KR101787718B1 - 3-dimensional laser printing apparatus and method - Google Patents

Abstract

According to one embodiment of the present invention, a three-dimensional laser printing apparatus which laminates a clad layer by melting powder using a laser beam output from an optical system is disclosed, wherein the optical system comprises: a first laser beam having a beam intensity capable of melting powder and irradiating a surface of an object to be laminated; and a second laser beam having a beam intensity enough to heat a laminated clad layer without being re-melted and irradiating the surface of the object to be laminated in a shape surrounding the first laser beam. According to one embodiment of the present invention, a laser beam for processing for forming a molten pool and for laminating a clad layer, and a laser beam for heating for heating the periphery of the molten pool to prevent quenching of the clad layer at the periphery of the molten pool can be simultaneously provided.

Description

The present invention relates to a three-dimensional laser printing apparatus and method,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional laser printing method and apparatus, and more particularly, to a three-dimensional laser printing method and apparatus using three-dimensional laser printing method using a laser cladding technique for producing a three-dimensional projected product by supplying powder of a clad material to a specimen, Dimensional laser printing method and apparatus.

Laser cladding or metal 3D printing technology is a technique of obtaining a two-dimensional cross-sectional information from three-dimensional data for CAD (Computer-Aided Design) for a three-dimensional object to be produced and laminating each cross- to be.

In this technique, two-dimensional cross-sectional information having a predetermined thickness is calculated from three-dimensional CAD data, and clad layers having a shape and thickness corresponding to each two-dimensional cross-sectional information are sequentially laminated to form a three- I make it. That is, a technique of fabricating a three-dimensional shape by laminating two-dimensional planes one layer at a time.

In this method, for example, a laser light output stage 10 is disposed on a test piece 20 (or a substrate or a base material) as shown in FIG. 1, and laser light is irradiated on the laser light output stage 10 A melting pool is locally formed in the specimen 20 and a clad material in the form of powder (for example, metal, alloy, ceramic, or the like) is supplied to the region to laminate the clad layer on the surface of the specimen 20 do. At this time, the laser light output stage 10 and the supply nozzle (not shown) for supplying the powder are integrally stacked on the specimen 20 and move along a zigzag or any other stacking path on the specimen 20 to stack the clad layer on the specimen 20, As a result, the clad layers 31, 32, and 33 are formed on the test piece 20 as shown in FIG.

However, in the conventional laser cladding method, when the laser light output terminal 10 is moved along the path and the powder is melted and the clad layer is laminated, the laser light output stage 10 passes, and the clad layer region just stacked is rapidly cooled The rapid cooling of the clad layer formulations is apt to break.

In order to solve this problem in the past, a method of disposing a heating means under the specimen 20 and continuously heating the specimen 20 as a whole during the step of laminating the clad layer to prevent the clad layer from being cooled quickly is also used . However, in order to heat the entire specimen, there is a problem that the power consumption increases and the apparatus becomes complicated. Further, as the height of the clad layer is increased, the heat transmitted from the lower part to the upper clad layer gradually decreases.

Korean Published Patent Application No. 2003-0039929 (published on May 22, 2003)

According to one embodiment of the present invention, a laser beam for processing for forming a molten pool and for laminating a clad layer and a laser beam for heating for heating the periphery are simultaneously provided to prevent quenching of the clad layer around the molten pool A three-dimensional laser printing apparatus and method are disclosed.

According to one embodiment of the present invention, the first laser light for processing is irradiated on the surface of the object to be laminated, and at the same time, the second laser light for heating is irradiated on the surface of the object to be laminated so as to surround the first laser light A three-dimensional laser printing apparatus and method are disclosed.

According to an embodiment of the present invention, there is provided a three-dimensional laser printing apparatus for melting a powder with laser light output from an optical system to laminate clad layers, wherein the optical system has a light intensity capable of melting powder, A first laser beam irradiating the surface of the first laser light; And a second laser light having a light intensity enough to heat the laminated clad layer without re-melting, and irradiating the surface of the object to be laminated in a shape surrounding the first laser light; A printing apparatus is provided.

According to an embodiment of the present invention, there is provided a three-dimensional laser printing apparatus for melting a powder with laser light output from an optical system to laminate a clad layer, wherein laser light generated in the laser light source is emitted as a first laser light and a second laser light A beam splitter for splitting the beam splitter; An optical device for making the second laser light into a shape surrounding the first laser light; And a beam combiner for aligning and coupling the first laser beam and the second laser beam with respect to one optical axis.

According to an embodiment of the present invention, there is provided a three-dimensional laser printing apparatus for melting a powder with laser light output from an optical system to laminate a clad layer, comprising: a first laser light source for generating a first laser light; A second laser light source for generating a second laser light; An optical device for making the second laser light into a shape surrounding the first laser light; And a beam combiner for aligning and coupling the first laser beam and the second laser beam with respect to one optical axis.

According to an embodiment of the present invention, there is provided a three-dimensional laser printing method for laminating clad layers by melting powders with laser light output from an optical system, the laser light being generated by a laser light source, ; Adjusting the second laser light to light having a shape surrounding the first laser light; Aligning the first laser light and the second laser light by aligning them with respect to one optical axis; And simultaneously irradiating the surface of the object to be laminated with the first and second laser beams.

According to an embodiment of the present invention, there is provided a three-dimensional laser printing method of laminating clad layers by melting powders with laser light output from an optical system, the method comprising: generating first laser light and second laser light; Adjusting the second laser light to light having a shape surrounding the first laser light; Aligning the first laser light and the second laser light by aligning them with respect to one optical axis; And simultaneously irradiating the surface of the object to be laminated with the first and second laser beams.

According to an embodiment of the present invention, by irradiating a laser beam for processing for laminating a clad layer toward a molten pool and at the same time for irradiating a laser beam for heating to prevent quenching of the clad layer around the molten pool, It is possible to provide an effect of preheating the region and to prevent the quenching of the cladding layer in the already deposited region.

1 and 2 are views for explaining a conventional three-dimensional laser printing method,
3 is a view for explaining laser light generated according to an embodiment of the present invention,
4 is a diagram for explaining the light intensity of the laser light of FIG. 3,
5 is a diagram for explaining laser light generated according to an alternative embodiment,
FIG. 6 is a view for explaining laser light generated according to another alternative embodiment; FIG.
7 is a view for explaining a three-dimensional laser printing apparatus according to an embodiment,
8 is a view for explaining an optical system according to the first embodiment,
9 is a view for explaining an optical system according to a second embodiment,
10 is a view for explaining an optical system according to the third embodiment,
11 is a flowchart illustrating a laser light generating and irradiating method according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description of preferred embodiments with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In this specification, when an element is referred to as being on another element, it means that it can be formed directly on the other element, or a third element may be placed therebetween.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. The terms "comprises" and / or "comprising" used in the specification do not exclude the presence or addition of one or more other elements.

Also, terms such as " ... part ", "module "," ... board ", "... block ", etc. used to refer to components of the invention are used herein to describe at least one function or operation Unit, which may be implemented in hardware, software, or a combination of hardware and software.

Hereinafter, the present invention will be described in detail with reference to the drawings. In describing the specific embodiments below, various specific details have been set forth in order to explain the invention in greater detail and to assist in understanding it. However, it will be appreciated by those skilled in the art that the present invention may be understood by those skilled in the art without departing from such specific details. In some instances, it should be noted that portions of the invention that are well known in the description of the invention and not significantly related to the invention do not describe confusion in describing the present invention.

FIG. 3 is a view for explaining laser light generated according to an embodiment of the present invention. FIG. 3 (a) is a plan view of a laser light output from the laser light output stage 10, And FIG. 3 (b) is a view of the laser light 40 irradiated on the surface of the clad layer 30 from above.

7, a laser light output stage 10 is attached to a head unit (for example, 100 in FIG. 7) of a three-dimensional laser printing apparatus according to an embodiment, and laser light 40 ) Is irradiated toward the object to be laminated (for example, the clad layer 30).

The laser light 40 according to an embodiment of the present invention may be composed of a first laser light 41 and a second laser light 43. As shown in the figure, the first laser beam 41 is a laser beam which is irradiated on the surface of the object to be laminated in a circular shape with a predetermined diameter. The irradiation region irradiated with the first laser light 41 is indicated by "Ap" in the figure. The first laser light 41 has a light intensity enough to melt a powdery cladding material (for example, a metal, an alloy, or a ceramic powder). When the powder of the cladding material is injected into the irradiation area Ap of the first laser light, the powder is melted by the first laser light 41 to form a melting pool.

The second laser light 43 is a laser light that is irradiated in a ring shape (or donut shape) surrounding the first laser light 41, Quot; Ah ". The second laser light 43 has a light intensity enough to heat the laminated clad layer without re-melting. The irradiation area Ah of the second laser light 43 has the same optical axis 45 as that of the first laser light 41 and has an irradiation area Ap of the first laser light 41 As shown in Fig.

In the illustrated embodiment, the radius of the inner peripheral surface of the ring-shaped irradiation area Ah from the optical axis 45 is larger than the radius of the outer peripheral surface of the circular irradiation area Ap, And the irradiation area Ah of the second laser light do not overlap with each other. However, in an alternative embodiment, a part of the irradiation area Ap of the first laser light and the irradiation area Ah of the second laser light may overlap.

Fig. 4 is a diagram for explaining the light intensity of the laser light of Fig. 3; Fig. In Fig. 4, the vertical axis represents the light intensity and the horizontal axis represents the distance (radius) from the optical axis 45. In the drawing, the first laser light 41 is indicated by a solid line, the second laser light 43 is indicated by a dotted line, and the graphs of the light intensities of the first laser light and the second laser light are diagrammatic for explanation, It can be different from the intensity graph.

Referring to the drawing, the first laser light 41 has the largest light intensity on the optical axis 45, and the intensity becomes weaker as the distance from the center increases. At this time, up to a radius having a light intensity capable of melting the powder is indicated by the irradiation area Ap of the first laser light. In the illustrated embodiment, the first laser light 41 can be implemented as collimated light, and the first laser light 41 can have a substantially constant light intensity within the irradiation area Ap.

The second laser beam 43 is irradiated in a ring shape (or donut shape), and as shown in the drawing, the second laser beam 43 has the largest light intensity in a region spaced a certain distance from the optical axis 45 . In one embodiment shown, the second laser light 43 may be implemented as collimated light. The second laser light 43 has a light intensity lower than that of the light enough to melt the cladding powder and is used for heating the object to be laminated (for example, the specimen 20 or the vapor-deposited cladding layer 30) .

In addition, the second laser light 43 may preheat the clad powder. For example, when the powder for clad is injected toward the molten pool (for example, the same area as the irradiation area Ap), the powder to be injected passes through the irradiation area of the second laser light 43, The powder is preheated in the course of passing through the second laser light 43 and then can be dropped into the molten pool.

Thus, by irradiating the second laser light 43 in the form of a ring around the first laser light 41 in the form of a molten pool, it is possible to heat the region surrounding the molten pool among the objects to be laminated, There is an effect of preheating the object to be laminated beforehand in the area not yet stacked on the front side (that is, the front area on the progress path of the laser light output stage 10), and the mirrors layered area immediately after the fused pool 10), the mirror-clad clad layer is maintained at a predetermined temperature for a predetermined period of time without cooling immediately, and then gradually cooled to prevent the clad layer from being easily broken due to quenching of the laminated clad layer can do.

Further, since the second laser light 43 is irradiated in the ring shape around the molten pool, even if the laser light output stage 10 moves in any direction, the second laser light 43 has a preheating function for the front region in the traveling direction, The anti-quenching function can be exhibited.

On the other hand, known optical means can be used to make such ring-shaped second laser light. For example, an optical means such as an axicon lens, an optical vortex phase plate, or a Galvano scanner can be used to produce ring-shaped laser light.

5A is a top view of the laser light 40 irradiated on the surface of the cladding layer 30, and FIG. 5B is a cross- b) is a diagram for explaining the light intensity of the laser light.

Compared with the embodiment of Figs. 3 and 4, in the embodiment of Fig. 5, the first laser light 41 and the second laser light 43 are partially overlapped and irradiated. That is, the boundary portion of the circular irradiation region Ap of the first laser beam 41 and the inner boundary portion of the ring-shaped irradiation region Ah of the second laser beam 43 partially overlap each other, You can investigate.

According to this embodiment, even when the boundary portion of the irradiation area Ap of the first laser beam 41 does not have a light intensity as strong as the central portion (i.e., the region near the optical axis 45) Since the boundary portion of the second laser light 43 overlaps the irradiation region Ah of the second laser light 43, the light intensity can be stronger by the center portion of the irradiation region Ap and energy sufficient to form a molten pool over the entire irradiation region Ap Can be provided.

FIG. 6 is a view for explaining laser light generated according to another alternative embodiment. FIG. 6A, a circular irradiation area Ap having a predetermined diameter is formed on the surface of the object to be laminated by the first laser light 41, and the second laser light 43 is irradiated with the first laser An irradiation area Ah having an elliptical shape around the light 41 is formed.

6 (b) shows another example in which a quadrangular (for example square or rectangular) irradiation area Ap is formed on the surface of the object to be laminated by the first laser light 41 and the second laser light 43 And an irradiation region Ah surrounding the first laser light in a rectangular shape is formed by the first laser light. Since a rectangular or rectangular beam is formed instead of a circular laser beam in order to process a large area in a short time, 3D printing may be performed. In this case, the second laser light for heating may be rectangular . In other words, the second laser light 43 does not necessarily have to be irradiated in a ring shape. According to a specific embodiment, the second laser light is surrounded by the first laser light 41 in an arbitrary shape such as an ellipse, It will be appreciated if it is investigated.

3 to 5, the first laser beam 41 is a light beam having a predetermined diameter and the second laser beam 43 is a first laser beam 43 The following embodiments will be described.

An exemplary three-dimensional laser printing apparatus capable of generating and irradiating the first and second laser beams 41, 43 described above with reference to FIG. 7 will now be described.

Referring to FIG. 7, a three-dimensional laser printing apparatus according to an embodiment may include a laser light source 50, a powder feeder 60, a head unit 100, a stage 200, and a control unit 300 have.

The laser light source 50 is a device for generating a laser light to be irradiated on the test piece 20, and the generated laser light passes through the optical path in the head unit 100 and is output from the laser light output end 10. The laser light output from the laser light output stage 10 is irradiated to the specimen 20, and a clad layer is stacked on the specimen 20.

Here, the test piece 20 is a basic material in which a clad layer is laminated and is also called a " substrate ". The material of the test piece 20 is not limited, and for example, low carbon steel, low alloy steel, stainless steel, aluminum, cast iron, tool steel, superalloy and the like can be used.

The powder feeder 60 is a device for storing a clad powder serving as a component of the clad layer to be laminated on the specimen 20 and supplying the clad powder to the specimen 20. The powder feeder 60 includes a powder feed nozzle 65 connected to the end of the feed pipe 61, Lt; / RTI > The powder to be used at this time may be a variety of materials such as, for example, Stellite, tungsten alloy, cobalt and nickel alloy, copper alloy, ceramic and the like. The kind of metal, alloy and ceramic is not particularly limited.

It is desirable that the laser light output terminal 10 and the powder supply nozzle 65 move integrally and therefore the laser light output terminal 10 and the supply nozzle 65 are attached to the head unit 100 and move integrally . ≪ / RTI >

Examples of the method of spraying the powder toward the irradiation area (melting pool) of the laser light in the powder supply nozzle 65 include a method of supplying the powder by a lateral powder-feeding method, a centrifugal powder- .

In the side powder feeding method, the powder feed nozzle 65 is disposed on at least one side surface around the laser light output stage 10. This method is a method of supplying powder to the molten pool from any one side of the side with reference to the laser light. The loss rate of the powder can be reduced according to the designing method of the supply nozzle 65 and the relatively thick clad layer 30 is formed . However, since there is an anisotropy in which the shape and height of the cladding layer 30 change depending on the direction of cladding (i.e., the direction of movement of the specimen 20 or the laser beam), there is a disadvantage in that there is a limitation in the lamination path. The centrifugal-type powder supply system is arranged such that the powder supply nozzle 65 concentrically surrounds the laser light output stage 10 so that the powder can be uniformly supplied to the molten pool from all directions around the laser light. In one embodiment of the present invention, the above-described centrifugal powder feed method or a plurality of (for example, about three) powder feed nozzles may be used, but the present invention is not limited to this configuration.

A nozzle for supplying shielding gas such as argon into the molten pool and a cooling water supply pipe for cooling the laser light output stage 10 are provided in the laser light output stage 10 ). ≪ / RTI >

The test piece 20 can be supported and fixed on the stage 200. [ The head unit 100 and the stage 200 must be able to move relative to each other in the X, Y, and Z-axis directions in order to stack the clad layer on the surface of the test piece 20. To this end, in one embodiment, the stage 200 is fixed and the head unit 100 can be driven in the X, Y, Z directions. In another embodiment, the head unit 100 may be fixed and the stage 200 may be driven in the X, Y, and Z directions. In another embodiment, the head unit 100 and the stage 200 may be driven in X, Y, , Or in the Z direction. Each of the head unit 100 and / or the stage 200 can be driven by a driving device (not shown), which can move the head unit 100 and / or the stage 200 to X, Y, Z And may be constituted by a driving motor or a driving cylinder which drives each direction.

The control unit 300 calculates the two-dimensional cross-sectional information from the CAD data of the molding to be formed by the lamination of the clad layers, and sets and stores the lamination process for each of the clad layers based on the respective two-dimensional cross-sectional information. Variables included in the laminating process for laminating the respective clad layers may include at least one of, for example, a lamination path, an output of the laser light, a supply amount of the powder, and a relative speed between the head unit and the stage.

Thereafter, the control unit 300 supplies control signals for the stacking path, the laser light output, the powder supply amount, and the relative speed between the head unit and the stage to the laser light source 50, the powder supply unit 60, (100), and the stage (200), respectively, so that the clad layers can be stacked.

In the three-dimensional laser printing apparatus according to an embodiment of the present invention, the head unit 100 receives the laser light from the laser light source 50 and transmits the first laser light 41 and the second laser light 43 from the laser light source 50 Optical system. As described with reference to Figs. 3 to 5, the first laser light 41 is a laser light having a light intensity capable of melting powder and irradiated in a circular shape with a predetermined diameter on the surface of the object to be laminated, The light 43 is a laser light having a light intensity enough to heat the laminated clad layer without being remelted and irradiated in a ring shape surrounding the first laser light 41 on the surface of the object to be laminated. As described with reference to FIG. 6, it is needless to say that the shape of the first laser light and the second laser light may be different in the alternative embodiment.

In one embodiment, the optical system in the head unit 100 may include a beam splitter and a beam combiner to produce a first laser beam 41 and a second laser beam 43. The beam splitter can divide the laser light generated by the laser light source 50 into the first laser light and the second laser light, and the beam combiner divides the first laser light and the second laser light with reference to one optical axis They can be aligned and combined. The combined first and second laser beams are irradiated toward the stacking object (for example, the specimen 20 or the vapor-deposited cladding layer 30) after the focus is adjusted through the optical means such as one or more lenses.

In an alternative embodiment, the laser light source 50 may include two laser light sources. Each of the laser light sources generates a first laser light 41 and a second laser light 43. The optical system in the head unit 100 receives the first laser light and the second laser light, And then irradiated toward the stacking object.

Hereinafter, a plurality of exemplary optical system configurations will be described in turn with reference to FIGS. 8 to 10. FIG.

8 schematically shows an optical system according to the first embodiment.

Referring to the drawings, an optical system according to one embodiment may include a beam splitter 120, a beam combiner 130, an optical device 170 to render the laser light into a ring shape, and a plurality of optical means 110,140,150,160. have.

In one embodiment, the optical means 110 is a collimating lens, and the laser light generated by the laser light source 50 may be collimated light while passing through the optical means 110. The optical means 110 may be omitted if the laser light generated and output by the laser light source 50 is collimated light. As another example, it is needless to say that the optical means 110 can be omitted even when it is not necessary to irradiate the object to be laminated with the collimated light.

The laser beam having passed through the optical means 110 is divided into a first laser beam 41 and a second laser beam 43 by the beam splitter 120. The beam splitter 120 may include, for example, a dichroic lens (filter), and may be implemented by other known techniques.

At this time, the first laser beam 41 has a light intensity capable of melting the powder and the second laser beam 43 has a weaker light intensity. Therefore, for example, when the beam splitter 120 divides the laser beam The first laser light 41 and the second laser light 43 may be divided into a predetermined division ratio such as 7: 3 or 8: 2.

The first laser light 41 is directed to the optical means 140 via the beam combiner 130. The optical means 140 may include a lens that adjusts the focus of the laser light to be irradiated on the object to be laminated (e.g., the specimen 20). Accordingly, the first laser light 41 can be irradiated with circular collimated light toward the object to be laminated after the focus is adjusted through the optical means 140.

The second laser beam 43 divided by the beam splitter 120 is directed to the optical device 170 through optical means such as mirrors 150 and 160. [ The optical device 170 makes the second laser light into a ring-shaped (or donut-shaped) light. To this end, in one embodiment, the optical device 170 may be implemented by an axicon lens, a light vortex phase plate, a galvano scanner, or the like, and may also generate ring-shaped laser light by a known technique.

The second laser beam 43 passing through the optical device 170 is coupled to the first laser beam 41 in the beam combiner 130. At this time, the first and second laser beams are aligned and combined with respect to one optical axis (45 in FIG. 3). The beam combiner 130 may be realized by a known optical means such as a prism or a dichroic lens.

The second laser beam 43 having passed through the beam combiner 130 is irradiated toward the object to be laminated after the focus is adjusted by the optical means 140. By the optical system structure as described above, The second laser light 43 can be irradiated on the surface of the object to be laminated in the form of a ring surrounding the first laser light.

8 shows an example of the optical system, and it goes without saying that additional optical means may be added on the optical path or a part of the existing optical means may be omitted. For example, optical means (e.g., a lens) for adjusting the focus of the second laser light 43 may be additionally provided at an arbitrary position between the optical device 170 and the laser light source 50 on the optical path of the second laser light Can be deployed. As an example, a further lens may be disposed between the optical device 170 and the mirror 160 and the lens may be adjusted (e.g., moving the lens back and forth over the optical path) to adjust the focus of the second laser light, It is possible to adjust the thickness of the ring shape (that is, the size of the ring-shaped outer peripheral radius and / or the inner radius).

9 is a view for explaining an optical system according to the second embodiment.

Referring to the drawings, an optical system according to the second embodiment may include a beam combiner 130, an optical device 170 that makes laser light into a ring shape, and a plurality of optical means 110, 140, and 180. Further, in the second embodiment, two laser light sources 50 and 70 can be used.

In one embodiment, the first laser light source 50 is a light source for generating the first laser light 41, and the optical means 110 is a collimating lens. Accordingly, the laser light generated by the first laser light source 50 can be collimated while passing through the optical means 110. The second laser light source 70 is a light source for generating the second laser light 43, and the optical means 180 may include a collimating lens. Accordingly, the laser light generated by the second laser light source 70 can be collimated light while passing through the optical means 180.

The optical means 110 and 180 may be omitted when the laser light generated and output from the laser light sources 50 and 70 is collimated light. As another example, it is needless to say that the optical means 110 and 180 can be omitted in the optical system even when it is not necessary to irradiate the collimated light to the object to be laminated.

The first laser beam 41 having passed through the optical means 110 is directed to the optical means 140 via the beam combiner 130. [ The optical means 140 may include a lens that adjusts the focus of the laser light to be irradiated on the object to be laminated (e.g., the specimen 20). Accordingly, the first laser light 41 can be irradiated with circular collimated light toward the object to be laminated after the focus is adjusted through the optical means 140.

The second laser light 43 passing through the optical means 180 is directed to the optical device 170. The optical device 170 makes the second laser light into a ring-shaped (or donut-shaped) light. In one embodiment, the optical device 170 may be implemented with an axicon lens, a light vortex phase plate, or a galvanometer scanner.

The second laser beam 43 passing through the optical device 170 is coupled to the first laser beam 41 in the beam combiner 130. At this time, the first and second laser beams are aligned and coupled based on one optical axis (45 in FIG. 3). The beam combiner 130 may be realized by a known optical means such as a prism or a dichroic lens.

The second laser beam 43 passed through the beam combiner 130 is irradiated toward the object to be laminated after the focus is adjusted by the optical means 140. With the optical system structure of FIG. 8 as described above, The second laser beam 43 may be irradiated in a ring shape surrounding the first laser beam on the surface of the object to be laminated.

Fig. 9 also shows an example of an optical system, in which additional optical means may be added on the optical path or part of the existing optical means may be omitted. For example, an optical means (for example, a lens) for adjusting the focus of the second laser light 43 is additionally provided at an arbitrary position between the optical device 170 and the laser light source 70 on the optical path of the second laser light . As an example, the thickness of the ring shape of the second laser light can be adjusted by further arranging a lens on the path before the second laser light reaches the optical means 180 and adjusting the lens. Alternatively, the thickness of the ring shape (that is, the size of the ring-shaped outer peripheral radius and / or the inner radius) may be adjusted while moving the optical means 180 back and forth on the optical path of the second laser light.

10 is a view for explaining an optical system according to the third embodiment.

The third embodiment of FIG. 10 shows a case of using an axicon lens 171 as the optical device 170 as a concrete example of the first embodiment of FIG. 8, the beam splitter 120, the beam combiner 130, and the plurality of optical means 110, 140, 150, and 160 correspond to the respective components of FIG. 8 and have the same or similar functions. It is omitted.

In the third embodiment shown in Fig. 10, the axicon lens 171 is a lens having a shape in which one surface of the lens is flat and the other surface is protruded toward the center of the lens, as shown in the figure. The second laser beam 43 having passed through the axicon lens 171 is deformed into a ring-shaped laser beam when it reaches the optical means 140 via the beam combiner 130 and arrives. At this time, optical means (for example, a lens) for adjusting the ring thickness of the second laser light 43 may be additionally provided as necessary.

(For example, between the axicon lens 171 and the mirror 160) between the axicon lens 171 and the laser light source 50 on the optical path of the second laser light, as an example, And the thickness of the ring shape of the second laser light (that is, the size of the outer diameter and / or the inner diameter of the ring shape) can be adjusted by disposing the lens and adjusting the lens.

The second laser beam 43 having passed through the axicon lens 171 is combined with the first laser beam 41 in the beam combiner 130 and is incident on the first and second 2 laser beams are aligned and combined. The first laser beam 41 and the second laser beam 43 having passed through the beam combiner 130 are simultaneously irradiated toward the object to be laminated. The second laser beam 43 is irradiated in a ring shape surrounding the first laser beam on the surface of the object to be laminated.

11 is a flowchart illustrating a laser light generating and irradiating method according to an embodiment.

Referring to FIG. 11, the laser light generating and irradiating method of the present invention will be described.

First, in step S110, the laser light generated by the laser light source is divided into a first laser light and a second laser light. 8, the laser light generated by the laser light source 50 is converted into the first laser light 41 and the second laser light 43 by the beam splitter 120. In this step S110, And a dividing step. In an alternative embodiment, in this step S110, the first laser light and the second laser light can be generated by separate laser light sources, respectively.

Next, in step S120, the second laser light is adjusted to ring-shaped light. In this step S120, for example, the second laser light 43 passes through the optical device 170 and can be deformed into ring-shaped light, which is transmitted through an axicon lens, , Or a galvanometer scanner or the like.

Thereafter, in step S130, the first laser light and the second laser light are aligned and coupled with respect to one optical axis. The step S130 may include aligning the optical axis by passing the first laser beam 41 and the second laser beam 43 through the beam combiner 130, for example.

Thereafter, in step S140, the first laser light and the second laser light aligned with respect to the optical axis are simultaneously irradiated onto the object to be laminated, so that the first laser light is irradiated onto the surface of the object to be laminated And at the same time, the second laser light can be irradiated on the surface of the object to be laminated in a ring shape surrounding the first laser light.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. As an example, the embodiment described above with reference to the drawings illustrates the DED (Directed Metal Deposition) method among the 3D printing methods. However, the present invention can be applied to other 3D printing methods, for example, a powder bed fusion (PBF) method. The PBF method is a method of forming a 3D laminate by repeatedly laying powder on a bed, melting a desired portion, and melting and melting another layer, wherein the first laser light for lamination and the second laser light for heating Technological configurations to investigate can be applied.

Also, in the above-described embodiment, a method and an apparatus for constructing a 3D laminate by using a first laser beam for stacking and a second laser beam for heating have been disclosed. However, The present invention can also be applied to a method of forming a sieve. That is, even when the electron beam is irradiated to the object to be laminated, the first electron beam for stacking and the second electron beam for surrounding the first electron beam and for heating the object to be laminated can be constituted.

8 to 10, optical systems such as optical means 110,140,180, beam splitter 120, beam combiner 130, and optical device 170, such as collimating lenses or optical lenses, And the like. However, it is to be understood that these embodiments are merely a conceptual illustration of the components constituting the embodiment of the present invention, and it is a matter of course that the specific shape and structure of each optical system may be changed in actual implementation of the apparatus.

Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims, as well as the appended claims.

10: Laser light output stage
20: The Psalms
30: cladding layer
40, 41,
45: optical axis
50, 70: laser light source
60: Powder feeder
100: Head unit
110: 140, 180: optical means
120: beam splitter
130: beam combiner
170: Optical device
171: Axicon lens
200: stage
300:

Claims (21)

1. A three-dimensional laser printing apparatus for melting a powder with laser light output from an optical system to laminate a clad layer,
The optical system comprising:
A first laser light (41) having a light intensity capable of melting the powder and irradiating the surface of the object to be laminated; And
And a second laser light (43) having a light intensity enough to heat the laminated clad layer without being remelted, and irradiating the surface of the object to be laminated in a shape surrounding the first laser light Characterized in that the three-dimensional laser printing device. The method according to claim 1,
The boundary portion of the irradiation region Ap of the first laser beam partially overlaps the inner boundary portion of the irradiation region Ah of the second laser beam by partially overlapping the first laser beam and the second laser beam A three-dimensional laser printing device. The method according to claim 1,
Characterized in that the first laser light is irradiated on the surface of the object to be laminated in a circular shape with a predetermined diameter and the second laser light is irradiated on the surface of the object to be laminated in a ring shape surrounding the first laser light , A three-dimensional laser printing device. The optical system according to claim 1,
A beam splitter for splitting the laser light generated from the laser light source into the first laser light and the second laser light; And
And a beam combiner for aligning and combining the first laser beam and the second laser beam with respect to one optical axis. The optical system according to claim 1,
A first laser light source for generating the first laser light;
A second laser light source for generating the second laser light; And
And a beam combiner for aligning and combining the first laser beam and the second laser beam with respect to one optical axis. 1. A three-dimensional laser printing apparatus for melting a powder with laser light output from an optical system to laminate a clad layer,
A beam splitter 120 for splitting the laser beam generated from the laser beam source into a first laser beam and a second laser beam;
An optical device (170) for shaping the second laser light to surround the first laser light; And
And a beam combiner (130) for aligning and combining the first laser light and the second laser light with respect to one optical axis,
Wherein the first laser light has a light intensity capable of melting powder and the second laser light has a light intensity enough to heat the laminated clad layer without re-melting. delete The method according to claim 6,
The boundary portion of the irradiation region Ap of the first laser beam partially overlaps the inner boundary portion of the irradiation region Ah of the second laser beam by partially overlapping the first laser beam and the second laser beam A three-dimensional laser printing device. The method according to claim 6,
Characterized in that the first laser light is irradiated on the surface of the object to be laminated in a circular shape with a predetermined diameter and the second laser light is irradiated on the surface of the object to be laminated in a ring shape surrounding the first laser light , A three-dimensional laser printing device. The method according to claim 6,
And an optical lens disposed between the optical device (170) and the laser light source on the optical path of the second laser light to adjust the thickness of the shape of the second laser light. Device. The method according to claim 6,
Characterized in that the optical device (170) comprises one of an axicon lens, a light vortex phase plate, and a galvanometer scanner. 1. A three-dimensional laser printing apparatus for melting a powder with laser light output from an optical system to laminate a clad layer,
A first laser light source (50) for generating a first laser light;
A second laser light source (70) for generating a second laser light;
An optical device (170) for shaping the second laser light to surround the first laser light; And
And a beam combiner (130) for aligning and combining the first laser light and the second laser light with respect to one optical axis,
Wherein the first laser light has a light intensity capable of melting powder and the second laser light has a light intensity enough to heat the laminated clad layer without re-melting. delete 13. The method of claim 12,
The boundary portion of the irradiation region Ap of the first laser beam partially overlaps the inner boundary portion of the irradiation region Ah of the second laser beam by partially overlapping the first laser beam and the second laser beam A three-dimensional laser printing device. 13. The method of claim 12,
Wherein the first laser light is irradiated on the surface of the object to be laminated in a circular shape with a predetermined diameter and the second laser light is irradiated on the surface of the object to be laminated in a ring shape surrounding the first laser light , A three-dimensional laser printing device. 13. The method of claim 12,
And an optical lens or collimating lens disposed between the optical device (170) and the second laser light source on the optical path of the second laser light,
And the thickness of the shape of the second laser light can be adjusted by moving the optical lens or the collimating lens back and forth on the optical path. 13. The method of claim 12,
Characterized in that the optical device (170) comprises one of an axicon lens, a light vortex phase plate, and a galvanometer scanner. A three-dimensional laser printing method for melting a powder with laser light output from an optical system to laminate a clad layer,
Dividing the laser light generated from the laser light source into a first laser light and a second laser light;
Adjusting the second laser light to light having a shape surrounding the first laser light;
Aligning the first laser light and the second laser light by aligning them with respect to one optical axis; And
And simultaneously irradiating the first and second laser beams onto the surface of the object to be laminated,
Wherein the first laser light has a light intensity capable of melting the powder and the second laser light has a light intensity enough to heat the laminated clad layer without re-melting. 19. The method of claim 18,
The boundary portion of the irradiation region Ap of the first laser beam partially overlaps the inner boundary portion of the irradiation region Ah of the second laser beam by partially overlapping the first laser beam and the second laser beam Dimensional laser printing method. A three-dimensional laser printing method for melting a powder with laser light output from an optical system to laminate a clad layer,
Generating a first laser beam and a second laser beam, respectively;
Adjusting the second laser light to light having a shape surrounding the first laser light;
Aligning the first laser light and the second laser light by aligning them with respect to one optical axis; And
And simultaneously irradiating the first and second laser beams onto the surface of the object to be laminated,
Wherein the first laser light has a light intensity capable of melting the powder and the second laser light has a light intensity enough to heat the laminated clad layer without re-melting. 21. The method of claim 20,
The boundary portion of the irradiation region Ap of the first laser beam partially overlaps the inner boundary portion of the irradiation region Ah of the second laser beam by partially overlapping the first laser beam and the second laser beam Dimensional laser printing method.

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