Dual-wavelength metal 3D printing optical path device and 3D printing system

Abstract

The application discloses a kind of dual-wavelength metal 3D printing optical path device and 3D printing system.The device includes first laser, second laser, first collimating unit, second collimating unit, dichroic mirror, galvanometer and field lens;The wavelength of the laser emitted by the first laser is greater than the wavelength of the laser emitted by the second laser;The first collimating unit, the dichroic mirror, the galvanometer and the field lens are arranged in the advancing direction of the laser emitted by the first laser in turn;The laser emitted by the second laser can reach the dichroic mirror through the second collimating unit;The dichroic mirror can make the spot of the laser emitted by the second laser surround the spot of the laser emitted by the first laser;The absorption rate of the metal to the laser emitted by the second laser is greater than the absorption rate to the laser emitted by the first laser.The system includes the device.The application can realize fine printing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of 3D printing, in particular to a dual-wavelength metal 3D printing optical path device and a 3D printing system. BACKGROUND

[0002] In the scene of 3D printing, the reflectivity of copper, aluminum, gold, silver and other metals to the 1μm laser generated by the conventional fiber laser is very high, which makes the effect of 3D printing very poor.

[0003] The disclosure of the above background art is only used to assist in understanding the inventive concept and technical solutions of the present application, and does not necessarily belong to the prior art of the present application. In the absence of explicit evidence that the above content has been disclosed before the filing date of the present application, the above background art should not be used to evaluate the novelty and inventiveness of the present application. SUMMARY

[0004] The present application provides a dual-wavelength metal 3D printing optical path device and a 3D printing system, which can realize fine printing and achieve better printing effect.

[0005] In a first aspect, the present application provides a dual-wavelength metal 3D printing optical path device for metal 3D printing, comprising a first laser, a second laser, a first collimating unit, a second collimating unit, a dichroic mirror, a galvanometer and a field lens.

[0006] The wavelength of the laser emitted by the first laser is greater than the wavelength of the laser emitted by the second laser;

[0007] The first collimating unit, the dichroic mirror, the galvanometer and the field lens are arranged in the forward direction of the laser emitted by the first laser in sequence;

[0008] The laser emitted by the second laser can pass through the second collimating unit to reach the dichroic mirror;

[0009] The dichroic mirror can make the spot of the laser emitted by the second laser surround the spot of the laser emitted by the first laser;

[0010] The absorption rate of the metal to the laser emitted by the second laser is greater than the absorption rate of the metal to the laser emitted by the first laser;

[0011] The laser emitted by the second laser is used to heat the metal, so that the absorption rate of the heated metal to the laser emitted by the first laser becomes larger;

[0012] The laser emitted by the first laser is used to melt the metal.

[0013] In some preferred embodiments, a mirror is further included.

[0014] The mirror is located between the second collimating unit and the dichroic mirror; or, the mirror is located between the first collimating unit and the dichroic mirror.

[0015] In some preferred embodiments, the dichroic mirror can make the laser emitted by the second laser coaxial with the laser emitted by the first laser.

[0016] In some preferred embodiments, the dichroic mirror can reflect the laser emitted by the first laser to the galvanometer; the laser emitted by the second laser can transmit the dichroic mirror to reach the galvanometer.

[0017] In some preferred embodiments, the dichroic mirror can reflect the laser emitted by the second laser to the galvanometer; the laser emitted by the first laser can transmit the dichroic mirror to reach the galvanometer.

[0018] In some preferred embodiments, the first laser is a fiber laser.

[0019] In some preferred embodiments, the wavelength of the laser emitted by the fiber laser is 1 μm.

[0020] In some preferred embodiments, the second laser is a blue laser semiconductor laser.

[0021] In some preferred embodiments, the first collimating unit and the second collimating unit are both collimating mirrors.

[0022] In some preferred embodiments, the metal includes at least one of copper, aluminum, gold and silver.

[0023] In a second aspect, the present application provides a 3D printing system comprising the above device.

[0024] Compared with the prior art, the beneficial effects of the embodiments of the present application include:

[0025] The dichroic mirror makes the spot of the laser emitted by the second laser surround the spot of the laser emitted by the first laser, and the laser passes through the galvanometer and the field lens, so that the area irradiated by the laser emitted by the second laser is larger, and the temperature of the metal is raised; the absorption rate of the heated metal to the laser emitted by the first laser increases with the increase of the temperature, so that the increase of the temperature of the metal can increase the absorption rate of the metal to the laser emitted by the first laser, and the laser emitted by the first laser can rapidly melt the metal, so that fine printing can be realized, and better printing effect can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1A structure schematic diagram of a dual-wavelength metal 3D printing optical path device of an embodiment of the present application;

[0027] Figure 2 A schematic diagram of a beam spot of a combined laser of an embodiment of the present application;

[0028] Figure 3 A structure schematic diagram of a variant of a dual-wavelength metal 3D printing optical path device of an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the technical problems to be solved by the embodiments of the present application, technical solutions and beneficial effects clearer, the following further describes the present application in conjunction with specific embodiments and examples. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application. Figures 1 to 3

[0030] It should be noted that when an element is referred to as being “fixed” or “disposed” on another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being “connected” to another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, the connection can be for fixing or for circuit communication.

[0031] It should be understood that the terms “length”, “width”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the embodiments of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0032] In addition, the terms “first”, “second” are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with “first”, “second” can explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of “a plurality of” is two or more, unless otherwise specifically limited.

[0033] The present embodiment provides a dual-wavelength metal 3D printing optical path device and a 3D printing system. The 3D printing system of the present embodiment includes the dual-wavelength metal 3D printing optical path device of the present embodiment.

[0034] ​The dual-wavelength metal 3D printing optical path device of the embodiment is used for 3D printing of metals, including but not limited to 3D printing of copper, aluminum, gold and silver, and specifically, 3D printing is realized by irradiating powdered metal with a laser.

[0035] Reference Figure 1 The dual-wavelength metal 3D printing optical path device of the embodiment includes a first laser 1, a second laser 2, a first collimating unit 3, a second collimating unit 4, a dichroic mirror 5, a galvanometer 6 (also referred to as a galvanometer system) and a field lens 7.

[0036] The wavelength of the laser emitted by the first laser 1 is greater than the wavelength of the laser emitted by the second laser 2.

[0037] In the embodiment, the first laser 1 is a fiber laser, and the wavelength of the laser emitted by the first laser 1 is 1 μm. The beam quality of the laser emitted by the first laser 1 is excellent, but the absorption rate of the metal to the laser emitted by the first laser 1 is low, such as the wavelength of the laser emitted by the first laser 1 being 1080 nm.

[0038] In the embodiment, the second laser 2 is a blue laser semiconductor laser (also referred to as a blue LD laser), which is a short-wavelength laser. The wavelength of the laser emitted by the blue laser semiconductor laser is less than 1 μm. The beam quality of the laser emitted by the second laser 2 is poor, such as the wavelength of the blue LD laser being 450 nm, but the absorption rate of the metal to the laser emitted by the second laser 2 is high.

[0039] In other embodiments, the specific forms of the first laser 1 and the second laser 2 can be determined according to actual conditions, as long as the purpose of the embodiment can be achieved.

[0040] In the embodiment, the first collimating unit 3 and the second collimating unit 4 are both collimating mirrors. In other embodiments, the specific forms of the first collimating unit 3 and the second collimating unit 4 can be determined according to actual conditions, as long as the purpose of the embodiment can be achieved.

[0041] Reference Figure 1 The first collimating unit 3, the dichroic mirror 5, the galvanometer 6 and the field lens 7 are arranged in sequence in the advancing direction 100 of the laser emitted by the first laser 1; wherein the advancing direction 100 can be tortuous. Reference Figure 1 In the advancing direction 100, the first collimating unit 3 is arranged behind the first laser 1, the dichroic mirror 5 is arranged behind the first collimating unit 3, the galvanometer 6 is arranged behind the dichroic mirror 5, and the field lens 7 is arranged behind the galvanometer 6. In this way, the laser emitted from the first laser 1 first reaches the first collimating unit 3, then the dichroic mirror 5, then the galvanometer 6, and then the field lens 7 after passing through the galvanometer 6.

[0042] Reference Figure 1The laser light emitted by the second laser 2 reaches the dichroic mirror 5 after passing through the second collimating unit 4. The second laser 2 shares the dichroic mirror 5, the galvanometer 6 and the field lens 7 with the first laser 1. In this way, the laser light emitted by the second laser 2 can also reach the galvanometer 6 and the field lens 7.

[0043] The dichroic mirror 5 can make the spot 20 of the laser light emitted by the second laser 2 surround the spot 10 of the laser light emitted by the first laser 1. Referring to Figure 2 , the spot 10 is located inside the spot 20. In the present embodiment, the dichroic mirror 5 is coaxial with the laser light emitted by the second laser 2 and the laser light emitted by the first laser 1, that is, the spot 10 is coaxial with the spot 20.

[0044] The dichroic mirror 5 can reflect one kind of laser light and transmit another kind of laser light. Referring to Figure 2 , in the present embodiment, the dichroic mirror 5 reflects the laser light emitted by the first laser 1 and transmits the laser light emitted by the second laser 2; in this way, the dichroic mirror 5 can reflect the laser light emitted by the first laser 1 to the galvanometer 6, and the laser light emitted by the second laser 2 transmits the dichroic mirror 5 to reach the galvanometer 6. Alternatively, referring to Figure 3 , the dichroic mirror 5 reflects the laser light emitted by the second laser 2 and transmits the laser light emitted by the first laser 1; in this way, the dichroic mirror 5 reflects the laser light emitted by the second laser 2 to the galvanometer 6, and the laser light emitted by the first laser 1 transmits the dichroic mirror 5 to reach the galvanometer 6.

[0045] Referring to Figure 1 , the dichroic mirror 5 is arranged at a first specified angle, for example, 45°, with the horizontal direction. A reflecting mirror 8 is arranged between the second collimating unit 4 and the dichroic mirror 5. The reflecting mirror 8 functions as a light path turning mirror, and reflects the laser light emitted from the second collimating unit 4 to the dichroic mirror 5. The second specified angle between the reflecting mirror 8 and the horizontal direction is equal to the first specified angle, so that the laser light emitted by the first laser 1 can be combined with the laser light emitted by the second laser 2 to form a combined laser beam 200 which propagates forward.

[0046] In other embodiments, the reflecting mirror 8 can be arranged between the first collimating unit 3 and the dichroic mirror 5, and reflects the laser light emitted from the first collimating unit 3 to the dichroic mirror 5.

[0047] In other embodiments, the reflecting mirror 8 is optional, for example, the second collimating unit 4 directly propagates the laser light to the dichroic mirror 5.

[0048] The metal of the present embodiment has a larger absorption rate for the laser light emitted by the first laser 1 as the temperature increases. In addition, the metal of the present embodiment has a larger absorption rate for the laser light emitted by the second laser 2 than for the laser light emitted by the first laser 1.

[0049] The laser emitted by the second laser 2 is used to heat the metal of the embodiment, but not to melt the metal of the embodiment. The laser emitted by the first laser 1 is used to melt the metal of the embodiment. The main function of the second laser 2 is to heat the material, i.e. the metal, so that the absorption rate of the laser, such as infrared light, emitted by the first laser 1 is increased after the metal is heated, so that the laser emitted by the first laser 1 is easily absorbed by the metal.

[0050] Reference Figure 1 The laser emitted by the first laser 1 is irradiated on the reflecting surface 51 of the dichroic mirror 5 after passing through the first collimating unit 3; the laser emitted by the second laser 2 is irradiated on the surface of the reflecting mirror 8, and is reflected by the reflecting mirror 8 to the transmitting surface 52 of the dichroic mirror 5; the two lasers are combined together after passing through the dichroic mirror 5 to form the combined laser 200, wherein the light spot 20 of the laser emitted by the second laser 2 surrounds the light spot 10 of the laser emitted by the first laser 1; the combined laser 200 is irradiated on the galvanometer 6, and then is irradiated on the field lens 7 to irradiate the metal on the scanning surface 300, so that the 3D printing is realized.

[0051] The reflectivity of the metal, such as copper, aluminum, gold, silver, etc. to the 1 μm laser generated by the conventional fiber laser (the first laser 1) is high, so that the effect of the 3D printing is poor; but the absorption rate of these metals to the short-wavelength laser is high, so that a better 3D printing effect can be obtained in theory. However, the short-wavelength laser, such as blue light LD (the second laser 2), is a multimode laser with poor beam quality, so that it is difficult to make fine printing.

[0052] Since the absorption rate of these metals changes with temperature, when the temperature of the metal is high, the absorption rate is also increased, so that the 1 μm laser generated by the fiber laser (the first laser 1) is easily absorbed by the metal. The embodiment utilizes the combined action of the dual-wavelength laser. The blue light multimode laser emitted by the blue light LD (the second laser 2) irradiates a large area, but does not melt the metal powder, only increases the temperature of the metal powder, and increases the absorption rate of the metal powder to the 1 μm wavelength laser generated by the fiber laser (the first laser 1), while the 1 μm laser generated by the fiber laser (the first laser 1) can rapidly melt the metal powder, so that fine printing can be realized, and a better printing effect is obtained.

[0053] The above description is further detailed description of the present application in combination with specific / preferred embodiments, and cannot be regarded as limitation of the specific implementation of the present application to these descriptions. For ordinary skilled in the art to which the present application belongs, without departing from the concept of the present application, some alternatives or modifications can be made to the described embodiments, and these alternatives or modifications shall be regarded as falling within the protection scope of the present application.

Claims

1. A dual wavelength metal 3D printing optical path arrangement for 3D printing of metal, characterized by: The device comprises a first laser, a second laser, a first collimating unit, a second collimating unit, a dichroic mirror, a galvanometer and a field lens. The first laser is a fiber laser, and the second laser is a blue laser semiconductor laser. The first collimating unit, the dichroic mirror, the galvanometer and the field lens are arranged in sequence in the direction of the laser emitted by the first laser. The laser emitted by the second laser can pass through the second collimating unit to reach the dichroic mirror. The dichroic mirror can reflect the laser emitted by the first laser to the galvanometer, and the laser emitted by the second laser can transmit the dichroic mirror to reach the galvanometer; or the dichroic mirror can reflect the laser emitted by the second laser to the galvanometer, and the laser emitted by the first laser can transmit the dichroic mirror to reach the galvanometer. The dichroic mirror can make the spot of the laser emitted by the second laser surround the spot of the laser emitted by the first laser. The absorption rate of the metal to the laser emitted by the second laser is greater than the absorption rate of the metal to the laser emitted by the first laser. The laser emitted by the second laser is used to heat the metal, so that the absorption rate of the heated metal to the laser emitted by the first laser increases with the increase of temperature. The laser emitted by the first laser is used to melt the metal after being heated.

2. The device according to claim 1, further comprising a mirror. The mirror is located between the second collimating unit and the dichroic mirror, or the mirror is located between the first collimating unit and the dichroic mirror. The dichroic mirror can make the laser emitted by the second laser coaxial with the laser emitted by the first laser.

3. The apparatus of claim 1, wherein: The wavelength of the laser emitted by the fiber laser is 1 μm.

4. The apparatus of claim 1, wherein: The first collimating unit and the second collimating unit are both collimating mirrors, and the metal comprises at least one of copper, aluminum, gold and silver.

5. The apparatus of claim 1, wherein: The device comprises the device according to any one of claims 1 to 5.

6. A 3D printing system characterized by: ​

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