Method for cooperatively manufacturing bimetallic component based on SLM (selective laser melting) and FDM (frequency division multiplexing)

Abstract

The invention relates to a method for cooperatively manufacturing a bimetallic component based on SLM and FDM. The method comprises the following steps that (1) a three-dimensional model of a printed piece is established; (2) establishing a three-dimensional model of the inlaying mold; (3) printing a first metal and mosaic model; (4) cleaning powder and mounting an inlaid model; and (5) printing a second metal component. According to the method, powder pollution can be reduced, the use amount of printing materials is reduced, and the cost of SLM additive manufacturing of the bimetallic structure is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a method for collaboratively manufacturing a bimetallic component based on SLM and FDM. Background Art

[0002] Bimetallic structural materials are a new type of material obtained by metallurgically combining multiple materials with different properties through specific hybrid processing technology. It combines the excellent properties of two materials and improves the limitations of single material performance. It is currently widely used in aerospace, shipbuilding, automobile manufacturing and other fields. [1-3] . At present, bimetallic structural parts are mainly realized through traditional connection methods (welding, riveting, bonding). Among them, bonding is unstable for the connection between metal parts, the joint strength is insufficient, and it is easy to break at the joint. Traditional welding and riveting methods can often only handle relatively simple geometric figures, and it is difficult to manufacture heterogeneous metal components with complex composite structures. How to integrate multi-material systems with different performance advantages to directly manufacture heterogeneous material components with complex shapes and structures in response to the demand for high-performance components in important fields such as aviation, aerospace, and light water reactors is the main problem now faced.

[0003] Selective Laser Melting (SLM) is a major technical approach in the additive manufacturing of metal materials. This technology uses laser as the energy source and scans the metal powder bed layer by layer according to the path planned in the 3D CAD (Computer Aided Design) slice model. The scanned metal powder is melted and solidified to achieve the effect of metallurgical bonding, and finally the metal parts designed by the model are obtained. At present, although SLM technology has been maturely applied to the additive manufacturing of single materials, it has not been maturely applied in the additive manufacturing of multi-material metal structures. In many applications, such as the manufacture of certain aerospace engine components, conformal cooling molds, medical implants and functional gradient structures, it is necessary to use a combination of multiple materials to achieve their different purposes. [4] Therefore, it is necessary to design a selective laser melting device that can print multiple materials to meet the additive manufacturing needs of composite structural metal materials.

[0004] At present, the main working principle of SLM forming equipment is as follows: the forming cylinder is lowered below the working surface, and the drop height can be adjusted according to requirements, and then the powder spreading cylinder is raised to make the metal powder higher than the working surface; then the scraper moves horizontally from the powder cylinder to the forming cylinder along the working surface, and the powder is evenly spread to the surface of the forming cylinder; finally, according to the pre-set path, the laid metal powder is melted and cooled and solidified by laser scanning. If this equipment structure needs to add multiple metals, it needs to be replaced by powder, and when printing the second powder, the second powder needs to be filled to the height of the component that has been added before powder spreading printing can be performed, which greatly increases the demand for the second powder and will cause powder cross-contamination.

[0005] Therefore, existing research usually improves SLM forming equipment to achieve SLM manufacturing of multiple materials. Chinese patent CN106180711B discloses a selective laser melting powder spreading process for powder materials. The main function is to accurately spread powders of different material components at fixed points on the powder bed through multiple nozzles, and then through SLM manufacturing, continuous gradient changes of materials between different parts can be achieved. Powder is spread along the material ratio line, and mixed powders of different ratios can be obtained through the cooperation of various flow controllers. Chinese patent CN110576607B discloses an SLM additive manufacturing device with a functional gradient structure. The invention adopts a powder feeding device with a rotating function, which effectively reduces the volume of the equipment while realizing double-sided powder feeding; at the same time, it can realize the printing and powder feeding of the functional gradient structure; the powder spreading device reciprocates to spread the powder, and there is no empty stroke, which effectively improves the powder spreading efficiency; the two powder pressing devices realize double powder pressing, which effectively improves the density of the powder bed, and the forming quality of the parts can be well improved. However, the above methods can only realize laser additive manufacturing of multi-component mixed metal powders, and cannot prepare parts with heterogeneous metal composite structures. Chinese patent CN103978211B discloses a powder spreading and recovery device for selective laser melting of heterogeneous materials, including a powder spreading device that can move along a horizontal fixed guide rail and multiple powder spreading grooves; an adsorption cover that can cover the plane of the forming cylinder, which can adsorb the remaining powder after one material is solidified, and then lay another material for solidification. However, in this design, an overly large adsorption cover will interfere with the laser scanning device, and the adsorption effect is not good. In addition, the metal powder remaining on the forming base surface is easy to contaminate other types of metal powder. Chinese patent CN115815631A discloses a composite structure metal material selective laser melting additive manufacturing device, which divides the metal powder container into a powder spreading cylinder and a powder feeding cylinder, and uses a powder feeding gun to control the powder feeding of heterogeneous metal materials by controlling the gas flow rate through an electromagnetic valve. For heterogeneous metals, powder spreading and coaxial powder feeding are used to perform additive manufacturing of composite structure metal parts. However, this design is too complicated, the control accuracy of the equipment is high, and the cost of equipment modification is high. Summary of the invention

[0006] The purpose of the present invention is to provide a method for collaboratively manufacturing bimetallic components based on SLM and fused deposition modeling (FDM), which can reduce powder pollution, reduce the amount of printing materials, and save the cost of SLM additive manufacturing of bimetallic structures.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: a method for collaboratively manufacturing a bimetallic component based on SLM and FDM, comprising the following steps: (1) Establish a three-dimensional model of the printed part; (2) Establishing a three-dimensional model of the inlay mold; (3) Printing the first metal and inlay models; (4) Cleaning powder and installing mosaic models; (5) Printing the second metal component.

[0008] Furthermore, in step (1), the bimetallic component to be processed is subjected to computer three-dimensional modeling, the model is sliced ​​and layered, and the components of the first metal and the second metal are clearly defined, and then the slice data is imported into the SLM device to form a processing trajectory.

[0009] Furthermore, in step (2), the mosaic model is subjected to computer 3D modeling. First, a model is established according to the height of the printed part and the size of the forming cylinder. Then, the model is subjected to entity cutting processing according to the shape of the printed part and the position of the printed part in the forming cylinder. Then, the model is subjected to slicing and layering and support generation processing. The slicing data is then imported into the FDM device to form a processing trajectory.

[0010] Furthermore, in step (3), a plate having the same composition as that of the first powder to be printed is selected as a substrate, the first metal powder is evenly laid layer by layer on the surface of the metal substrate, laser additive manufacturing is performed under the protection of an inert gas to form a first single metal component, and a mosaic model is printed on an FDM device at the same time.

[0011] Furthermore, in step (4), after printing the first metal, the forming cylinder, powder cylinder and powder collection bottle in the SLM equipment are cleaned and the powder is recovered, and then the printed mosaic model is matched with the shape of the first metal forming part and embedded in the base plate of the forming cylinder.

[0012] Furthermore, in step (5), a second powder is introduced into the powder cylinder, the second powder is evenly spread on the surface of the printed first metal and the inlay model, and laser additive manufacturing is performed on the formed print under the protection of an inert gas to obtain a bimetallic component.

[0013] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention fully combines and utilizes the existing SLM metal additive manufacturing equipment and FDM polymer additive manufacturing method to realize the forming and manufacturing of bimetallic components. When different metal components of the component are formed by SLM, the corresponding mosaic model is simultaneously manufactured by FDM, which effectively combines the advantages of SLM and FDM additive manufacturing. The direct forming and manufacturing of bimetallic structural parts can be realized without redesigning and developing the existing SLM equipment.

[0014] (2) The method of forming different metal component parts by FDM and embedding molds proposed in the present invention has flexible design and low cost. It can effectively solve the problem of powder contamination caused by the second metal during printing when forming multi-metal components by SLM, improve the utilization rate and recycling value of powder, and has the advantages of saving materials and increasing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a flow chart of a method implementation of an embodiment of the present invention; Figure 2 is a schematic diagram of a bimetallic component model in an embodiment of the present invention; Figure 3 Schematic diagram of an FDM additive manufacturing bimetallic component inlay model according to an embodiment of the present invention; Figure 4 is a schematic diagram of the first metal part of the additive in an embodiment of the present invention; Figure 5 is a schematic diagram of a process of embedding a mosaic model into a substrate in an embodiment of the present invention; Figure 6 is a schematic diagram of the metal of the second part of the additive after the inlay model is embedded in the embodiment of the present invention; Figure 7 Schematic diagram of a bimetallic component printed in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0018] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0019] like Figure 1 As shown, this embodiment provides a method for collaboratively manufacturing bimetallic components based on SLM and FDM, and the specific implementation steps are as follows.

[0020] (1) Create a 3D model of the printed part The bimetallic component to be processed is modeled in three dimensions by computer, the model is sliced ​​and layered, and the components of the first metal and the second metal are clearly defined. The slice data is then imported into the SLM equipment to form a processing trajectory.

[0021] (2) Establish a 3D model of the inlay mold The mosaic model is 3D modeled by computer. First, a model is established according to the height of the printed part and the size of the forming cylinder. Then, the model is cut out according to the shape of the printed part and the position of the printed part in the forming cylinder. Then, the model is sliced ​​and layered, and support processing is generated. The slice data is imported into the FDM equipment to form a processing trajectory.

[0022] (3) Printing the first metal and inlay model A plate with the same composition as the first powder to be printed is selected as the substrate, and the first metal powder is evenly laid layer by layer on the surface of the metal substrate. Laser additive manufacturing is performed under the protection of inert gas to form the first single metal component, and the mosaic model is printed on the FDM equipment at the same time.

[0023] (4) Cleaning powder and installing mosaic models After printing the first metal, the forming cylinder, powder cylinder and powder collection bottle in the SLM equipment are cleaned and the powder is recovered. Then the printed mosaic model is matched to the shape of the first metal forming part and embedded in the base plate of the forming cylinder.

[0024] (5) Printing the second metal component The second powder is introduced into the powder cylinder, and the second powder is evenly spread on the surface of the first metal and the inlaid model after printing. Laser additive manufacturing is performed on the formed print part under the protection of inert gas to obtain a bimetallic component.

[0025] In this embodiment, the printing model established is as follows Figure 2As shown, it includes a crown part 1 printed from 2205 duplex stainless steel powder with a powder size of 15-53 μm, and a tooth part 2 printed from IN718 nickel-based high-temperature alloy powder with a powder size of 15-53 μm using the printing setting of 2205 duplex stainless steel.

[0026] In this embodiment, according to the shape of the printed part, the position of the printed part in the forming cylinder, the printing height and the size of the forming cylinder, the mosaic model is three-dimensionally modeled by computer, the model is sliced ​​and layered, and the slice data is imported into the FDM equipment, and then the FDM equipment is used for additive manufacturing, as shown in the schematic diagram. Figure 3 As shown, the mosaic model is 3.

[0027] In this embodiment, 2205DSS duplex stainless steel powder is used to print the first metal component part. Figure 4 As shown, it includes a substrate 4, a first metal additive component 5 and a first powder 6. 2205 duplex stainless steel is selected as the substrate, and 2205 duplex stainless steel metal powder is evenly laid layer by layer on the surface of the metal substrate according to the processing trajectory. The thickness of each layer of stainless steel metal powder is 30 μm, the laser power is 340 W, and the scanning speed is 50 mm / s.

[0028] In this embodiment, after the first metal is printed and the powder is cleaned, the position of the mosaic model is adjusted according to the shape of the printed first part of the metal and embedded in the forming cylinder substrate. The process is as follows: Figure 5 It includes an inlay model 3, a substrate 4 and a first metal component 5.

[0029] In this embodiment, after the model is embedded, IN718 nickel-based high-temperature alloy powder is used to print the second metal component part and the powder spreading process is as follows: Figure 6 As shown, it includes a substrate 4, a first metal component 5, a second metal component 7, and a second powder 8. IN718 nickel-based high-temperature alloy powder is evenly laid on the surface of the printed first metal and the inlay model, and laser additive manufacturing is performed on the formed print under the protection of inert gas. The thickness of each layer of stainless steel metal powder is set to 30μm, the laser power is 250W, and the scanning speed is 1m / s to obtain a bimetallic component. The printed bimetallic component is as shown in FIG. Figure 7 shown.

[0030] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A method for collaboratively manufacturing bimetallic components based on SLM and FDM, characterized in that: The following steps are involved: (1) Establish a three-dimensional model of the printed part; (2) Establishing a three-dimensional model of the inlay mold; (3) Printing the first metal and inlay models; (4) Cleaning powder and installing mosaic models; (5) Printing the second metal component.

2. The method for collaboratively manufacturing a bimetallic component based on SLM and FDM according to claim 1, characterized in that: In step (1), the bimetallic component to be processed is subjected to computer three-dimensional modeling, the model is sliced ​​and layered, and the components of the first metal and the second metal are clearly defined. The slice data is then imported into the SLM device to form a processing trajectory.

3. The method for collaboratively manufacturing a bimetallic component based on SLM and FDM according to claim 1, characterized in that: In step (2), the mosaic model is subjected to computer 3D modeling. First, a model is established according to the height of the printed part and the size of the forming cylinder. Then, the model is subjected to entity cutting processing according to the shape of the printed part and the position of the printed part in the forming cylinder. Then, the model is subjected to slicing and layering and support generation processing. The slicing data is then imported into the FDM equipment to form a processing trajectory.

4. The method for collaboratively manufacturing a bimetallic component based on SLM and FDM according to claim 1, characterized in that: In step (3), a plate having the same composition as that of the first powder to be printed is selected as a substrate, the first metal powder is evenly laid layer by layer on the surface of the metal substrate, laser additive manufacturing is performed under the protection of an inert gas to form a first single metal component, and a mosaic model is printed on an FDM device at the same time.

5. The method for collaboratively manufacturing a bimetallic component based on SLM and FDM according to claim 1, characterized in that: In step (4), after printing the first metal, the forming cylinder, powder cylinder and powder collection bottle in the SLM equipment are cleaned and the powder is recovered, and then the printed mosaic model is matched with the shape of the first metal forming part and embedded in the base plate of the forming cylinder.

6. The method for collaboratively manufacturing a bimetallic component based on SLM and FDM according to claim 1, characterized in that: In step (5), the second powder is introduced into the powder cylinder, and the second powder is evenly spread on the surface of the first metal and the inlaid model after printing. Laser additive manufacturing is performed on the formed print under the protection of inert gas to obtain a bimetallic component.

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