metal burr is located;

[0096] 1.5. Start heating the additive metal flash by the laser head 21 to soften the additive metal flash.

[0097] 1.6. Start the milling cutter 33 to perform milling and cutting on the heated additive metal flash and other deformed areas until the surface roughness of the additive metal reaches the requirement again.

[0098] 1.7. Repeat step 1.2 to step 1.6, or repeat step 1.1 to step 1.6 until a predetermined workpiece is obtained, and perform finish machining on the predetermined workpiece to obtain the workpiece.

[0099] Among them, step 1.4 includes: when the size of the additive metal flash exceeds the maximum limit of the surface roughness, turn off the rotary friction head 32, rotate the connection bolt 123 on the limit rod 122 in the second additive and subtractive component 3, and the limit rod 122 is disengaged from the limit concave hole 125 in the second additive and subtractive component 3 to realize the release of the limit rod 122; turn the limit rod 122 to the side away from the rotary base 34, and adjust the rotary base 34 to align the milling cutter 33 and the laser focus with the position where the additive metal flash is located. At this time, turn the limit rod 122 into the limit groove 341 of the rotary base 34 and tighten the connection bolt 123 so that the connection bolt 123 enters the limit concave hole 125 to realize the locking of the limit rod 122.

[0100] Embodiment 2

[0101] This embodiment provides a composite processing method for additive manufacturing of gradient structure metal deposition tissue on the surface of a workpiece to be processed based on a laser and friction composite additive and subtractive processing device. The processing method provided in this embodiment is the same as the processing method in Embodiment 1, except that the last step adopts the following method:

[0102] After completing the laser-assisted additive, friction additive and mechanical subtractive processing of the first layer of metal, the laser and friction composite additive and subtractive processing device is lifted as a whole by a manipulator 46 by an average height of a deposition layer, and steps 1.1 to 1.6 are repeated, that is, after completing the laser-assisted additive, friction additive and mechanical subtractive processing of the previous metal, it is necessary to change the composition of the metal powder element and timely adjust the processing parameters of the rotary friction head 32, laser parameters, relative position parameters between the rotary friction head 32 and the laser head 21, and powder feeding parameters until a predetermined workpiece is obtained, and perform finish machining on the predetermined workpiece to obtain the workpiece.

[0103] Although the present disclosure is disclosed as above, the protection scope of the present disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and these changes and modifications will all fall within the protection scope of the present invention.

Claims

1. A laser and friction composite additive and subtractive manufacturing device, characterized in that Comprising: A frame body (1), a first additive and subtractive component (2) and a second additive and subtractive component (3), wherein The first additive and subtractive component (2) includes a laser head (21) and a powder feeding nozzle (22). A vertical guide rail is arranged on the side of the laser head (21). The powder feeding nozzle (22) is arranged at the end of the laser head (21) and is adapted to send metal powder to the laser focus of the additive laser source; The frame body (1) includes a support (11) and a bracket (12). The bracket (12) is vertically fixed on the support (11). The bracket (12) is arranged parallel to the laser head (21). A first motion unit adapted to cooperate with the guide rail is arranged on the side of the bracket (12). The first motion unit is slidably arranged on the guide rail to adjust the vertical movement of the laser head (21) relative to the bracket (12); The second additive and subtractive component (3) includes a driving motor (31), a milling cutter (33), a rotary friction head (32) and a rotary base (34). The rotary base (34) includes a base body and transmission gears (343) arranged at both ends of the base body in the height direction. The base body is rotatably connected to the bracket (12). The transmission gears (343) are used for driving connection with the driving motor (31). The transmission gears (343) are provided with mounting surfaces (344) for detachably connecting with the rotary friction head (32) or the milling cutter (33). The rotary friction head (32) and the milling cutter (33) are arranged parallel to the laser head (21), and the rotary friction head (32) and the milling cutter (33) are respectively arranged at both ends of the rotary base (34) in the height direction.

2. The laser and friction composite additive and subtractive manufacturing device according to claim 1, wherein The bracket (12) includes two relatively arranged connection ends, and the rotary base (34) is adapted to drive the rotary friction head (32) and the milling cutter (33) to rotate between the two connection ends; The rotary base (34) further includes a connecting shaft rod. Bearings (342) for rotatably connecting with the connecting shaft rod are arranged at both ends of the base body in the length direction. A through hole adapted to cooperate with the connecting shaft rod is arranged inside the base body. The connecting shaft rod is adapted to penetrate through the bearings (342) and the through hole and be connected between the two relatively arranged connection ends of the bracket (12).

3. The laser and friction composite additive and subtractive manufacturing device according to claim 2, characterized in that, The two relatively arranged connection ends of the bracket (12) include a first connection end and a second connection end. The second additive and subtractive component (3) further includes a limiting unit. The limiting unit includes a limiting rod (122) rotatably connected to the first connection end and a limiting protrusion (124) and a limiting concave hole (125) arranged on the second connection end. The limiting concave hole (125) is arranged between the two limiting protrusions (124), and after the limiting rod (122) cooperates with the base body, it enters between the two limiting protrusions (124) and is connected to the limiting concave hole (125).

4. The laser and friction composite additive and subtractive manufacturing device according to claim 3, wherein, Limiting grooves (341) adapted to cooperate with the limiting rod (122) are respectively arranged at both ends of the base body in the width direction.

5. The laser and friction composite additive and subtractive manufacturing device according to claim 3, wherein, The limiting unit further includes a first fixing member, a second fixing member, and a connecting rotating shaft (126) respectively connected to the first fixing member and the second fixing member. The first fixing member and the second fixing member are oppositely arranged in the height direction on the first connection end, and the connecting rotating shaft (126) is rotatably connected to the limiting rod (122).

6. The laser and friction composite additive and subtractive manufacturing device according to claim 5, wherein, A connecting bolt (123) extends outward from the end of the limiting rod (122) away from the connecting rotating shaft (126), and the connecting bolt (123) is threadedly connected to the limiting concave hole (125).

7. The laser and friction composite additive and subtractive manufacturing device according to claim 1, characterized in that An adjusting knob (121) connected to the first moving unit is further provided on the side surface of the bracket (12), and the adjusting knob (121) is adapted to adjust the vertical movement of the laser head (21) relative to the bracket (12).

8. A laser and friction composite additive and subtractive manufacturing method, characterized in that, Based on the laser and friction composite additive and subtractive manufacturing device according to any one of claims 1-7, the following steps are included: Step S1: Set the processing parameters of the part to be processed; Step S2: Start the laser head (21) to make the laser focus irradiate the additive region of the part to form a molten pool, and start the powder feeding nozzle (22) to evenly feed metal powder into the molten pool in the additive region of the part to be processed, forming an additive metal layer; Step S3: Start the rotary friction head (32) to perform friction treatment on the surface of the additive metal layer on the part to be processed; Step S4: Real-time monitor the size of the additive metal burr on the part to be processed. When the size of the additive metal burr exceeds the maximum limit of the surface roughness, turn off the rotary friction head (32), adjust the rotary base (34), and align the milling cutter (33) and the laser focus with the position where the additive metal burr is located; Step S5: Start the laser head (21) to heat the additive metal burr and soften the additive metal burr; Step S6: Start the milling cutter (33) to perform milling and cutting treatment on the deformed area of the heated additive metal burr until the surface roughness of the additive metal reaches the requirement again; Step S7: Repeat Step S2 to Step S6, or repeat Step S1 to Step S6 until a predetermined workpiece is obtained, and perform finish machining on the predetermined workpiece to obtain the workpiece.

9. The laser and friction composite additive and subtractive manufacturing method according to claim 8, characterized in that The Step S4 includes: When the size of the additive metal burr exceeds the maximum limit of the surface roughness, turn off the rotary friction head (32), rotate the connecting bolt (123) on the limiting rod (122) in the second additive and subtractive component (3), and the limiting rod (122) disengages from the limiting concave hole (125) in the second additive and subtractive component (3) to realize the release of the limiting rod (122); turn the limiting rod (122) to the side away from the rotary base (34), adjust the rotary base (34), align the milling cutter (33) and the laser focus with the position where the additive metal burr is located, at this time turn the limiting rod (122) into the limiting groove (341) of the rotary base (34), and tighten the connecting bolt (123) so that the connecting bolt (123) enters the limiting concave hole (125) to realize the locking of the limiting rod (122).

Images