3D printing energy-absorbing device and manufacturing method

Abstract

The application discloses a 3D printing bearing energy-absorbing device and a manufacturing method. The device comprises one or more disc spring-like flexible structures arranged on a part bottom plate, wherein the disc spring-like flexible structure is formed by stacking a plurality of disc springs; the disc spring-like flexible structure comprises a disc spring stand column; the disc spring and the disc spring stand column are connected by a first support component; and the first support component plays a supporting role during 3D printing of the disc spring-like flexible structure. The manufacturing method is used for manufacturing the device. The application has the advantages of simple structure, simple manufacturing, good energy-absorbing effect and the like.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the technical field of energy absorption devices, in particular to a bearing energy absorption device based on 3D printing and a manufacturing method. BACKGROUND

[0002] "impact" is one of the most common loads that parts need to withstand in mechanical movement, including shock waves caused by air or underwater explosions, ballistic impact, and collision between objects. Some parts that often bear large impact loads have very high requirements for the impact resistance of the materials. Some complex material structures, such as lattice structures, have certain resistance to impact loads; however, these structures are often designed to be too complex, and traditional processing methods for processing such parts consume a lot of time and cost, or even cannot be processed.

[0003] 3D printing, as a new emerging additive processing method, has strong free-forming capability, and its processing technology and part structure complexity are weakly related, which has great advantages in solving the manufacturability of complex part structures, and is an important means to improve the impact resistance of parts. With the development of 3D printing, people try to use 3D printing technology to print some structures with impact resistance into the material in the form of units, so that the parts have corresponding impact resistance, thereby realizing the structural and functional integration of the part structure.

[0004] Currently, the 3D printing unit structures with impact resistance in the prior art mainly include metal foam structures and lattice structures.

[0005] For example, John W of Harvard University compared and analyzed the impact resistance of honeycomb sandwich structures and solid structures, studied the impact resistance of honeycomb structures in air and underwater environments, and studied the energy absorption capacity, shear resistance and strength of the two structures. It is found that the honeycomb structure can withstand more than twice the water impact under the same mass.

[0006] For example, P.K.Pinnoji et al. of the Department of Applied Mechanics, Indian Institute of Technology Delhi, New Delhi, India, compared and analyzed the impact resistance of low-density metal foam structures and ABS shell helmets by finite element analysis and experiments in order to reduce the weight of motorcycle helmets. The experimental results show that the low-density metal foam structure has a large plastic deformation in the impact area, and the impact force on the head and the peak acceleration of the head are lower than those of ABS. Compared with the ABS helmet with the same density, the low-density metal foam structure helmet reduces the normal stress on the head by about 25% and 22% respectively.

[0007] For example, A. Kumar of the University of Texas, USA, studied the influence of different foam structure types, different hole units and different porosities on the performance of the scaffold for human tissue regeneration, and verified the mechanical properties by experiment. Finally, it is found that the use of gradient porosity can achieve a more substantial lightweight of the scaffold structure under the premise of ensuring higher impact absorption capacity and tensile and compressive properties.

[0008] For example, P. Pinto of the University of Minho, Portugal, compared and analyzed the performance difference between single-size and double-size aluminum foam structures. Non-metallic structure prototypes of the two kinds of aluminum foam structures were printed by 3D technology, and then the final metal structures were processed by casting. Through compression test of the two structures, it is found that compared with single-size aluminum foam structure, the stiffness of double-size aluminum foam structure is increased by 29%, the compression strength is increased by 83%, and the energy absorption capacity is increased by more than 27%. Metal foam structure has excellent impact resistance. However, metal foam structure belongs to a non-periodic distributed structure, and there is a general phenomenon of uneven material distribution, which leads to unstable local strength and modulus, and is not suitable for occasions with high strength and stability requirements. In addition, the 3D printing manufacturability of metal foam structure is poor, and generally a non-metallic mold of the part needs to be printed first, and then the part is processed by investment casting.

[0009] Among the many 3D printed unit structures with impact resistance, there are many kinds of dot matrix structures, including cylindrical dot matrix structure, body-centered cubic dot matrix structure, face-centered cubic dot matrix structure Kagome dot matrix structure, etc. Some practitioners have conducted a lot of research on the impact resistance of dot matrix structure. Through research, some dot matrix structures such as Kagome structure have excellent strength and energy absorption capacity. However, dot matrix structure belongs to a rigid structure with small elastic deformation, which generally consumes impact energy through its own plastic deformation and structure damage, and is mainly used for disposable protective parts. SUMMARY

[0010] The technical problem to be solved by the present application is to provide a 3D printed bearing energy absorption device and a manufacturing method with simple structure, easy manufacturing and good energy absorption effect.

[0011] To solve the above technical problems, the present application adopts the following technical scheme:

[0012] A 3D printed bearing energy absorption device, comprising one or more disc spring-like flexible structures arranged on a part bottom plate, wherein the disc spring-like flexible structure is composed of a plurality of disc springs stacked together; the disc spring-like flexible structure comprises a disc spring column, and the disc spring and the disc spring column are connected by a first support part, which plays a supporting role during 3D printing of the disc spring-like flexible structure.

[0013] As a further improvement of the above device: the upper part of the disc spring-like flexible structure is provided with a part upper plate, and the disc spring column is connected between the part upper plate and the part bottom plate.

[0014] As a further improvement of the above device: the disc spring is connected with the part upper plate by a ring-shaped support component, which plays a supporting role in the 3D printing process and will be damaged after being deformed under stress.

[0015] As a further improvement of the above device: when there are multiple disc spring-like flexible structures, the disc spring-like flexible structures are arranged on the part bottom plate and arranged periodically with a center distance L.

[0016] As a further improvement of the above device: the suspended areas between the disc spring-like flexible structures are connected by a second support component, which plays a supporting role in the 3D printing process and will be damaged after being deformed under stress.

[0017] As a further improvement of the above device: the second support component is a columnar support component or a tree-shaped support component.

[0018] As a further improvement of the above device: the growth angle of the disc spring in the disc spring-like flexible structure is Φ, the interval between two disc springs is Δd1, and the distance between the disc spring and the part upper plate is Δd2.

[0019] The application further provides a method for manufacturing the 3D printing bearing energy absorption device.

[0020] Step S1: sintering the 3D printing bearing energy absorption device by 3D printing;

[0021] Step S2: hitting the combined disc spring unit to damage the first support component.

[0022] As a further improvement of the above manufacturing method: the growth angle of the disc spring in the disc spring-like flexible structure is Φ, the interval between two disc springs is Δd1, and the distance between the disc spring and the part upper plate is Δd2.

[0023] As a further improvement of the above manufacturing method: the Φ is any one of 20°, 25°, 30°, 35°, 40°, and 45°, the Δd1 is any one of 0.3mm, 0.4mm, and 0.5mm, and the Δd2 is any one of 0.3mm, 0.4mm, and 0.5mm.

[0024] Compared with the prior art, the application has the following advantages:

[0025] The 3D printing energy absorption device and manufacturing method have simple structure, simple manufacturing, and good energy absorption effect, and based on the excellent impact absorption and energy dissipation capacity of the combined disc spring, the combined disc spring is introduced as a 3D printing flexible structure functional unit, and good impact resistance of the 3D printing part is realized. The combined disc spring unit adopted by the present application meets the manufacturability process requirements of 3D printing, and can meet the manufacturability requirements of 3D printing by using small support based on 3D printing, and is manufactured at one time. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a structural principle schematic diagram of the 3D printing energy absorption device of the present application.

[0027] Figure 2 is a structural principle schematic diagram of the 3D printing energy absorption device of the present application from another perspective.

[0028] Figure 3 is a sectional schematic diagram of the 3D printing energy absorption device of the present application.

[0029] Figure 4 is a top view schematic diagram of the combined disc spring unit arranged on the part bottom plate in a specific application example of the present application.

[0030] Figure 5 is a three-dimensional schematic diagram of the combined disc spring unit arranged on the part bottom plate in a specific application example of the present application.

[0031] Figure 6 is a performance curve diagram of the energy absorption device of the present application in a specific test.

[0032] LEGEND:

[0033] 1, part bottom plate; 2, part upper plate; 3, disc spring-like flexible structure; 4, disc spring; 5, first support part; 6, annular support part; 7, disc spring column. DETAILED DESCRIPTION

[0034] The present application will be further described in detail below in combination with the drawings and specific examples of the present application.

[0035] The disc spring is a special spring that is conical in the axial direction and bears load, and stores a certain potential energy after bearing load deformation. The disc spring bears a large load in a small space, and compared with other types of springs, the disc spring has larger deformation energy per unit volume, has good shock absorption and shock absorption capacity, and especially after the combined disc spring is formed by stacking and combining, the surface friction resistance effect is more significant.

[0036] Based on the excellent impact absorption and energy dissipation ability of the combined disc spring, the combined disc spring is introduced as a functional unit of the 3D printing flexible structure to realize the impact resistance of the 3D printing part. However, the combined disc spring belongs to the assembly of parts, and it is difficult to be processed at one time by using 3D printing. Further based on the manufacturability process requirement of 3D printing, the weak and small support structure based on 3D printing is proposed to realize the combined disc spring unit meeting the manufacturability requirement of 3D printing.

[0037] As shown in Figures 1-5 , the 3D printing bearing energy absorption device of the application comprises one or more disc spring-like flexible structures 3 arranged on a part bottom plate 1, the disc spring-like flexible structure 3 is composed of a plurality of disc springs 4, and the number of disc springs 4 can be changed according to the height of the part; the disc spring-like flexible structure 3 of the application further comprises a disc spring column 7, and the disc spring 4 and the disc spring column 7 are connected by a first support part 5. The first support part 5 is a weak and small columnar support. The first support part 5 plays a supporting role during 3D printing of the disc spring-like flexible structure 3, and is destroyed and disappears under external force.

[0038] In a specific application example, the growth angle of the disc spring 4 itself is Φ, the interval between the two disc springs 4 is Δd1, and the interval between the disc spring 4 and the part upper plate 2 is Δd2.

[0039] In this embodiment, the disc spring-like flexible structure 3 is provided with a part upper plate 2 above, and the disc spring column 7 is connected between the part upper plate 2 and the part bottom plate 1.

[0040] In this embodiment, the disc spring 4 and the part upper plate 2 are connected by a ring-shaped support part. This ring-shaped support part belongs to a weak and small support, and its supporting strength is very small. It only plays a supporting role during 3D printing, and will be damaged after deformation under stress. Therefore, the disc spring-like flexible structure 3 forms an assembly composed of a plurality of disc springs 4.

[0041] Referring to Figure 4 and Figure 5 , in this embodiment, when the disc spring-like flexible structure 3 is multiple, in order to meet the manufacturability requirement of 3D printing, the disc spring-like flexible structures 3 are arranged on the part bottom plate 1 with a center distance L.

[0042] In this embodiment, the second support part is used to connect the places with too large suspended area between the disc spring-like flexible structures 3. The second support part is a columnar support part, or a tree-shaped part, or other weak and small support parts. On this basis, the application designs and simulates a plurality of layout schemes, and verifies them by combining with the unit application characteristic design experiment to confirm the basic characteristics of the structure.

[0043] The application further provides a manufacturing method of the 3D printing bearing energy absorption device, and steps of the method comprise:

[0044] Step S1: forming the 3D printing bearing energy absorption device (combined disc spring unit) by 3D printing sintering;

[0045] Selecting Φ as 20°, 25°, 30°, 35°, 40°, 45°, and Δd1 and Δd2 as 0.3 mm, 0.4 mm and 0.5 mm respectively to perform orthogonal test.

[0046] Step S2: hammering the disc spring-like flexible structure 3 (combined disc spring unit) by artificial or equipment;

[0047] Based on engineering requirements, the smaller the growth angle Φ of the disc spring 4, the smaller the spacing Δd1 between the disc springs 4 and the spacing Δd2 between the springs and the upper plate 2 of the part, the stronger the bearing capacity and vibration absorption capacity of the disc spring 4, and the more favorable to the part. However, Φ, Δd1 and Δd2 are limited by the requirements of 3D printing manufacturability process, and too small angle will cause processing defects and affect the performance of the disc spring 4. Too small spacing will cause the disc springs 4 to be connected together.

[0048] In a specific application example, the combined disc spring unit sintered by SLM has good processing effect when Φ≥35°. The combined disc spring unit is disassembled, that is, the combined disc spring unit is hammered by artificial hammering. When Δd1=0.3, 0.4, 0.5, the columnar small support is damaged after being hammered, and the disc spring 4 is easily disassembled. When Δd2=0.5 mm, the annular small support is damaged after being hammered, and the disc spring 4 is easily disassembled.

[0049] In a specific application test, the mechanical property test uses a WDW-100 type microcomputer control electronic universal material testing machine to analyze the mechanical properties of the elastic damping unit, and the maximum test force can reach 100 kN; the measurement accuracy is high, the test machine accuracy reaches ±1%, and the displacement resolution is 0.01 mm; the operation is simple, and the control accuracy is high. The test sample of the application is fixed on the platform of the testing machine, and the load and displacement data are zeroed by the test system. The whole test is carried out in a room temperature environment, the loading speed of the upper chuck is set to 0.5 mm / min, the loading is continuously carried out until the sample is damaged, and the computer records the load P and displacement ΔL of the sample. Then the test data is processed and analyzed.

[0050] According to the 3D printing process parameters of the disc spring combined unit, when Φ=35°, Δd1=0.3 mm and Δd2=0.5 mm, the disc spring has the optimal effect, and the elastic deformation curve should be close to the strain curve of the disc spring of the same size. The disc spring performance curve is as follows: Figure 6As shown, the compressive yield strength thereof is about 300 MPa, and the maximum elastic compressive displacement is 2 mm.

[0051] The above are only preferred embodiments of the present application, and the protection scope of the present application is not limited to the above-mentioned embodiments. Any technical scheme falling within the concept of the present application shall fall within the protection scope of the present application. It should be noted that, for ordinary skilled in the art, some improvements and refinements without departing from the principles of the present application shall be considered as the protection scope of the present application.

Claims

1. A 3D-printed load-bearing energy-absorbing device, characterized in that: The system includes one or more disc spring-like flexible structures (3) arranged on the base plate (1) of the part. The disc spring-like flexible structure (3) is composed of multiple disc springs (4) stacked together. The disc spring-like flexible structure (3) includes a disc spring column (7). The disc springs (4) and the disc spring column (7) are connected by a first support component (5). The first support component (5) plays a supporting role when the disc spring-like flexible structure (3) is 3D printed. The upper part plate (2) is provided above the disc spring flexible structure (3), and the disc spring column (7) is connected between the upper part plate (2) and the bottom part plate (1). The disc spring (4) is connected to the upper plate (2) of the part by a ring-shaped support component. The ring-shaped support component plays a supporting role in the 3D printing process. It will be damaged after being deformed by force. The disc spring (4) in the disc spring-like flexible structure (3) has a growth angle of Φ, and there is a gap of Δd1 between the two disc springs (4). The distance between the disc spring (4) and the upper plate (2) of the part is Δd2. Φ is any one of 35°, 40°, and 45°, Δd1 is any one of 0.3mm, 0.4mm, and 0.5mm, and Δd2 is 0.5mm.

2. The 3D printed load-bearing energy-absorbing device according to claim 1, characterized in that: When there are multiple disc spring-like flexible structures (3), the disc spring-like flexible structures (3) are arranged on the part base plate (1) and arranged periodically with a center distance of L.

3. The 3D printed load-bearing energy-absorbing device according to claim 2, characterized in that: The suspended areas between the disc spring-like flexible structures (3) are connected by a second support component. The second support component plays a supporting role during the 3D printing process and will be damaged after being deformed by force.

4. The 3D printed load-bearing energy-absorbing device according to claim 3, characterized in that: The second support component is a columnar support component or a tree-shaped support component.

5. A method for manufacturing a 3D-printed load-bearing energy-absorbing device according to any one of claims 1-4, characterized in that the steps include... include: Step S1: The 3D-printed energy-absorbing device is sintered and formed using 3D printing. Step S2: Strike the combined disc spring unit to destroy the first support component (5).

Images