KR102163113B1 - Metal wire 3d printer - Google Patents

Abstract

The present invention relates to a metal wire 3D printer capable of 3D printing a metal material such as titanium without using a chamber while providing a metal material in a wire form, comprising: a stage on which metal materials are laminated; A laser device positioned above the stage and irradiating a laser downward to melt a metal material; A feeding device for supplying a metal material in the form of a wire to a focal position of the laser irradiated by the laser device; And a shielding jig for injecting a shielding gas at a focal position of the laser, wherein the shielding jig has a through portion through which the laser irradiated by the laser device and the metal wire supplied from the feeding device pass, and a lower surface thereof is formed in the laser device. It is located relatively higher than the focal point of the irradiated laser, and is characterized in that the shielding gas is injected through the injection hole formed on the lower surface.
The present invention has the effect of 3D printing by providing a metal material that is easily deteriorated such as titanium by a shielding jig in a wire form without a chamber. Furthermore, by 3D printing titanium without a chamber, there is an excellent effect that products such as propellant tanks can be manufactured by 3D printing without size limitation.

Description

Metal wire 3D printer {METAL WIRE 3D PRINTER}

The present invention relates to a 3D printer, and more particularly, to a 3D printer for laminating metal materials in three dimensions.

In general, a 3D printer is a printing technology that can make a specific product three-dimensional, and refers to a method or device that can create an actual product by laminating material materials in a three-dimensional space as if printing on paper using a three-dimensional design. .

For such 3D printing, since a method of solidifying after melting is applied to laminate material materials, polymers are generally used in 3D printers. However, due to the limitations of material materials, the scope of application was limited, and research for 3D printing of metal materials with excellent physical properties is ongoing.

As a technology for 3D printing a metal material, DED (direct energy deposition) and DMT (laser-aided direct metal tooling) technologies are recently applied. Unlike conventional SLA or SLS, where metal powder is spread over the entire stage and a part is melted and bonded, metal powder that is discharged only to the required part is melted and laminated with a high energy source such as a laser and e-beam. Since the DED and DMT have to be melted and laminated immediately after the metal powder is discharged, the structure of the nozzle is limited such as that the protective gas and metal powder must be discharged from the nozzle, and the laser used is also limited. Furthermore, since the protective gas discharged from the nozzle affects only the metal powder, it is generally performed inside the chamber to protect the entire metal component.

On the other hand, titanium is highly utilized in fields such as aerospace, aviation, and bio/medical due to the excellent properties of the material, but due to the nature of the material, it is difficult to apply general metal processing technology and thus its use is limited. Accordingly, efforts are being made to 3D print titanium, but it is difficult to apply due to the rapidly oxidizing property, and there is a disadvantage in that it is not possible to manufacture large-sized products because 3D printing is performed in the chamber to prevent oxidation, such as DED or DMT described above.

Republic of Korea Patent Publication 10-2018-0003141

An object of the present invention is to provide a metal wire 3D printer capable of 3D printing a metal material such as titanium without using a chamber while providing a metal material in the form of a wire. .

A metal wire 3D printer according to the present invention for achieving the above object comprises: a stage on which a metal material is laminated; A laser device positioned above the stage and irradiating a laser downward to melt a metal material; A feeding device for supplying a metal material in the form of a wire to a focal position of the laser irradiated by the laser device; And a shielding jig for injecting a shielding gas at a focal position of the laser, wherein the shielding jig has a through portion through which the laser irradiated by the laser device and the metal wire supplied from the feeding device pass, and a lower surface thereof is formed in the laser device. It is located relatively higher than the focal point of the irradiated laser, and is characterized in that the shielding gas is injected through the injection hole formed on the lower surface.

It is preferable that the shielding jig is fastened to the laser device and moved together.

It is preferable that the feeding device supplies a metal wire in a side direction of the laser irradiated downward from the laser device, and the penetrating portion of the shielding jig has a side open in a direction in which the feeding device is located.

It is preferable that the shielding jig sprays the shielding gas to the stacked portion where the laser focus has passed based on the moving direction of the laser focus.

It is preferable that the shielding jig sprays the shielding gas in front of the focal point of the laser based on the moving direction of the laser focus.

The shielding jig may be made of titanium.

A cooling device for cooling the shielding jig or the shielding gas may be further included.

In the present invention configured as described above, by applying a shielding jig configured separately from the laser device, there is an effect that 3D printing can be performed without using a chamber while providing a metal material in a wire form.

In addition, there is an effect of 3D printing by providing a metal material that is easily deteriorated such as titanium by the shielding jig in the form of a wire without a chamber.

Furthermore, by 3D printing titanium without a chamber, there is an excellent effect that products such as propellant tanks can be manufactured by 3D printing without size limitation.

1 is a view for explaining the configuration of a metal wire 3D printer according to an embodiment of the present invention.
FIG. 2 is a view showing a view of the shielding jig as viewed from the top to the bottom in order to explain the arrangement relationship between the shielding jig and other components of the present embodiment.
3 is a view showing the lower surface of the shielding jig in order to explain the injection hole of the shielding jig according to the present embodiment.
4 is a view for explaining the printing operation of the metal wire 3D printer of the present embodiment.
5 is a photograph of a laminate in which titanium is laminated in three dimensions using a metal wire 3D printer according to an embodiment of the present invention.
6 is a photograph of a cross-section of a laminate manufactured using a metal wire 3D printer according to an embodiment of the present invention.
7 is a photograph of a cross-section of stacked insects stacked without supplying shielding gas to the shielding jig for comparison.

An embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

However, the embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. The shapes and sizes of elements in the drawings may be exaggerated for clearer description, and elements indicated by the same reference numerals in the drawings are the same elements.

And throughout the specification, when a part is "connected" to another part, this includes not only the case of being "directly connected", but also the case of being "electrically connected" with another element interposed therebetween. In addition, when a part "includes" or "includes" a certain component, it means that other components are not excluded and other components may be further included or provided unless otherwise specified. do.

In addition, terms such as "first" and "second" are used to distinguish one component from other components, and the scope of the rights is not limited by these terms. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component.

1 is a view for explaining the configuration of a metal wire 3D printer according to an embodiment of the present invention.

As shown, the 3D printer of this embodiment includes a stage 100, a laser device 200, a feeding device 300, and a shielding jig 400.

The stage 100 is a basis on which 3D printing is performed, and a product is manufactured by laminating a 3D-printed metal material.

The laser device 200 is a device that generates a laser L, which is an energy source for melting a metal material, and is positioned above the stage 100 to vertically move the laser L toward the stage 100 disposed below. It is arranged to irradiate in the direction. In the present invention, since the metal material is provided in a wire form rather than a powder form, the focal length of the laser device 200 can be sufficiently used. In this embodiment, the distance from the end of the laser device 200 to the focal point is 163 mm, and the DED Compared to the nozzles that discharge metal powders in and DMT, a high-energy laser device can be applied. The laser device 200 is connected to a moving device capable of moving in a three-axis direction so that a three-dimensional product can be manufactured by laminating metal materials. However, since the movement of the laser device 200 is a relative movement with respect to the stage 100, the laser device 200 may be fixed and the stage 100 may move.

The feeding device 300 is a device for providing a metal material in the form of a wire, and various techniques of continuously providing the metal wire W in the focus of the laser L may be applied. In particular, a feeding device with an arc torch function that generates an arc can be applied. The feeding device 300 includes a metal wire in the lateral direction of the laser L path so that the end of the metal wire W can be provided at the focal point of the laser L irradiated from the top of the stage 100 downward. W) is provided, and it is generally arranged diagonally obliquely so that the end of the metal wire W is located at the bottom. The feeding device 300 should always have a fixed positional relationship with the laser device 200 so that the metal wire W can be provided at the focal point of the laser L. In addition, when the laser device 200 moves to stack metal materials in the form of a three-dimensional product only when the positional relationship with the laser device 200 is fixed, the feeding device 300 also moves according to the movement of the laser device 200. While it is possible to provide a metal wire (W) to the focus of the laser (L). Therefore, the laser device 200 and the feeding device 300 may be combined with separate brackets so that the positional relationship between the laser device 200 and the feeding device 300 can be fixed to each other. Meanwhile, in the present specification, the metal material supplied to the focal point of the laser L is expressed in the form of a wire, but may also be expressed in the form of a filament, which is a similar expression.

The shielding jig 400 is a device for preventing deterioration of a metal material by discharging a shielding gas to a portion where the metal wire W is melted and laminated. Unlike conventional DED and DMT discharging metal powder, the 3D printer of this embodiment uses a metal wire (W), and accordingly, the focus of the laser (L) and A gap is formed between the laser devices 200. Therefore, it is impossible to eject the protective gas in the same manner as DED and DMT, and in this embodiment, a separate shielding jig 400 is applied. The shielding jig 400 is fixed in a position relative to the laser device 200 by the fastening part 410, and the shielding gas is continuously supplied from the outside and discharged downward. The supply of the shielding gas may be directly injected into the shielding jig 400 or may be injected through the fastening part 410. As will be described in detail later, the height of the lower surface of the shielding jig 400 is positioned higher than the focus of the laser L, and the shielding gas can be discharged toward the focus of the laser L by discharging the shielding gas downward. .

2 to 4 are views for explaining a shielding jig applied to a metal wire 3D printer according to an embodiment of the present invention.

FIG. 2 is a view showing a view of the shielding jig as viewed from the top to the bottom in order to explain the arrangement relationship between the shielding jig and other components of the present embodiment.

As shown, the shielding jig 400 has a through portion 420 formed so that the laser L irradiated from the laser device 200 can pass and reach the lower stage 100, and the shielding jig ( The body of 400) surrounds the through part 420. Since the through part 420 is not only a space through which the laser L passes, but also a space providing the metal wire W, the through part 420 is disposed diagonally to the end of the metal wire W as the focus of the laser L. In accordance with the configuration of the feeding device 300 provided to, the through part 420 is configured in a form in which one side direction is open. In this way, despite the additional application of the shielding jig 400 by the structure of the through portion 420 opened in one side direction, there is no limitation in the configuration of the feeding device 300.

3 is a view showing the lower surface of the shielding jig in order to explain the injection hole of the shielding jig according to the present embodiment.

The shielding gas supplied to the shielding jig 400 is sprayed toward the focal point of the laser L through the injection hole 430 formed on the lower surface. The configuration shown in FIG. 3 is an arrangement structure suitable for laminating metal materials while the laser device 200 moves toward the direction in which the feeding device 300 is positioned. At this time, the arrangement of the injection hole 430 may be variously configured and is not limited to the illustrated shape, but for precise lamination, the laser device 200 and the feeding device 300 move in the above-described direction to perform printing. It is common to do. As a result, since the through part 420 opened in one side direction is formed parallel to the progress direction of the laser device 200 and the feeding device 300, the injection hole 430 is disposed around the through part 420 I did. At this time, the shielding gas may be simultaneously ejected from the injection holes 430 arranged in the longitudinal direction, or the injection holes may be grouped according to the position so that the injection hole group may be configured to control whether or not the shielding gas is ejected. have.

4 is a view for explaining the printing operation of the metal wire 3D printer of the present embodiment.

The stack 1000 is stacked on the stage 100 in a way that the laser L melts the metal wire W, and an additional layer 1100 at the focal height of the laser L above the existing stack 1000 ) Is shown to be newly stacked.

When the shielding gas 500 supplied to the inside of the shielding jig 400 is sprayed downward through the spray hole 430 formed on the lower surface, the shielding gas 500 reaches the focal portion of the laser L and is melted and stacked. Prevents deterioration of metal materials. At this time, the distance between the lower end of the shielding jig 400 and the focal point of the laser L is adjusted in the range of 5 to 10 mm so that the shielding gas 500 can reach the newly stacked portion.

And, as described above, in this embodiment, since the injection holes 430 are long arranged in the moving direction of the laser device 200 and the feeding device 300, not only the focal part of the laser L but also the laser L The shielding gas is also injected into the part where the focus of This is because the metal wire maintains a fairly high temperature state even after the metal wire is melted and then laminated, so that a metal material such as titanium, which is easily oxidized, is liable to deteriorate. For this reason, in the conventional DED and DMT, which discharge the protective gas only to the nozzle from which the metal powder is discharged, it is common to perform 3D printing in a chamber blocked from the outside. However, in this embodiment, since the shielding gas 500 is sprayed even at the portion where the focus of the laser L has passed, the metal material by the shielding gas 500 until the temperature of the newly stacked additional layer 1100 is sufficiently lowered. Can obtain the effect of preventing deterioration of Due to the structure of the shielding jig 400, the 3D printer of this embodiment is not forced to perform printing in the chamber, and 3D printing is also applied to products that have not previously applied 3D printing due to the size of the chamber. There is an advantage to be able to do.

In this way, the long-arranged injection holes 430 are inside the shielding jig 400 so that the shielding gas 500 can be evenly sprayed to the focal portion of the laser (L) and the focal portion of the laser (L). A plurality of flow paths may be formed or a network structure may be installed.

In addition, the elongated injection holes 430 spray the shielding gas 500 even at a position before the focus of the laser L passes, and this has a shielding effect on the laminated portion in the 3D printer of the present embodiment not using a chamber. It shows the effect of heightening.

On the other hand, the shielding jig 400 may be affected by heat by being located close to the focal point of the laser (L) generating high temperature in the range of 5 to 10 mm, and when the temperature of the shielding gas 500 is low, it is laminated with a shielding effect. Since the effect of rapidly cooling the water 1000 may be obtained, a cooling device (not shown) for cooling the shielding jig 400 or the shielding gas 500 may be additionally provided.

Among the products in the aerospace and aviation fields using titanium, there is a propellant tank. In order to manufacture a propellant tank using titanium, which is difficult to process, the casting method was conventionally applied.However, the casting process itself was very difficult because of the high melting point and easy oxidation due to the nature of titanium, and the cost of manufacturing the mold was high and the size was limited. There was a downside to being. In order to solve this problem, there has been an attempt to manufacture a titanium propellant tank by 3D printing, but it is difficult to apply because the size of the product is more limited due to the limitations of DED and DMT that must perform 3D printing in the chamber.

On the other hand, if the 3D printer of the present invention, which does not require the use of a chamber, is applied, a titanium propellant tank can be manufactured without limitation in size. At this time, the shielding jig is made of a titanium material to block the possibility of contamination due to the use of other metal materials.

5 is a photograph of a laminate in which titanium is laminated in three dimensions using a metal wire 3D printer according to an embodiment of the present invention. 6 is a photograph of a cross-section of a laminate manufactured using a metal wire 3D printer according to an embodiment of the present invention, and FIG. 7 is a cross-sectional view of a stacked pile without supplying a shielding gas to the shielding jig for comparison. This is one picture.

As shown in FIG. 5, it can be seen that a three-dimensional laminate can be stacked using a wire-shaped titanium using the 3D printer of this embodiment.

As shown in FIG. 6, it can be seen that the titanium laminate laminated while spraying the shielding gas from the shielding jig using the 3D printer of the present embodiment was not oxidized even though it was laminated in a device without a chamber. On the other hand, in the case of FIG. 7 in which the shielding gas is not injected from the shielding jig, it can be seen that oxidation has progressed due to an effect that has not been performed in the chamber.

As described above, in the case of three-dimensional stacking without a chamber, it is generally not applicable to the propellant tank due to oxidation, but using the 3D printer of this embodiment allows non-oxidized titanium to be stacked without a chamber. Therefore, it can be seen that it is suitable for manufacturing a propellant tank.

The present invention has been described above through preferred embodiments, but the above-described embodiments are only illustrative of the technical idea of the present invention, and various changes are possible within the scope not departing from the technical idea of the present invention. Those of ordinary knowledge will understand. Therefore, the scope of protection of the present invention should be interpreted not by specific embodiments, but by the matters described in the claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

100: stage
200: laser device
300: feeding device
400: shielding jig
410: fastening part
420: through part
430: injection hole
500: shielding gas
L: laser
W: metal wire

Claims (7)

A stage on which a metal material is laminated;
A laser device positioned above the stage and irradiating a laser downward to melt a metal material;
A feeding device for supplying a metal material in the form of a wire to a focal position of the laser irradiated by the laser device;
It includes a shielding jig that injects shielding gas at the focal position of the laser,
The shielding jig has a fastening portion fastened to and coupled to the laser device at an upper portion, and a laser irradiated from the laser device and a metal wire supplied from the feeding device pass through a lower portion extending and disposed below the laser device. A through part is formed, the lower surface is positioned relatively higher than the focal point of the laser irradiated by the laser device, and the shielding gas supplied to the inside of the shielding jig is injected through a plurality of injection holes formed on the lower surface,
The feeding device supplies a metal wire in the lateral direction of the laser irradiated downward from the laser device,
Metal wire 3D printer, characterized in that the through portion of the shielding jig has a side open in a direction in which the feeding device is located.
The method according to claim 1,
Metal wire 3D printer, characterized in that the shielding jig is fastened to the laser device and moved together.
delete The method according to claim 1,
Metal wire 3D printer, characterized in that the shielding jig injects a shielding gas to a stacked portion where the laser focus has passed based on the moving direction of the laser focus.
The method according to claim 1,
Metal wire 3D printer, characterized in that the shielding jig injects a shielding gas even in front of the focal point of the laser based on the moving direction of the laser focus.
The method according to claim 1,
Metal wire 3D printer, characterized in that the shielding jig is made of titanium.
The method according to claim 1,
Metal wire 3D printer, characterized in that it further comprises a cooling device for cooling the shielding jig or the shielding gas.

Images