Aluminum magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device and method

Abstract

The invention discloses an aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device and method, and relates to the technical field of alloy additive manufacturing, the aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device comprises a forging body connected to a 3D printer, and the forging body and a 3D printing head are arranged at an interval; the forging needle corresponds to the forging area and is movably arranged at the bottom of the forging body in the forging direction; and the amplitude-change pole is arranged in the forging body and driven by the ultrasonic driving device to reciprocate in the direction close to the forging needle and away from the forging needle, the forging needle is driven by the amplitude-change pole to hit the forging area in the forging direction, and the forging needle is reset through the fixing spring after hitting. The ultrasonic micro-forging head can be in synchronous linkage with the 3D printing powder feeding head and the wire feeding head, and hole defects and brittle phase textures can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of alloy additive manufacturing, and in particular to an aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device and method. Background Art

[0002] Aluminum-magnesium alloys are widely used in the automotive, aerospace and other fields due to their light weight and high strength. Aluminum-magnesium alloy 3D printing is a technology that uses metal powder to form metal components. Its forming quality is restricted. One of the restrictions is serious pore defects. The magnesium element in the aluminum-magnesium alloy is easy to vaporize during the 3D printing process, and a large number of vaporization pore defects are formed after the molten pool solidifies. At the same time, the high aluminum content causes hydrogen to dissolve in the molten pool, which easily causes hydrogen pores to form after the molten pool solidifies. Another restriction is that aluminum and magnesium elements will form a continuous network of Al17Mg12 brittle phase texture.

[0003] In the prior art, patent CN106735200B proposes an ultrasonic vibration hammering device for releasing the thermal stress generated during the solidification process of the melt to achieve the effect of suppressing pores. Patent CN107244072A proposes applying ultrasonic forging on the melt through a forging head. Patent CN116713558A proposes rolling on the melt through a roller. The above prior art can effectively improve the printing quality by causing plastic deformation on the melt through forging force or pressure, and can optimize the above constraints to a certain extent, but the following problems still exist:

[0004] 1) Low-power ultrasonic hammering is difficult to bridge the deep subcutaneous vaporization holes and hydrogen pore defects of aluminum-magnesium alloys and improve the brittle phase texture;

[0005] 2) The ultrasonic forging head is flat or V-shaped with a sharp tip and is in rigid contact with the melt channel, which is not conducive to the movement of the forging head on the rough melt channel and may even scratch the melt channel and affect the printing quality;

[0006] 3) The ultrasonic forging head is large in size and the ultrasonic equipment can only perform simple trajectory motion such as linear translation, which is difficult to apply to curved trajectory motion such as large curvature radius. Therefore, it has not yet been able to synchronize with the 3D printing powder feeding head, wire feeding head, etc.;

[0007] 4) Although roller forging solves the problem of the forging head scratching the melt channel, it can only perform simple linear translation or regular motion with a small curvature radius, and it is still difficult to achieve curved trajectory motion such as the melt channel rotation point or large curvature radius; therefore, roller forging cannot be synchronized with 3D printing powder feeding heads, wire feeding heads, etc.

[0008] In view of this, how to provide an aluminum-magnesium alloy 3D printing device that can be synchronously linked with a 3D printing powder feeding head, a wire feeding head, etc. and can improve hole defects and brittle phase texture is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0009] The purpose of the present invention is to provide an aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device and method to solve the problems existing in the prior art.

[0010] To achieve the above-mentioned purpose, the present invention provides an aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device, comprising:

[0011] A forging body, connected to the 3D printer and spaced apart from the 3D printing head;

[0012] A forging needle, corresponding to the forging area and movably arranged at the bottom of the forging body along the forging direction;

[0013] The horn is arranged in the forging body and is driven by the ultrasonic driving device to reciprocate in the direction close to the forging needle and away from the forging needle. The forging needle is driven by the horn to hit the forging area in the forging direction and is reset by the fixed spring after hitting.

[0014] A preload spring is arranged on the top of the forging body and is used to provide a downward preload force to the forging body.

[0015] Furthermore, a limiting piece is arranged near the top of the forging needle, and the fixing spring is sleeved outside the forging needle and located between the limiting piece and the forging body. When the forging needle hits the forging area along the forging direction, the fixing spring is compressed.

[0016] Furthermore, the bottom of the forging needle is a pointed tip, and the lower surface of the pointed tip is a curved surface with a curvature of 1 / 10 to 1 / 3 mm. -1 ; The cross-sectional diameter of the forging needle is 3 to 10 mm.

[0017] Furthermore, the length of the forging needle outside the forging body is 1.5 to 20 mm.

[0018] Furthermore, the distance between the tip and the center of the 3D printing head is 0.5 to 5 cm.

[0019] Furthermore, the angle between the forging body and the length direction of the 3D printing head is greater than 0 and less than or equal to 30°, and the cross-sectional diameter of the forging body is 20 to 100 mm.

[0020] Furthermore, the ultrasonic power of the ultrasonic driving device is 100-1000W, and the ultrasonic frequency is 5-50kHz.

[0021] The present invention also provides an aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing method, which uses the aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device, including the following steps: connecting the forging body to a 3D printer and arranging it at a distance from the 3D printing head, the 3D printer drives the 3D printing head and the forging body to move synchronously, and during the movement, the preload spring provides a downward preload force to the forging body, and the ultrasonic driving device drives the amplitude variable rod to reciprocate, and the amplitude variable rod drives the forging needle in the forging body to hit the forging area, and after the hitting, the forging needle is reset by the fixing spring.

[0022] The present invention discloses the following technical effects:

[0023] The present invention provides an ultrasonic micro-forging head adapted to the size of a 3D printer. The ultrasonic micro-forging head is composed of a forging body, a forging needle and a horn and is connected to the 3D printer so that the ultrasonic micro-forging head moves synchronously with the 3D printing head. In terms of structure, it can realize free movement on the solidification melt channel in the additive manufacturing process without being hindered by the convex and concave surface, or affecting the printing organization and material performance due to scratching the surface. At the same time, the small-sized forging head can be set with the 3D printing head (powder feeding or wire feeding head) in a small spacing and small inclination angle, so that the effect of applying a large forging force can be achieved. In terms of function, the ultrasonic micro-forging head can move synchronously with the 3D printing head, and can realize the trajectory movement of complex curves such as rotation and large curvature radius, and realize the synchronous linkage with the additive manufacturing 3D printing head to form parts. In terms of product performance, it can greatly bridge the hole defects of aluminum-magnesium alloys to improve the product forming density, improve the brittle phase texture and homogenize the forming organization, and improve the performance of 3D printed components. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the structure of the present invention;

[0026] Among them, 1. preload spring; 2. forging body; 3. amplitude rod; 4. fixed spring; 5. forging needle; 6. follow-up connecting frame; 7. swivel sleeve; 8. rotating joint; 9. fixed sleeve; 10. 3D printing head. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Example 1

[0030] The embodiment of the present invention provides an aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device, which is used for aluminum-magnesium alloy powder feeding 3D printing, the forging body 2 is connected to the 3D printer and is spaced apart from the 3D printing head 10 (powder feeding head), the 3D printing head 10 is vertically arranged, and the forging body 2 is tiltedly arranged on one side of the 3D printing head 10, specifically, the angle between the forging body 2 and the vertical direction is 10°, and the distance between the tip of the forging needle 5 and the center of the 3D printing head 10 is 2cm. The forging needle 5 corresponds to the forging area and is movably arranged at the bottom of the forging body 2 along the forging direction, the amplitude rod 3 is arranged in the forging body 2 and is driven by the ultrasonic driving device to reciprocate in the direction close to the forging needle 5 and away from the forging needle 5, and the forging needle 5 is driven by the amplitude rod 3 to hit the forging area along the forging direction, and is reset by the fixed spring 4 after hitting. The lower end of the preload spring 1 is arranged on the top of the forging body 2, and the upper end is connected to a pressure mechanism or other structure that can be used to provide preload force, so as to provide downward preload force to the forging body 2. In this embodiment, the preload force is 500N.

[0031] In this embodiment, a fixed sleeve 9 is sleeved on the outer surface of the 3D printing head 10, and the fixed sleeve 9 is connected to the rotating sleeve 7 through a rotating connecting piece such as a bearing. The rotating sleeve 7 is connected to one end of a rotating joint 8, and the other end of the rotating joint 8 is connected to the forging body 2 through a follower connecting frame 6. The follower connecting frame 6 is only used to limit the forging body 2, and the forging body 2 can move in the up and down directions.

[0032] In this embodiment, a limit piece is provided near the top of the forging needle 5, and the limit piece extends from the forging needle 5 to both sides and is symmetrically arranged. The fixed spring 4 is sleeved outside the forging needle 5 and is located between the limit piece and the forging body 2. The upper surface of the fixed spring 4 is limited by the lower surface of the limit piece, and the lower surface of the fixed spring 4 is connected to the bottom of the forging body 2. The bottom of the forging body 2 is provided with a through hole for the reciprocating movement of the forging needle 5. The outer diameter of the fixed spring 4 is larger than the inner diameter of the through hole. When the forging needle 5 hits the forging area along the forging direction, the limit piece squeezes the spring downward, and the fixed spring 4 is compressed to generate upward elastic potential energy. After the forging needle 5 hits the forging area, the amplitude transformer 3 is driven to reset by the ultrasonic driving device, and the forging needle 5 is assisted in resetting by the fixed spring 4.

[0033] In this embodiment, the bottom of the forging needle 5 is a pointed tip, and the lower surface of the pointed tip is a curved surface with a curvature of 1 / 5 mm. -1 The cross-sectional diameter of the forging needle 5 is 5 mm, and the length of the forging needle 5 outside the forging body 2 is 3 mm. The cross-sectional diameter of the forging body 2 is 30 mm, the ultrasonic power of the ultrasonic driving device is 200 W, and the ultrasonic frequency is 20 kHz.

[0034] An embodiment of the present invention also provides an aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing method, which uses the above-mentioned aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device, including the following steps: connecting the forging body 2 to the 3D printer and setting it at an interval with the 3D printing head 10, the 3D printer drives the 3D printing head 10 and the forging body 2 to move synchronously, and during the movement, the preload spring 1 provides a downward preload force to the forging body 2, and the ultrasonic drive device drives the amplitude change rod 3 to move back and forth, and the amplitude change rod 3 drives the forging needle 5 in the forging body 2 to hit the forging area. After the impact, the forging needle 5 is reset by the fixing spring 4; the forging needle 5 continuously acts on the dynamically solidified weld to apply ultrasonic micro-forging treatment, and continues to ultrasonic until the printing is completed to form a part.

[0035] The quality inspection of the formed aluminum-magnesium alloy parts showed that the microstructure of the aluminum-magnesium alloy parts was uniform, the pore defects were significantly reduced, the density was greatly improved, the yield strength was increased by 20%, the ultimate tensile strength was increased by 8%, and the elongation was increased by 13.4%.

[0036] Example 2

[0037] The difference between this embodiment and embodiment 1 is that it is used for aluminum-magnesium alloy powder feeding 3D printing. The quality test of the formed aluminum-magnesium alloy parts shows that the aluminum-magnesium alloy parts have uniform microstructure, significantly reduced hole defects, greatly improved density, 21% increased yield strength, 7% increased ultimate tensile strength, and 12.8% increased elongation.

[0038] Comparative Example 1

[0039] The difference between Comparative Example 1 and Example 1 is that the ultrasonic micro-forging head (consisting of a forging body 2, a forging needle 5 and a horn 3) is replaced by an existing stepped ultrasonic probe, whose tip is a plane, and the distance between the stepped ultrasonic probe and the 3D printing head 10 is greater than 5 cm, and the angle between the stepped ultrasonic probe and the vertical direction is greater than 30°.

[0040] Quality inspection of the formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, and no significant change in the mechanical properties.

[0041] Comparative Example 2

[0042] The difference between Comparative Example 2 and Example 1 is that the curvature of the lower surface of the tip is 1 / 2 -1 , the cross-sectional diameter of the forging needle 5 is 2 mm.

[0043] Quality inspection of formed aluminum-magnesium alloy parts showed an increase in hole defects, a 2% decrease in yield strength, a 3% decrease in ultimate tensile strength, and a 2.5% increase in elongation.

[0044] Comparative Example 3

[0045] The difference between Comparative Example 3 and Example 1 is that the curvature of the lower surface of the tip is 1 / 15 -1 The cross-sectional diameter of the forging needle 5 is 15 mm.

[0046] Quality inspection of formed aluminum-magnesium alloy parts showed that the porosity was reduced, the yield strength was increased by 3%, the ultimate tensile strength was increased by 2%, and the elongation was increased by 2.2%.

[0047] Comparative Example 4

[0048] The difference between Comparative Example 4 and Example 1 is that the length of the forging needle 5 outside the forging body 2 is 1 mm.

[0049] Quality inspection of formed aluminum-magnesium alloy parts showed that hole defects were reduced, yield strength increased by 1%, ultimate tensile strength increased by 1.4%, and elongation increased by 2.2%.

[0050] Comparative Example 5

[0051] The difference between Comparative Example 5 and Example 1 is that the length of the forging needle 5 outside the forging body 2 is 25 mm.

[0052] The quality inspection of the formed aluminum-magnesium alloy parts showed that the microstructure was relatively uniform, the hole defects were reduced, the density was improved, the yield strength was increased by 10%, the ultimate tensile strength was increased by 3.5%, and the elongation was increased by 6.3%. However, during the printing process, the forging needle 5 was prone to deflection and breakage.

[0053] Comparative Example 6

[0054] The difference between Comparative Example 6 and Example 1 is that the distance between the tip of the forging needle 5 and the center of the 3D printing head 10 is 0.4 cm.

[0055] Quality inspection of the formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, and no significant change in the mechanical properties.

[0056] Comparative Example 7

[0057] The difference between Comparative Example 7 and Example 1 is that the distance between the tip of the forging needle 5 and the center of the 3D printing head 10 is 6 cm.

[0058] Quality inspection of formed aluminum-magnesium alloy parts showed poor microstructural uniformity, reduced pores, and no significant changes in yield strength and elongation.

[0059] Comparative Example 8

[0060] The difference between Comparative Example 8 and Example 1 is that the angle between the forging body 2 and the vertical direction is 50°, and the cross-sectional diameter of the forging body 2 is 15 mm.

[0061] Quality inspection of the formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, and no significant change in the mechanical properties.

[0062] Comparative Example 9

[0063] The difference between Comparative Example 9 and Example 1 is that the angle between the forging body 2 and the vertical direction is 80°, and the cross-sectional diameter of the forging body 2 is 110 mm.

[0064] Quality inspection of the formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, and no significant change in the mechanical properties.

[0065] Comparative Example 10

[0066] The difference between Comparative Example 10 and Example 1 is that the ultrasonic power is 30 W and the ultrasonic frequency is 2 kHz.

[0067] Quality inspection of the formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, and no significant change in the mechanical properties.

[0068] Comparative Example 11

[0069] The difference between Comparative Example 11 and Example 1 is that the ultrasonic power is 1050 W and the ultrasonic frequency is 60 kHz.

[0070] Quality inspection of formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, a 15% increase in yield strength, a 5% increase in ultimate tensile strength, and a 3.3% increase in elongation.

[0071] Comparative Example 12

[0072] The difference between Comparative Example 12 and Example 1 is that the preload force is 3N.

[0073] Quality inspection of the formed aluminum-magnesium alloy parts showed that there was no improvement in the brittle phase texture, obvious hole defects, and no significant change in the mechanical properties.

[0074] Comparative Example 13

[0075] The difference between Comparative Example 13 and Example 1 is that the preload force is 1500N.

[0076] Quality inspection of the formed aluminum-magnesium alloy parts showed that the structure showed obvious linear texture, hole defects were significantly reduced, density was greatly improved, yield strength was increased by 15%, ultimate tensile strength was increased by 5%, and elongation was increased by 2.6%.

[0077] The mechanical properties test results of Example 1, Example 2 and various comparative examples are shown in the following table:

[0078]

[0079]

[0080] It can be seen from the above table that compared with the comparative examples, Examples 1 and 2 can significantly improve the mechanical properties of the aluminum-magnesium alloy, and the forging head structure, the shape of the forging needle 5, the curvature of the tip of the forging needle 5, the cross-sectional diameter of the forging needle 5, the length of the forging needle 5 outside the forging body 2, the center distance between the forging needle 5 and the 3D printing head, the cross-sectional diameter of the forging body 2, the inclination angle of the forging body 2, the ultrasonic power frequency, and the pressing force all have an influence on the mechanical properties of the formed component.

[0081] The aluminum-magnesium alloy obtained in Comparative Example 11 is closest to that in Example 1 and Example 2 in terms of mechanical properties, but the elongation is quite different, and the energy consumption is significantly increased, the brittle phase texture is not improved, and the hole defects are obvious. The mechanical properties of the remaining comparative examples are quite different from those of Example 1 and Example 2.

[0082] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0083] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device, characterized in that: include: A forging body (2) is connected to the 3D printer and is spaced apart from the 3D printing head (10); A forging needle (5) is arranged at the bottom of the forging body (2) corresponding to the forging area and movably along the forging direction; A horn (3) is arranged in the forging body (2) and is driven by an ultrasonic driving device to reciprocate in a direction close to the forging needle (5) and away from the forging needle (5). The forging needle (5) is driven by the horn (3) to strike the forging area in the forging direction and is reset by a fixing spring (4) after striking. A preload spring (1) is arranged on the top of the forged body (2) and is used to provide a downward preload force to the forged body (2).

2. The aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device according to claim 1, characterized in that: The forging needle (5) is provided with a limiting piece near its top, and the fixing spring (4) is sleeved outside the forging needle (5) and located between the limiting piece and the forging body (2). When the forging needle (5) strikes the forging area along the forging direction, the fixing spring (4) is compressed.

3. The aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device according to claim 1 is characterized in that: The bottom of the forging needle (5) is a pointed tip, and the lower surface of the pointed tip is a curved surface with a curvature of 1 / 10 to 1 / 3 mm. -1 The cross-sectional diameter of the forging needle (5) is 3 to 10 mm.

4. The aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device according to claim 3 is characterized in that: The length of the forging needle (5) outside the forging body (2) is 1.5 to 20 mm.

5. The aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device according to claim 4, characterized in that: The distance between the tip and the center of the 3D printing head (10) is 0.5 to 5 cm.

6. The aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device according to claim 5, characterized in that: The angle between the forged body (2) and the length direction of the 3D printing head (10) is greater than 0 and less than or equal to 30°, and the cross-sectional diameter of the forged body (2) is 20 to 100 mm.

7. The aluminum-magnesium alloy ultrasonic micro-forging linked 3D printing additive manufacturing device according to claim 1, characterized in that: The ultrasonic power of the ultrasonic driving device is 100-1000W, and the ultrasonic frequency is 5-50kHz.

8. A method for additive manufacturing of aluminum-magnesium alloy by ultrasonic micro-forging and 3D printing, characterized in that: The aluminum-magnesium alloy ultrasonic micro-forging linkage 3D printing additive manufacturing device according to any one of claims 1 to 7 comprises the following steps: The forging body (2) is connected to a 3D printer and spaced apart from a 3D printing head (10). The 3D printer drives the 3D printing head (10) and the forging body (2) to move synchronously. During the movement, the preload spring (1) provides a downward preload force to the forging body (2). The ultrasonic drive device drives the amplitude changer (3) to move back and forth. The amplitude changer (3) drives the forging needle (5) in the forging body (2) to strike the forging area. After the striking, the forging needle (5) is reset by the fixing spring (4).

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