WO2024014763A1

WO2024014763A1 - Method for forming multi-material structure

Info

Publication number: WO2024014763A1
Application number: PCT/KR2023/009344
Authority: WO
Inventors: 김대중
Original assignee: 주식회사 에이엠솔루션즈
Priority date: 2022-07-13
Filing date: 2023-07-03
Publication date: 2024-01-18
Also published as: KR20240009089A

Abstract

The present invention relates to a method for forming a multi-material structure having improved durability through metal additive manufacturing, the method comprising: a step for supplying a first material onto a surface through a nozzle that moves along a tool path, and melting the first material to laminate a first layer; and a step for supplying a second material onto another surface through a nozzle that moves along a tool path, and melting the second material to laminate a second layer, wherein the first layer is formed as a metal layer and the second layer is formed as a metal oxide layer.

Description

Method for forming multi-material structures

The present invention relates to a method of forming a multi-material structure, and more specifically, the step of supplying and melting a first material through a nozzle moving along a tool path on one surface to form a first layer, and depositing a first layer on another surface. supplying and melting a second material through a nozzle moving along the tool path to deposit a second layer, wherein the first layer is formed of a metal layer and the second layer is formed of a metal oxide layer. However, the step of laminating the first layer includes a first material supply step of supplying the first material to the surface, and a process gas supply step of supplying a process gas to the area where the first material is supplied simultaneously with the first material supply step. It includes a supply step, wherein the process gas includes an inert gas, and the step of laminating the second layer includes a second material supply step of supplying a second material on the surface, and a second material supply step simultaneously with the second material supply step. It includes a first gas supply step of supplying a first gas to the area where the material is supplied, and the first gas contains oxygen, thereby obtaining a structure having a layer with a high oxygen fraction on the outer surface, through which a high diameter It relates to a method of forming a multi-material structure that can produce a structure with characteristics such as durability, wear resistance, corrosion resistance, etc.

A 3D printer reduces design errors by manufacturing a shape created using 3D computer-aided design (CAD, etc.) and makes it easier to manufacture objects than casting. Among these, metal lamination as shown in Figure 1. Unlike 3D printing technology that uses existing polymer materials, the processing technology is a technology that stacks three-dimensional shapes using metal powder and metal wire. Conventional metal additive manufacturing was carried out by creating a layer-based toolpath in CAM S/W and applying process variables such as input materials and heat source settings, and the technology was developed by applying different physical properties and process variables for each layer. did.

Additive manufacturing technology is a technology that creates layers of input materials by simultaneously injecting heat sources, materials, and process gases at specific points on the base material. The process gas in the above process is an inert gas such as argon or nitrogen gas, or an equivalent gas, which suppresses the formation of oxides on the surface of the material and thereby ensures stacking stability. Additive manufacturing technology with these characteristics has a limitation in that it cannot use materials with a high oxygen content, and to overcome this limitation, methods that apply additional processes such as pre-heating and post-heating to control the amount of heat input and cooling rate are used. Although developed, a fundamental solution has not been found.

Additionally, when it is necessary to protect products formed through a lamination process, such as implants or mechanical parts, from the external environment, the inside can be protected by forming an oxide film on the outermost surface. There is a problem that forming oxides on the surface of these products requires additional processes and takes a long time.

(Patent Document 1) Korean Patent Publication No. 10-2331728 (2021.11.23.)

The present invention is intended to solve the problems of the prior art described above,

The object of the present invention is to deposit a first layer by supplying and melting a first material through a nozzle moving along a tool path on one surface, and forming a first layer through a nozzle moving along a tool path on another surface. It includes the step of supplying and melting two materials to laminate a second layer, wherein the first layer is formed of a metal layer and the second layer is formed of a metal oxide layer, so that durability is improved through metal additive manufacturing. A method of forming a material structure is provided.

The purpose of the present invention is that the step of laminating the second layer includes supplying a second material to the surface, supplying a first gas to the area where the second material is supplied at the same time as the step of supplying the second material. A method of forming a multi-material structure is provided, comprising a step of supplying a first gas, wherein the first gas contains oxygen, and a metal oxide layer can be formed on the outside of the product during the metal lamination process without any additional process. .

The purpose of the present invention is that the step of laminating the first layer includes supplying a first material to the surface, supplying a process gas to the area where the first material is supplied at the same time as the first material supply step. It includes a process gas supply step, wherein the process gas includes an inert gas, thereby providing a method of forming a multi-material structure that prevents oxide generation during the stacking process of the metal layer.

The object of the present invention is to convert the supplied process gas into the first gas, or to easily convert the lamination of the metal layer and the metal oxide layer by further comprising a gas conversion step of converting the supplied first gas into the process gas. To provide a method of forming a multi-material structure.

The object of the present invention is that the first material and the second material are metal powders or alloy powders containing the same metal element, and the metal elements are titanium (Ti), zirconium (Zr), aluminum (Al), and copper (Cu). ), chromium (Cr), and provides a method of forming a multi-material structure that is easy to bond by placing a metal layer between the substrate and the outermost ceramic layer.

The purpose of the present invention is to stack the first layer by supplying and melting the first material on the substrate, and to laminate the second layer by supplying and melting the first material on the substrate. A method of forming a multi-material structure having a structure of a base-metal layer-metal oxide layer is provided by supplying a first gas containing oxygen and stacking a second layer of metal oxide.

The purpose of the present invention is to provide a method of forming a multi-material structure in which the tool path is formed on a curved surface or two or more planes that intersect at a predetermined angle, enabling three-dimensional metal stacking.

The purpose of the present invention is to quickly form the structure of the base-metal layer-metal oxide layer by allowing the steps of stacking the first layer and the step of stacking the second layer to be performed alternately while the nozzle moves along the tool path. The aim is to provide a method of forming an economical multi-material structure by stacking.

The object of the present invention further includes a mapping step of mapping a first layer area and a second layer area to a tool path, wherein a step of stacking the first layer is performed in the first layer area on the tool path, and a second layer area is stacked. In the layer area, the step of laminating the second layer is performed, and the gas conversion step converts the gas supplied when the nozzle moving along the tool path enters the first layer area into the second layer area from the process gas to the first layer. To provide a method of forming a multi-material structure that converts the gas supplied when the nozzle enters from the second layer area to the first layer area and converts the first gas into a process gas.

In order to achieve the above-described object, the present invention is implemented by an embodiment having the following configuration.

According to one embodiment of the present invention, the present invention includes the steps of supplying and melting a first material through a nozzle moving along a tool path on one surface to deposit a first layer, and forming a tool path on another surface. A step of supplying and melting a second material through a moving nozzle to deposit a second layer, wherein the first layer is formed of a metal layer and the second layer is formed of a metal oxide layer. do.

According to one embodiment of the present invention, the step of laminating the second layer includes supplying a second material to the surface, and simultaneously supplying the second material to the area where the second material is supplied. It includes a first gas supply step of supplying one gas, and the first gas includes oxygen.

According to one embodiment of the present invention, the step of laminating the first layer includes a first material supply step of supplying the first material to the surface, and a process to the area where the first material is supplied simultaneously with the first material supply step. A process gas supply step of supplying gas, wherein the process gas includes an inert gas.

According to one embodiment of the present invention, the present invention is characterized by further comprising a gas conversion step of converting the supplied process gas into the first gas, or converting the supplied first gas into the process gas.

According to one embodiment of the present invention, the first material and the second material are metal powders or alloy powders containing the same metal element, and the metal elements are titanium (Ti), zirconium (Zr), aluminum (Al), It is characterized as being one of copper (Cu) and chromium (Cr).

According to one embodiment of the present invention, the step of laminating the first layer is to supply and melt the first material on the substrate to laminate the first layer, and the step of laminating the second layer is to layer the first material on the first layer. It is characterized by supplying a second material and supplying a first gas containing oxygen to stack a second layer of metal oxide.

According to one embodiment of the present invention, the tool path is formed on a curved surface or two or more planes that intersect at a predetermined angle.

According to one embodiment of the present invention, the nozzle moves along the tool path, and the step of laminating the first layer and the step of laminating the second layer are performed alternately.

According to one embodiment of the present invention, it further includes a mapping step of mapping the first layer area and the second layer area to the tool path, and a step of stacking the first layer is performed in the first layer area on the tool path, , Characterized in that the step of laminating the second layer is performed in the second layer region.

According to one embodiment of the present invention, the gas conversion step converts the gas supplied when the nozzle moving along the tool path enters the first layer area into the second layer area from the process gas to the first gas, When the nozzle enters the first layer area from the second layer area, the supplied gas is converted from the first gas to the process gas.

The present invention has the following effects through the above-described configuration.

The present invention provides the steps of supplying and melting a first material through a nozzle moving along a tool path on one surface to deposit a first layer, and applying a second material through a nozzle moving along a tool path on another surface. Comprising the step of supplying and melting a second layer, wherein the first layer is formed of a metal layer and the second layer is formed of a metal oxide layer, thereby providing a multi-material structure with improved durability through metal additive manufacturing. It has the effect of providing a method of forming .

In the present invention, the step of laminating the second layer includes supplying a second material to the surface, supplying a first gas to the area where the second material is supplied simultaneously with the step of supplying the second material. It includes a first gas supply step, wherein the first gas contains oxygen, enabling the formation of a metal oxide layer on the outside of the product during the metal stacking process without any additional process.

In the present invention, the step of laminating the first layer includes a first material supply step of supplying the first material to the surface, and a process of supplying a process gas to the area where the first material is supplied simultaneously with the first material supply step. It includes a gas supply step, and the process gas contains an inert gas and has the effect of preventing oxide generation during the stacking process of the metal layer.

The present invention further includes a gas conversion step of converting the supplied process gas into the first gas, or converting the supplied first gas into the process gas, thereby providing the effect of easily converting the lamination of the metal layer and the metal oxide layer. give.

In the present invention, the first material and the second material are metal powders or alloy powders containing the same metal element, and the metal elements are titanium (Ti), zirconium (Zr), aluminum (Al), copper (Cu), It is made of chromium (Cr) and has the effect of facilitating bonding by placing a metal layer between the substrate and the outermost ceramic layer.

In the present invention, in the step of laminating the first layer, a first material is supplied and melted on a substrate to laminate the first layer, and in the step of laminating the second layer, a second material is supplied on the first layer. There is an effect of providing a method of forming a multi-material structure having a structure of a base-metal layer-metal oxide layer by supplying a first gas containing oxygen and stacking a second layer of metal oxide.

In the present invention, the tool path is formed on a curved surface or two or more planes that intersect at a predetermined angle, enabling three-dimensional metal stacking.

In the present invention, while the nozzle moves along the tool path, the steps of stacking the first layer and the steps of stacking the second layer are performed alternately, thereby quickly stacking the structure of the base-metal layer-metal oxide layer. It is economical.

The present invention further includes a mapping step of mapping a first layer area and a second layer area to a tool path, where a step of stacking the first layer is performed in the first layer area on the tool path, and the second layer area is In the step of laminating the second layer, the gas conversion step converts the gas supplied when the nozzle moving along the tool path enters the first layer area into the second layer area from the process gas to the first gas. It has the effect of providing a method of forming a multi-material structure that converts the gas supplied when the nozzle enters from the second layer area to the first layer area from the first gas to the process gas.

Figure 1 is a conceptual diagram of additive manufacturing according to the prior art.

Figure 2 is a flow chart of a method of forming a multi-material structure according to an embodiment of the present invention.

3 and 4 are cross-sections of a multi-material structure that is a product formed by the method (S) of forming a multi-material structure according to the present invention.

Figure 5 is a diagram showing a 3D printing device for carrying out the present invention.

Figure 6 is a diagram illustrating generating a toolpath according to an embodiment of the present invention.

Figure 7 is a diagram showing a toolpath being formed in 3D image data.

Figure 8 is a cross-section taken along line A-A' of Figure 7 according to an embodiment of the present invention.

Figure 9 is a cross-section taken along line A-A' of Figure 7 according to another embodiment of the present invention.

Figure 10 is a flow chart of the first layer stacking step (S30) and the second layer stacking step (S50) in one embodiment of the present invention.

Hereinafter, the 3D printer nozzle and 3D printer according to the present invention will be described in detail with reference to the attached drawings. Additionally, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the gist of the present invention will be omitted. It should be noted that like elements in the drawings are represented by like symbols wherever possible. Additionally, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the gist of the present invention are omitted. Unless otherwise specified, all terms in this specification have the same general meaning as understood by a person skilled in the art to which the present invention pertains, and if there is a conflict with the meaning of the terms used in this specification, this specification Follow the definitions used in the specification. Throughout the specification, when a part "includes" a certain component, this does not mean excluding other components unless specifically stated to the contrary, but also means that other components may also be included. Terms such as “~unit” described mean a unit that processes at least one function or operation. In addition, when certain components are said to be "connected," this is not limited to the components being directly contacted and fastened to each other, but also includes being connected through other components, and even if not connected, a certain amount of force or energy can be transmitted. It may mean that it is arranged so that Terms such as "1st~" and "2nd~" may be used to indicate the same or substantially the same configuration in a different order, and may be used to indicate the same or substantially the same configuration as the configuration without "1st", "2nd", etc. It can be interpreted as a composition. Hereinafter, the present invention will be described in detail by explaining preferred embodiments of the present invention with reference to the accompanying drawings.

Referring to Figure 2, the method (S) of forming a multi-material structure according to the present invention receives a three-dimensional image of the product formed through 3D printing or cladding, generates a tool path, which is the movement path of the nozzle, and creates a three-dimensional image. After mapping the metal layer area and metal oxide layer area of the product defined or determined according to the data to the tool path, the first material and process gas are supplied to the surface and heated to deposit the first layer, and the first layer containing oxygen is deposited. By supplying gas and a second material to the surface and heating them to deposit a second layer, a structure with a layer with a high oxygen content can be obtained on the outer surface, thereby creating a structure with characteristics such as high hardness, wear resistance, and corrosion resistance. It has features that can be manufactured. In the method (S) of forming the multi-material structure, metal or alloy powder is supplied as a material, an inert or inert gas containing argon and nitrogen is used as a process gas, and a gas containing oxygen is preferably used as the first gas. do. However, in the present invention, to the extent that can be understood by those skilled in the art, the material can be replaced with wire, filament, etc., and depending on the material, a suitable process gas with low activity of the material can be used, and a metal oxide layer or ceramic layer on the outer surface can be used. A gas other than oxygen may be replaced as the first gas to form a layer.

First, the multi-material structure, which is a product formed by the method (S) of forming a multi-material structure according to the present invention, will be described with reference to FIGS. 3 and 4. The product may include a substrate 10, a first layer 20, and a second layer 30. Here, the substrate 10 may be a metal, but may also be a non-metallic material such as ceramic or plastic. As shown in FIG. 3 , the first layer 20 may be laminated on one surface of the substrate 10 . The first material 21 is supplied to the substrate with the heat source 25 and melts on the surface to form a molten pool. As it cools and hardens, the first layer 20 is formed on the surface of the substrate 10. . The first material 21 may be a metal powder or an alloy powder, and the heat source 25 is preferably a laser. In this process, inert or inert gas is introduced as the process gas 23 to suppress oxide formation and improve stackability. It is desirable to use a gas that has low reactivity or does not react with the first material, such as argon (Ar) or nitrogen (N ₂ ), as the process gas.

Next, the second layer 30 may be laminated on the first layer 20. The second material 31 is supplied on the first layer with the heat source 35 to form a molten pool on the surface, and as it cools and hardens, the second layer 30 can be formed by stacking. The second material 31 may be a metal powder or an alloy powder, and the heat source 35 is preferably a laser. In this process, the first gas 33 containing oxygen is supplied so that the second layer 30 can be formed as a metal oxide layer. Accordingly, the first layer 20 may be formed of a metal layer, and the second layer may be formed of a metal oxide layer.

In a preferred embodiment of the present invention, the first material 21 and the second material 31 may be metal powders or alloy powders containing the same metal element. Additionally, the first material 21 and the second material 31 may be substantially the same metal powder or alloy powder. In one embodiment, a first layer 20 of zirconium (Zr) may be formed on a substrate 10 made of titanium (Ti), and a second layer 30 of zirconia may be formed on the first layer. . That is, the second layer 20, which is an oxide layer of the same metal, may be formed on the first layer 20, which is a metal layer. The product according to the present invention has a structure of base material - metal layer - metal oxide layer, so that a product with increased durability can be formed through cladding. In another embodiment of the present invention, the first layer 20 may be omitted and the second layer 30 may be laminated on the substrate 10. In this case, the substrate 10 may be substantially the same metal layer as the first layer 20. That is, by supplying oxygen together with zirconium powder on the zirconium substrate 10, the second layer 30 of zirconia can be formed to have a structure of a metal substrate and a metal oxide layer.

In addition, in FIGS. 3 and 4, the substrate 10 is shown to have the shape of a flat plate, but in one embodiment of the present invention, the substrate 10 has a curved and irregular surface, and the first layer 20 and the second layer 20 have a curved surface. Two layers 30 may be laminated on the substrate. In particular, the base material 10 may be an implant screw made of titanium or titanium alloy. In this case, the first layer 20 and the second layer 30 are not laminated in the shape of a flat surface, but are a base material with a curved surface as described later. It can be stacked to surround (10). Furthermore, as will be described later, the first layer 20 may be laminated on the surface of the first or second layer rather than the substrate 10, and the second layer 30 may be laminated on the surface of the first layer 20 instead of the first layer 20. It may also be laminated on the surface of the substrate or the second layer. Furthermore, as described above, the first layer 20 may be omitted and the second layer 30 may be laminated on the metal substrate 10.

Next, the main configuration of the 3D printing device for carrying out the present invention will be described with reference to FIG. 5. The 3D printing device includes a 3D printer 60 and a controller 50.

The controller 50 is configured to manage and control the overall operation of the 3D printer 60, and forms a tool path for producing a product corresponding to the input 3D modeling data and 3D image data through a layering process, Through numerical analysis, the material can be specified or the product can be divided into a metal layer, metal oxide layer, or ceramic layer according to the desired physical properties of the product, and the supply amount of materials and gas provided through the 3D printer can be controlled. To this end, the controller 10 may be driven by at least one processor and may include a data conversion unit 51, a tool path generation unit 53, a numerical analysis unit 54, and a supply control unit 55. there is.

The data conversion unit 51 may be provided to convert the input 3D image data into stereoscopic data in a format such as STL. The converted three-dimensional data includes information about the vertices of each mesh and information about the surface formed by the mesh.

The tool path generator 53 is configured to render a 3D model from three-dimensional modeling data and generate a tool path, which is a movement path of a nozzle during additive manufacturing. Referring to FIG. 4, the toolpath generator 53 slices the rendered 3D modeling data and 3D image data (D) into a plurality of faces and creates a slice in the area where each face intersects the 3D image data (D). A tool path, which is the moving path of the nozzle, is created by drawing a plurality of line segments according to a predetermined algorithm. In FIG. 6, a plurality of slicing surfaces are shown as flat surfaces, but as will be described later, the surface slicing the 3D image data (D) may be a curved surface or two or more flat surfaces, and the tool path may be a curved surface or a surface that intersects at a predetermined angle. It can be formed on two or more planes. As shown in FIG. 4, in one embodiment of the present invention, the tool path can fill the intersecting area in a zigzag direction, and filling the intersecting area with other shapes, including concentric circle shapes, is not excluded from the scope of rights. . The size and porosity of the toolpath can be adjusted by adjusting the spacing of line segments filled along the intersecting area.

Referring again to FIG. 5, the numerical analysis unit 54 is equipped to perform numerical analysis according to an objective function, and determines the material of the product through numerical analysis or determines the thickness of the metal layer, metal oxide layer, or ceramic layer of the product. The thickness can be determined. The numerical analysis unit 54 can specify an objective function according to the optimization goal of the physical properties of the shape of the 3D image data, and perform numerical analysis according to the determined objective function to determine the material for forming the product. The determined material can be laminated on the surface of the substrate in a cladding manner. In a preferred embodiment, the material to be determined (including the first material and the second material) may be a metal powder. Here, the metal includes an alloy, and metal powder or alloy powder may be supplied as the first material or the second material. In particular, it is a material that increases durability when it reacts with oxygen to form a metal oxide layer, such as titanium (Ti), zirconium (Zr), aluminum (Al), copper (Cu), chromium (Cr), or alloys thereof. It can be determined by the supplied materials. In the case of titanium and zirconium alloys, free composition is possible within a range that satisfactorily forms a metal oxide layer such as titanium oxide and zirconia.

The supply control unit 55 is configured to control the type, amount, speed, etc. of the material supplied through the nozzle in the 3D printer 60, and controls the supply speed and amount of the material through the powder supply command from the supply control unit 55. This is delivered in real time. The supply control unit 55 can control the supply of gas including the process gas and the first gas along with the supply of the material containing the metal element. In particular, when the irradiation area changes depending on the beam size of the laser that heats the material or the thickness of the product required in a certain area on the tool path changes, the amount of process gas and/or first gas input can be adjusted and changed to ensure a smooth lamination process. can be performed.

When explaining the 3D printer 60 for practicing the present invention with reference to FIG. 5, the 3D printer forms a product through additive manufacturing, preferably by spraying metal powder through a nozzle and then using a heating means such as a laser. Additive manufacturing can be performed by welding it on the surface. The 3D printer 60 can supply and mix multiple types of materials and then spray them through a nozzle, and can supply process gas and first gas, which are different gases supplied for the lamination process, through a blower. The 3D printer may include a material supply unit 61, a nozzle 62, a process gas supply unit 63, a first gas supply unit 64, a blower 65, a heating unit 66, and a jig 67. .

The material supply unit 61 is a part that stores and supplies powder to be sprayed for additive manufacturing, and may be provided in plural numbers depending on the type of material. In another embodiment of the present invention, wire, filament, etc. are supplied rather than metal powder. It may be equipped to do so. Materials may be stored in a container having a predetermined volume of the material supply unit 61, and materials may be supplied to the nozzle 62. Materials as different metal or alloy powders may be present in the plurality of

containers

61a and 61b. It can be saved. The material supply unit 61 may mix and supply different materials. The material supply unit 61 can control the amount and/or speed of the material being discharged by adjusting the degree of opening and closing of the container and the rotation speed of the motor, and can adjust the amount and/or speed of the material by adjusting the vibration frequency when the material is discharged. You can also adjust .

The nozzle 62 is coupled to one side of the 3D printer and is provided to discharge or spray the supplied material onto the surface. The nozzle 62 can be controlled to move along the tool path described above. The nozzle 62 can be controlled to move back and forth, left and right, and move up and down to perform xyz axis movement, and its rotation may be controlled to change the discharge angle of the material toward the product held in the jig 67.

The process gas supply unit 63 is configured to supply an inert or inert gas to the area where the first material is supplied to prevent oxide generation when stacking the first layer 20, such as argon (Ar), nitrogen (N ₂ ) Gases such as can be stored and supplied.

The first gas supply unit 64 is configured to supply a first gas containing oxygen to the area where the second material is supplied to form a metal oxide layer when stacking the second layer 30. Stores and supplies gas.

The blower 65 supplies the process gas or first gas delivered from the process gas supply unit 63 or the first gas supply unit 64 to the area where the first material is supplied.

The heating unit 66 is provided at one end of the nozzle 62 to heat the material sprayed onto the surface to melt it. The heating unit 66 can heat the material by irradiating a laser, and the laser can be irradiated in a pulse manner depending on the stacking method. Heating portion 66 may be of other configurations suitable for melting material on the surface.

The jig 67 is configured to hold a product or a substrate and, together with a nozzle that discharges material, can tilt or rotate the held product or substrate to stack products in a three-dimensional shape.

Referring again to FIG. 2 and explaining the method (S) of forming a multi-material structure according to the present invention, the method (S) of forming a multi-material structure includes a tool path generation step (S10), a mapping step (S20), and a first It may include a layer stacking step (S30), a gas conversion step (S40), and a second layer stacking step (S50).

The tool path generation step (S10) is a process of receiving 3D image data including 3D modeling, slicing the 3D image data into a plurality of slices, and determining the movement path of the nozzle. The tool path generator 13 It can be performed by rendering the input 3D image data as a 3D object and then performing slicing on multiple surfaces. In the tool path generation step (S10), a tool path, which is a movement path of the nozzle, can be generated by drawing a plurality of line segments according to a predetermined algorithm in the area where the 3D image data (P) and each plane intersect. At this time, the toolpath may be formed on a curved surface or two or more planes that intersect at a predetermined angle, as shown in FIG. 7, or may be formed on one plane. The toolpath (T) can be stored as an array with 3D coordinate values and data necessary for the lamination process.

When the toolpath is formed on a curved surface or two or more planes that intersect at a predetermined angle, three-dimensional image data is sliced with a defined curved surface or two or more planes that intersect at a predetermined angle, and a lamination process is performed along the curved surface or plane. A toolpath for execution is formed. In one embodiment, as shown in FIGS. 7 and 8, each tool path T1 and T2 may be formed only within a portion where the first layer 20 or the second layer 30 is formed. When forming the first layer 20 and the second layer 30 with a constant or constantly changing thickness on the preformed substrate 10, tilting or rotating the substrate 10 or the product through the jig 67 If this is easy and the z-axis movement and rotation of the nozzle 62 can be controlled in detail, durability can be increased by forming the tool path as described above.

Next, the 3D image data can be sliced into multiple planes, and a toolpath can be formed on each plane. When slicing the substrate 10 having a three-dimensional shape into a plurality of planes, as shown in FIGS. 7 and 9, the tool paths T3 and T4 are the first layer region (where the first layer 20 is formed) It is formed over the second layer area (A2), which is the part where A1) and the second layer 30 are formed, and the first layer area (A1) defined according to 3D image data in the mapping step (S20) described later. The second layer area A2 may be mapped on the in-plane toolpath.

The mapping step (S20) is a process of mapping the first layer area and the second layer area defined according to 3D image data to the toolpath. The first layer area and the second layer area defined by coordinates are mapped onto the toolpath. corresponds to When using heterogeneous materials as materials for the lamination process, the first layer area and the second layer area can be mapped to a tool path corresponding to the coordinates along with the component ratio of the material, and at this time, the first layer area can be mapped to the coordinates of each tool path together with the , values corresponding to the second layer area or gas components during the lamination process can be mapped and stored.

The first layer area (A1) and the second layer area (A2) can be defined according to the shape and size of the 3D image data and the results of numerical analysis. The first layer area (A1) is a part that forms a metal layer through the supply of the first material and process gas during the lamination process, and the second layer area (A2) is a part that forms the metal layer through the supply of the second material and first gas during the lamination process. This is the part that forms the metal oxide layer. In one embodiment, a first layer area (A1) of a predetermined thickness is defined on the 3D image data to surround the three-dimensional shaped substrate 10, and a predetermined thickness of the outer portion of the product is defined as a second layer area (A2). It can be defined on 3D image data.

Referring again to FIGS. 2 and 10, the first layer stacking step (S30) is a step of supplying and melting the first material through a nozzle moving along the tool path on one surface to deposit the first layer, as described above. As described above, the first material, which is a metal or alloy powder, is supplied to the first layer area A1 and heated to form a molten pool, and then cooled to form a portion of the first layer as a metal layer. In the first layer stacking step (S30), when the first layer area is mapped on the tool path, the first layer can be formed by supplying the first material and process gas to the tool path. In one embodiment, the first layer stacking step (S30) may form a first layer by supplying a first material on the surface of the substrate 10, but the surface of the first layer 20 or the second layer ( The first layer can be formed by supplying the first material on the surface of 30). That is, as in the case shown in FIG. 8, when the tool path is formed on a curved surface or two or more planes that intersect at a predetermined angle, and the tool path T1 is formed only within the first layer area A1, the first layer area A1 In the first layer stacking step (S30), the first layer can be stacked by supplying and melting the first material on the substrate 10. In comparison, as shown in FIG. 9, the tool paths T3 and T4 are formed on one plane, and the first layer area A1 and the second layer area A2 are mapped simultaneously within one tool path. In this case, in the first layer stacking step (S30), the first layer can be stacked by supplying and melting the first material on the surface of the substrate 10, the first layer 20, or the second layer 30. . The first layer stacking step (S30) includes a first material supply step (S31), a process gas supply step (S33), and a heating step (S35).

The first material supply step (S31) is a process of supplying the first material on the surface of the substrate 10, the first layer 20, or the second layer 30, and the first material supplied from the material supply unit 61 1 This can be performed by supplying the material through the nozzle 62.

The process gas supply step (S33) is a process of supplying process gas through the blower 65 to the area where the first material is supplied. It is performed simultaneously with the first material supply step (S31), so that the process gas is supplied to the area where the first material is supplied. The formation of oxides can be prevented. As described above, the process gas may be an inert gas such as argon or neon, a less reactive gas such as nitrogen may be used, or a mixture of these may be used.

The heating step (S35) is to melt the first material on the surface by heating the area where the first material is supplied, and the first material can be heated through laser irradiation using the heating unit 66.

The gas conversion step (S40) is a process of converting the gas supplied through the blower 65 to the area where the first material or second material is supplied, converting the process gas into the first gas, or converting the supplied gas into the first gas. The first gas can be converted into process gas. The gas conversion step (S40) blocks the process gas supplied from the process gas supply unit 63 to the blower 65 and receives the first gas from the first gas supply unit 64, or the first gas supply unit 64 The flow of the first gas can be blocked and the process gas can be supplied from the process gas supply unit 63. For this purpose, a 3-way valve is installed between the process gas supply unit 63, the first gas supply unit 64 and the blower 65, and the operation of the valve is controlled by the supply control unit 55 so that the supplied gas can be converted. The gas conversion step (S40) is performed when the nozzle 62 moves from the first layer area (A1) mapped on the tool path to the second layer area (A2), from the second layer area (A2) to the first layer area. It is not excluded that it is performed when moving to (A1) and performed multiple times in the method of forming a multi-material structure according to the present invention. In addition, when the lamination process is completed on one toolpath and then the lamination process is started on another toolpath, it may be performed if the information about the first layer and the second layer mapped to each toolpath is different.

The second layer stacking step (S50) is a step of supplying and melting a second material through a nozzle moving along a tool path on one surface to stack the second layer. As described above, the second layer is stacked using a metal or alloy powder. This is the step of heating the second material while supplying it to the second layer area A2 to form a molten pool and then cooling it to form a portion of the first layer as a metal layer. In the second layer stacking step (S50), when the second layer area is mapped on the tool path, the second layer can be formed by supplying the second material and the first gas to the tool path. In one embodiment, the second layer stacking step (S50) may form the second layer by supplying a second material on the surface of the first layer 20, but the surface or substrate of the second layer 30 ( 10) A second layer can also be formed on the surface by supplying a second material. That is, as in the case shown in FIG. 8, when the tool path is formed on a curved surface or two or more planes that intersect at a predetermined angle, and the tool path T2 is formed only within the second layer area A2, the second layer area A2 In the two-layer stacking step (S50), the second layer can be stacked by supplying and melting the second material on the first layer 20. In comparison, as shown in FIG. 9, the tool paths T3 and T4 are formed on one plane, and the first layer area A1 and the second layer area A2 are mapped simultaneously within one tool path. In this case, in the second layer stacking step (S50), the second layer can be stacked by supplying and melting the second material on the surface of the substrate 10, the first layer 20, or the second layer 30. . Accordingly, the first layer stacking step (S30) and the second layer stacking step (S50) may be performed alternately. The second layer stacking step (S50) includes a second material supply step (S51), a first gas supply step (S53), and a heating step (S55).

The second material supply step (S51) is a process of supplying the second material on the surface of the substrate 10, the first layer 20, or the second layer 30, and the second material supplied from the material supply unit 61 2 This can be performed by supplying the material through the nozzle 62.

The first gas supply step (S53) is a process of supplying the first gas through the blower 65 to the area where the second material is supplied, and is performed simultaneously with the second material supply step (S51) to supply the second material. By creating metal oxide along with lamination, the outer surface of the product can be laminated with a metal oxide layer. As described above, the first gas may be oxygen or a gas containing oxygen.

The heating step (S55) is to melt the second material on the surface by heating the area where the second material is supplied, and the second material can be heated through laser irradiation using the heating unit 66.

In another embodiment of the present invention, the first layer stacking step (S30) and the gas conversion step (S40) are omitted, and the second layer stacking step (S50) of stacking the second layer on the substrate 10 is performed. It could be. When the substrate 10 is a metal layer, a second material such as the substrate 10 is laminated on the substrate 10 instead of laminating the first layer, thereby substantially forming a metal oxide layer on the same substrate as the first layer 20. is to form. As described above, in the case of another embodiment d of the present invention, the second layer 30 of zirconia is formed by supplying oxygen along with zirconium powder through the second layer stacking step (S50) on the zirconium substrate 10. A substrate made of metal - can have a structure of a metal oxide layer.

The above detailed description is illustrative of the present invention. Additionally, the foregoing is intended to illustrate preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications can be made within the scope of the inventive concept disclosed in this specification, a scope equivalent to the written disclosure, and/or within the scope of technology or knowledge in the art. The above-described embodiments illustrate the best state for implementing the technical idea of the present invention, and various changes required for specific application fields and uses of the present invention are also possible. Accordingly, the detailed description of the invention above is not intended to limit the invention to the disclosed embodiments. Additionally, the appended claims should be construed to include other embodiments as well.

Claims

A step of supplying and melting a second material through a nozzle moving along a tool path on one surface of a substrate or a first layer formed of a first material, thereby laminating the second layer;

A method of forming a multi-material structure, wherein the second layer is formed of a metal oxide layer.
The method of claim 1, wherein the step of laminating the second layer includes supplying a second material to the surface, supplying a first gas to the area where the second material is supplied simultaneously with the step of supplying the second material. A method of forming a multi-material structure comprising the step of supplying a first gas, wherein the first gas contains oxygen.
The method of claim 2, further comprising supplying and melting the first material through a nozzle moving along a tool path on one surface to deposit the first layer,

The step of laminating the first layer includes a first material supply step of supplying the first material to the surface, and a process gas supply step of supplying a process gas to the area where the first material is supplied simultaneously with the first material supply step. A method of forming a multi-material structure, wherein the process gas includes an inert gas or nitrogen.
The method of claim 3, further comprising a gas conversion step of converting the supplied process gas into the first gas or converting the supplied first gas into the process gas.
The method of claim 4, wherein the first material and the second material are metal powders or alloy powders containing the same metal element.
The method of claim 5, wherein the metal element is one of titanium (Ti), zirconium (Zr), aluminum (Al), copper (Cu), and chromium (Cr).
The method of any one of claims 3 to 6, wherein the step of laminating the first layer includes supplying and melting a first material on a substrate to laminate the first layer, and laminating the second layer. A method of forming a multi-material structure, characterized by supplying a second material on the first layer and supplying a first gas containing oxygen to laminate the second layer of metal oxide.
The method of claim 7, wherein the tool path is formed on a curved surface or two or more planes that intersect at a predetermined angle.
A multi-material structure formed by the method of forming a multi-material structure according to claim 7.
The method according to any one of claims 4 to 6, wherein while the nozzle moves along the tool path, the step of laminating the first layer and the step of laminating the second layer are performed alternately. Method for forming multi-material structures.
The method of claim 10, further comprising a mapping step of mapping the first layer area and the second layer area to the tool path,

A method of forming a multi-material structure, wherein a step of laminating a first layer is performed in a first layer region on the tool path, and a step of laminating a second layer is performed in a second layer region.
The method of claim 11, wherein the gas conversion step converts the gas supplied when the nozzle moving along the tool path enters the first layer area into the second layer area from the process gas to the first gas, and the nozzle converts the gas into the first gas. A method of forming a multi-material structure, characterized in that the gas supplied when entering the first layer area from the second layer area is converted from the first gas to a process gas.
A multi-material structure formed by the method for forming a multi-material structure according to claim 10.