A shock-absorbing landing gear with a woodpecker head bone structure and a preparation method thereof

Abstract

The application relates to the technical field of landing gears, in particular to a shock-absorbing landing gear imitating the head bone structure of a woodpecker and a preparation method, wherein the main body of the shock-absorbing landing gear is prepared from a TiAl alloy material, and the shock-absorbing landing gear comprises, from outside to inside, a strength layer, a buffer layer and a toughness layer; the strength layer imitates the hyoid layer of the head bone of a woodpecker; the buffer layer imitates the cancellous bone layer of the head bone of a woodpecker; and the toughness layer imitates the cerebrospinal fluid layer of the head bone of a woodpecker. The landing gear prepared by imitating the head bone structure of a woodpecker has excellent shock-absorbing and impact-resisting capacity; the landing gear is prepared by adopting a selective laser melting (SLM) technology, the number of connecting pieces in the landing gear is reduced, unnecessary assembly steps are saved, and assembly errors are reduced; the material and the part are integrally formed, and complicated preparation steps and machining processes are avoided.

Description

Technical Field

[0001] This invention relates to the field of landing gear technology, specifically to a shock-absorbing landing gear with a woodpecker skull-like structure and its manufacturing method. Background Technology

[0002] Landing gear is the primary load-bearing component for aircraft takeoff and landing. It is used for takeoff and landing rolls, airport taxiing, and to mitigate impact during landing and ground movement, making it a critical part of ensuring flight safety. Statistics show that landing gear-related accidents account for more than two-thirds of all aircraft structural accidents. With the rapid development of my country's aerospace industry, the requirements for landing gear vibration reduction are becoming increasingly stringent. Current vibration damping and isolation equipment is no longer sufficient to meet engineering needs and is detrimental to lightweight aircraft design.

[0003] Many organisms in nature possess natural shock-absorbing and impact-resistant structures, perfectly adapting to high-intensity, high-frequency impacts. The woodpecker is a prime example. Despite its daily high-frequency, high-speed pecking motions, the woodpecker suffers no brain damage due to its unique skull structure. The woodpecker's head has at least three levels of shock absorption: the hyoid bone layer, which encircles the skull and acts as a safety belt during the initial impact; the cancellous bone layer, with its sponge-like structure, porous and able to absorb a large amount of impact energy, mitigating the impact force; and the cerebrospinal fluid layer, which further disperses the impact force and reduces the transmission of shock waves. This ingenious skull structure allows the woodpecker to withstand impacts up to 100 times its own weight without suffering injury. Summary of the Invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes a shock-absorbing landing gear with a woodpecker skull structure and a method for its preparation.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A shock-absorbing landing gear with a woodpecker skull-like structure, wherein the main body of the shock-absorbing landing gear is made of TiAl alloy material, and the shock-absorbing landing gear comprises, from the outside to the inside, a strength layer, a buffer layer and a toughness layer;

[0007] The strength layer is modeled after the hyoid bone layer of a woodpecker's skull;

[0008] The buffer layer is modeled after the cancellous bone layer of a woodpecker's skull;

[0009] The tough layer is modeled after the cerebrospinal fluid layer of a woodpecker's skull.

[0010] Furthermore, the strength layer is made of a TiAl alloy containing Ti5Si3 ceramic particles, wherein the concentration of Ti5Si3 ceramic particles is 5 vol.% to 25 vol.%.

[0011] Furthermore, the toughening layer is made of a TiAl alloy containing Nb, wherein Nb

[0012] Concentrations range from 2 at.% to 28 at.%.

[0013] Furthermore, the buffer layer includes a support structure and a filling structure. The support structure is a regularly arranged micron-level mesh structure. The micron-level mesh structure is uniformly distributed in a tree-like manner and includes multiple levels of filamentous structures from the center to the periphery. The number of metal wires at each level increases in a centrally symmetrical gradient from the center to the periphery, and the diameter of the metal wires decreases in a gradient with the level.

[0014] Furthermore, the diameter of the metal wire at the center of the micron-scale mesh structure is 300μm to 550μm, and the diameter of the metal wire decreases by 5μm to 10μm at each level, with the diameter of the last level metal wire being no less than 50μm.

[0015] Furthermore, the material used to prepare the micron-scale network structure is a TiAl alloy containing Ti5Si3 ceramic particles, and the filling material between the micron-scale network structures is a TiAl alloy containing Nb.

[0016] Furthermore, the three-layer structure of the landing gear is printed using laser selective melting (SLM) technology.

[0017] Furthermore, the specific steps of the laser selective melting (SLM) technology are as follows:

[0018] S1. The target powder is prepared by gas atomization. TiAl alloy powder with Nb concentration of 5 at.% and TiAl alloy powder with Ti5Si3 concentration of 10 vol.% are prepared respectively. The raw material powder is taken according to the proportion, and after degreasing, cleaning and drying, it is heated and melted in an electric furnace under argon gas with a purity of not less than 99.99% according to the raw material ratio. After cooling and solidification, the target powder is obtained and dried for later use.

[0019] S2. Load TiAl alloy powder containing Ti5Si3 for printing strength layer and buffer layer support structure, and TiAl alloy powder containing Nb for printing toughness layer and buffer layer filling structure into the powder storage tank of the equipment. Set the material type, from beginning to end, TiAl alloy powder containing Ti5Si3 and alloy powder containing Nb, and set various process parameters for each layer material during molding.

[0020] S3. Save the established three-dimensional model of the shock-absorbing landing gear with three layers of gradient materials as an STL format, and discretize the solid model into layered slices with a certain thickness and order.

[0021] S4. Import the scan path into the computer system;

[0022] S5. Preheat the substrate to 120°C and fix it horizontally. Spread a layer of TiAl alloy powder containing Ti5Si3 evenly on the surface of the substrate. Inert gas is introduced into the protective cavity. The inert gas is argon gas with a purity of not less than 99.99%.

[0023] S6. During printing, the laser head moves along a predetermined path above the worktable, perpendicular to the worktable surface. Powder is output sequentially according to the order of the three materials described. After one layer is formed, the laser head rotates 90° clockwise, perpendicular to the scanning direction of the previous layer. This process is repeated, layer by layer, printing the strength layer, buffer layer, and toughness layer of the shock-absorbing support, creating a TiAl shock-absorbing structure that mimics the skull structure of a woodpecker.

[0024] Furthermore, the scanning laser power used in the three-layer gradient material is 1.0kW, the scanning rate is 9mm / s, and the powder feeding rate is 5.67g / min; the layer height is set to 50μm.

[0025] The beneficial effects of this invention are:

[0026] 1. The landing gear manufactured in this invention, modeled after the structure of a woodpecker's skull, has excellent shock absorption and impact resistance.

[0027] 2. This invention uses selective laser melting (SLM) technology to manufacture landing gear, which reduces the number of connecting parts inside the landing gear, eliminates unnecessary assembly steps, and reduces assembly errors; the material and parts are integrally formed, eliminating cumbersome preparation steps and processing technology. Attached Figure Description

[0028] Figure 1 This is a cross-sectional view of the three-layer landing gear structure in this invention. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1

[0031] The main steps of a method for manufacturing a shock-absorbing landing gear with a woodpecker skull-like structure are as follows:

[0032] Selective laser melting (SLM) technology is used to fabricate landing gear, enabling the production of parts with gradient materials by changing the type of powder during the forming process, without the need to stop and change the material powder midway.

[0033] The printing process mainly includes printing preparation, printing start, and printing end. Printing preparation includes powder preparation, substrate adjustment, file import, powder spreading, and gas washing. Powder preparation involves preparing TiAl alloy powder containing Nb and Ti5Si3, as well as pure TiAl alloy powder, through gas atomization. Substrate adjustment involves preheating and horizontally fixing the substrate, with the printing process taking place on the substrate using a lifting frame. The file import process involves preparing materials such as... Figure 1 The STL format of the shock-absorbing landing gear 3D model is imported into the printing equipment. The powder spreading is to evenly spread a layer of prepared metal powder on the substrate surface. The gas washing is to fill the forming chamber with protective gas. The printing start is performed after the printing preparation is completed. During the printing process, the laser beam is sprayed onto the substrate surface according to the outline of the printing model, solidifying the metal powder on the substrate surface. The printing is carried out layer by layer until the printing is completed. After the printing is completed, the substrate is removed, the excess powder is shaken off, and the printed shock-absorbing landing gear is obtained.

[0034] Step 1: Prepare target powder by gas atomization. Prepare TiAl alloy powder with Nb concentration of 5 at.% and TiAl alloy powder with Ti5Si3 concentration of 10 vol.%. Take the raw material powder according to the ratio, and after degreasing, cleaning and drying, heat and melt it in an electric furnace under argon protection with a purity of not less than 99.99% according to the raw material ratio. After cooling and solidification, the target powder is obtained and dried for later use.

[0035] Step 2: Load TiAl alloy powder containing Ti5Si3 for printing strength layer 1 and buffer layer support structure 4, and TiAl alloy powder containing Nb for printing toughness layer 3 and buffer layer filling structure 5 into the powder storage tank of the equipment. Set the material types, from beginning to end: TiAl alloy powder containing Ti5Si3, then alloy powder containing Nb. Set various process parameters for each layer during molding. The scanning laser power for the three gradient materials (strength layer 1, buffer layer 2, and strength layer 3) is 1.0kW, the scanning rate is 9mm / s, and the powder feed rate is 5.67g / min. The layer height is set to 50μm.

[0036] Step 3: Save the completed 3D model of the shock-absorbing landing gear with three layers of gradient material as shown in Figure 2 as an STL format, and discretize the solid model into layered slices with a certain thickness and order;

[0037] Step 4: Import the scan path into the computer system;

[0038] Step 5: Preheat the substrate to 120°C and fix it horizontally. Spread a layer of TiAl alloy powder containing Ti5Si3 evenly on the surface of the substrate. Inert gas is introduced into the protective cavity. The inert gas is argon gas with a purity of not less than 99.99%.

[0039] Step Six: Laser Additive Manufacturing of TiAl Shock-Absorbing Landing Gear with Woodpecker Skull-like Structure

[0040] During printing, the laser head moves along a predetermined path above the worktable, perpendicular to the worktable surface. It outputs powder sequentially according to the order of the three materials specified. After one layer is formed, the laser head rotates 90° clockwise, perpendicular to the scanning direction of the previous layer. This process is repeated, layer by layer, printing the strength layer, buffer layer, and toughness layer of the shock-absorbing support, creating a TiAl shock-absorbing structure that mimics the skull structure of a woodpecker.

[0041] After printing is complete, remove the formed shock-absorbing support part and turn off the additive manufacturing equipment.

[0042] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0043] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A shock-absorbing landing gear with a woodpecker skull-like structure, characterized in that, The main body of the shock-absorbing landing gear is made of TiAl alloy material, and the shock-absorbing landing gear includes a strength layer, a buffer layer and a toughness layer from the outside to the inside. The strength layer is modeled after the hyoid bone layer of a woodpecker's skull; The buffer layer is modeled after the cancellous bone layer of a woodpecker's skull; The tough layer is modeled after the cerebrospinal fluid layer of a woodpecker's skull; The strength layer is made of a TiAl alloy containing Ti5Si3 ceramic particles, wherein the concentration of Ti5Si3 ceramic particles is 5 vol.% to 25 vol.%. The toughening layer is made of a TiAl alloy containing Nb, wherein the Nb concentration is 2 at.% to 28 at.%; The buffer layer includes a support structure and a filling structure. The support structure is a regularly arranged micron-level mesh structure. The micron-level mesh structure is uniformly distributed in a tree-like manner and contains multiple levels of filamentous structures from the center to the periphery. The number of metal wires at each level increases in a centrally symmetrical gradient from the center to the periphery, and the diameter of the metal wires decreases in a gradient with the level.

2. The shock-absorbing landing gear with a woodpecker skull-like structure according to claim 1, characterized in that, The diameter of the metal wire at the center of the micron-scale mesh structure is 300μm to 550μm, and the diameter of the metal wire decreases by 5μm to 10μm at each level.

3. The shock-absorbing landing gear with a woodpecker skull structure according to claim 2, characterized in that, The micron-scale network structure is prepared from a TiAl alloy containing Ti5Si3 ceramic particles, and the filling material between the micron-scale network structures is a TiAl alloy containing Nb.

4. A method for manufacturing a shock-absorbing landing gear with a woodpecker skull-like structure as described in claim 3, characterized in that, The three-layer structure of the landing gear is printed using laser selective melting technology.

5. The preparation method according to claim 4, characterized in that, The specific steps of the laser selective melting technology are as follows: S1. The target powder is prepared by gas atomization. TiAl alloy powder with Nb concentration of 5 at.% and TiAl alloy powder with Ti5Si3 concentration of 10 vol.% are prepared respectively. The raw material powder is taken according to the proportion, and after degreasing, cleaning and drying, it is heated and melted in an electric furnace under argon gas with a purity of not less than 99.99% according to the raw material ratio. After cooling and solidification, the target powder is obtained and dried for later use. S2. Load TiAl alloy powder containing Ti5Si3 for printing strength layer and buffer layer support structure, and TiAl alloy powder containing Nb for printing toughness layer and buffer layer filling structure into the powder storage tank of the equipment. Set the material type, from beginning to end, TiAl alloy powder containing Ti5Si3 and alloy powder containing Nb, and set various process parameters for each layer material during molding. S3. Save the established three-dimensional model of the shock-absorbing landing gear with three layers of gradient materials as an STL format, and discretize the solid model into layered slices with a certain thickness and order. S4. Import the scan path into the computer system; S5. Preheat the substrate to 120°C and fix it horizontally. Spread a layer of TiAl alloy powder containing Ti5Si3 evenly on the surface of the substrate. Inert gas is introduced into the protective cavity. The inert gas is argon gas with a purity of not less than 99.99%. S6. During printing, the laser head moves along a predetermined path above the worktable and is perpendicular to the worktable surface. Powder is output sequentially according to the order of the three materials set. After one layer is formed, the laser head rotates 90° clockwise, perpendicular to the scanning direction of the previous layer. This process is repeated, layer by layer, to print the strength layer, buffer layer, and toughness layer of the shock-absorbing support, creating a TiAl shock-absorbing structure that resembles a woodpecker's skull.

6. The preparation method according to claim 5, characterized in that, The three-layer gradient material uses a scanning laser with a power of 1.0kW, a scanning rate of 9mm / s, and a powder feeding rate of 5.67g / min; the layer height is set to 50μm.

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