WO2022053005A1

WO2022053005A1 - Double-beam slm forming device and method considering both forming efficiency and forming precision

Info

Publication number: WO2022053005A1
Application number: PCT/CN2021/117559
Authority: WO
Inventors: 魏恺文; 曾晓雁; 李祥友; 范有光
Original assignee: 华中科技大学
Priority date: 2020-09-14
Filing date: 2021-09-10
Publication date: 2022-03-17
Also published as: CN112091213A

Abstract

A double-beam SLM forming device, comprising a first laser source (1), a second laser source (2), a beam switching assembly, and a scanning processing assembly (3). The two laser sources are respectively used for outputting a medium/low power laser beam and a medium/high power laser beam. The beam switching assembly comprises a moving mechanism (7), and a first reflector (4) and a second reflector (5) arranged in a staggered manner. The two reflectors are driven by the moving mechanism to achieve position adjustment, and are respectively used for reflecting the collimated medium/low power laser beam and medium/high power laser beam to the scanning processing assembly (3). The scanning processing assembly is used for focusing the medium/low power laser beam or the medium/high power laser beam reflected by the beam switching assembly on the surface of a metal powder bed so as to complete SLM forming of metal parts. A double-beam SLM forming method is further involved. The device and method can solve the common problems in existing double-beam SLM equipment of low beam switching reliability, small forming size, and high manufacturing cost, and also achieve high-efficiency and high-precision SLM forming of metal parts.

Description

Dual-beam SLM forming device and method for both forming efficiency and forming accuracy

【Technical field】

The present invention belongs to the technical field of advanced manufacturing, and more particularly, relates to a double beam SLM forming device and method that takes both forming efficiency and forming accuracy into consideration.

【Background technique】

Selective Laser Melting (SLM) is one of the most promising high-performance metal additive manufacturing technologies. It achieves complex metal components by applying selective laser scanning melting and stacking to pre-laid metal powder layer by layer. the overall shape. However, the common SLM equipment on the market generally uses low-power lasers, and the forming efficiency is low (generally only 5-40 cm ³ /h), which cannot meet the needs of mass production. In order to solve this problem, domestic and foreign research institutions have recently proposed new SLM equipment based on dual-beam collaborative processing. This type of equipment is equipped with a low-power laser source and a high-power laser source at the same time. Realize the forming of metal parts.

For dual-beam SLM technology, how to achieve fast and reliable switching between low-power laser beams and high-power laser beams, taking into account the forming size and equipment cost, is the core problem that must be solved in the development of this technology. However, the existing dual-beam SLM equipment at home and abroad has not yet provided an ideal solution. For example, patent CN108580896A discloses a dual-beam SLM equipment including two sets of scanning galvanometer systems, wherein the two sets of galvanometers are installed in parallel above the forming cylinder and are respectively connected with a laser. This not only leads to high equipment cost, but also the double beam processing can only be carried out in the overlapping area of the scanning fields of the two sets of galvanometers, and the forming size is severely limited. Another example, patent CN103658647B discloses a laser selective melting equipment and processing method based on four laser dual-station, which can adjust the angle of the total reflection mirror, so that the high-power laser beam and the low-power laser beam alternately enter the same machine. Scanning galvanometer system, this technical solution has the advantages of low equipment cost and large forming size, but it requires extremely high rotation and positioning accuracy of the total reflection mirror, and it is difficult to realize fast and reliable switching of double beams. For another example, patents CN210098969U and CN104708003B propose a beam switching scheme based on a half mirror (spectroscope), so that two laser beams enter the same scanning galvanometer system through reflection and transmission of the half mirror respectively. This scheme does not involve the beam switching device. Rotational positioning, strong reliability. However, the cost of the half mirror is high, and it has special requirements on the wavelengths of the two laser beams, so it is not suitable for long-term operation of the high-power laser beam, which is not conducive to application and promotion.

In summary, it is of great significance to develop a dual-beam SLM equipment with fast beam switching speed, high reliability, large forming size, low manufacturing cost and strong applicability.

[Content of the invention]

In view of the above defects or improvement needs of the prior art, the present invention provides a dual-beam SLM shaping device and method that takes into account shaping efficiency and shaping accuracy, aiming to solve the common problems of existing dual-beam SLM equipment such as low beam switching reliability, low beam switching reliability, and low beam switching reliability. The problems of small forming size and high cost.

In order to achieve the above object, according to one aspect of the present invention, a dual-beam SLM forming device with both forming efficiency and forming accuracy is proposed, which includes a first laser source, a second laser source, a beam switching component and a scanning processing component, wherein :

The first laser source is used to output medium/low power laser beams to achieve high-precision SLM shaping, the second laser source is used to output medium/high power laser beams to achieve high-efficiency SLM shaping, the first laser source during the entire shaping process Working at the wrong time with the second laser source or only one of them;

The beam switching assembly includes a first reflector, a second reflector, and a motion mechanism. The first reflector and the second reflector are dislocated and can be adjusted in position under the drive of the motion mechanism, so as to ensure that the two work at different times. A reflector is used for reflecting the collimated medium/low power laser beam to the scanning processing assembly, and the second reflecting mirror is used for reflecting the collimated medium/high power laser beam to the scanning processing assembly;

The scanning processing component is used to focus the medium/low power laser beam or the medium/high power laser beam reflected by the beam switching component on the surface of the metal powder bed, so as to complete the high-precision and high-efficiency SLM forming of metal parts.

As a further preference, the first reflector and the second reflector are arranged on the reflector support in a staggered position. The reflector support is connected to the motion mechanism and slidably matched with the guide rail. The reflector support can be driven by the motion mechanism. The seat and the first reflecting mirror and the second reflecting mirror on it move along the guide rail.

As a further preference, the output power of the low-power laser beam is less than 500W, the output power of the medium-power laser beam is 500W-1000W, and the output power of the high-power laser beam is greater than 1000W.

As a further preference, the output power of the high-power laser beam is preferably greater than 1000W and less than or equal to 10000W, and more preferably 2000W to 6000W.

As a further preference, the scanning processing component is a combination of a two-axis scanning galvanometer and an F-Theta focusing mirror, or a dynamic focusing scanning galvanometer.

As a further preference, the angle between the mirror surface of the first reflector and the beam output path of the first laser source and the angle between the mirror surface and the beam input path of the scanning processing component are preferably designed to be 45°; The included angle between the mirror surface and the beam output path of the second laser source and the included angle between the mirror surface and the beam input path of the scanning processing component are preferably designed to be 45°.

As a further preference, the intersection of the beam output path of the first laser source and the beam input path of the scanning processing assembly is preferably located on a vertical line passing through the center of the mirror surface of the first mirror; preferably, the beam output path of the second laser source is the same as The point of intersection of the beam input paths of the scanning processing assembly is preferably located on a vertical line passing through the center of the mirror surface of the second mirror.

As a further preference, the motion mechanism is a linear drive mechanism.

As a further preference, the inside of the first reflector, the second reflector and the reflector support are all provided with a circulating cooling channel, and the cooling channel is connected to a liquid cooling device.

According to another aspect of the present invention, a dual-beam SLM forming method with both forming efficiency and forming accuracy is provided, which comprises the following steps:

S1 adjusts the mirror position according to the required laser beam:

If a medium/low power laser beam needs to be used, adjust the position of the first reflector through the motion mechanism, so that the intersection of the beam output path of the first laser source and the beam input path of the scanning processing component is located on the mirror surface of the first reflector, And go to step S2;

If a medium/high power laser beam needs to be used, the position of the second reflector is adjusted by the motion mechanism, so that the intersection of the beam output path of the second laser source and the beam input path of the scanning processing component is located on the mirror surface of the second reflector, And go to step S3;

S2 The first laser source emits a medium/low power laser beam after collimation, which is reflected by the first mirror to the scanning processing component, and focused on the surface of the metal powder bed to complete the high-precision SLM forming of metal parts;

The medium/high power laser beam emitted by the S3 second laser source is collimated, reflected by the second mirror into the scanning processing component, and focused on the surface of the metal powder bed to complete the high-efficiency SLM forming of metal parts.

In general, compared with the prior art, the above technical solutions conceived by the present invention mainly have the following technical advantages:

1. The switching of the medium/high power laser-medium/low power laser of the dual beam SLM forming device of the present invention can be realized by driving two sets of mirrors to move by the motion mechanism, and only one set of scanning processing components is included, and the manufacturing cost is low, Forming size is large.

2. The dual-beam SLM shaping device of the present invention has low requirements on the motion accuracy of the mirror, and only needs to ensure that the intersection of the output path of the laser source beam and the input path of the beam of the scanning processing component is located on the mirror surface of the mirror, and the processing requirements can be met, There is no need for the intersection of the two paths to completely coincide with the center of the mirror surface, enabling fast and reliable switching of the double beams.

3. The present invention realizes the indirect connection between the two mirrors and the moving mechanism through the mirror support, so that the adjustment of the positions of the two mirrors can be realized through the moving mechanism, thereby realizing the free switching of the two beams, and the two mirrors are dislocated. When one mirror is adjusted to the designated position, the other mirror will not interfere with it, ensuring the reliability of transmission.

4. The present invention uses a reflector as the transmission component of the laser beam, which is low in cost and has no special requirements for the laser wavelength. It is especially suitable for high-power laser beams, especially laser beams with a power of more than 2000W to work for a long time, which is conducive to application and promotion.

5. The forming device of the present invention has strong applicability and can provide laser beams of various powers to meet the high-efficiency and high-precision SLM forming of metal parts with different processing requirements.

【Description of drawings】

1 is a schematic structural diagram of a dual-beam SLM forming device that takes into account forming efficiency and forming accuracy provided by the present invention;

2 is a schematic diagram of the relative positions of the key components of the dual-beam SLM forming device with both forming efficiency and forming accuracy provided by the present invention, wherein (a) is a front view, and (b) is a top view;

3 is a schematic diagram of the relative positions of each key device when the dual-beam SLM forming device that takes into account forming efficiency and forming accuracy provided by the present invention adopts medium/low power laser beam forming;

4 is a schematic diagram of beam transmission when the dual-beam SLM forming device that takes into account forming efficiency and forming accuracy provided by the present invention adopts medium/low power laser beam forming;

5 is a schematic diagram of the relative positions of each key component when the dual-beam SLM forming device that takes into account forming efficiency and forming accuracy provided by the present invention adopts medium/high power laser beam forming;

FIG. 6 is a schematic diagram of beam transmission when the dual-beam SLM forming device that takes into account forming efficiency and forming accuracy provided by the present invention adopts medium/high power laser beam forming.

Throughout the drawings, the same reference numbers are used to refer to the same elements or structures, wherein:

1-first laser source; 2-second laser source; 3-scanning processing assembly; 4-first mirror; 5-second mirror; 6-mirror support; 7-movement mechanism; 8-guide rail; 11-beam output path of the first laser source; 21-beam output path of the second laser source; 31-beam input path of the scanning processing assembly; 40-the center of the mirror surface of the first mirror; 41-passing the mirror surface of the first mirror The vertical line in the center; 50—the center of the mirror surface of the second mirror; 51—the vertical line passing through the center of the mirror surface of the second mirror; 311—the intersection of the beam output path of the first laser source and the beam input path of the scanning processing assembly ; 321 - the intersection of the beam output path of the second laser source and the beam input path of the scanning processing assembly.

【detailed description】

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

As shown in FIG. 1 , an embodiment of the present invention provides a dual-beam SLM (Selective Laser Melting) forming device that takes both forming efficiency and forming accuracy into consideration, which includes a first laser source 1 , a second laser source 2 , a beam switching component and Scanning processing assembly 3, wherein, the first laser source 1 is used to output a medium/low power laser beam (medium power laser beam or low power laser beam), which is input to the scanning processing assembly through a mirror after collimation, so as to realize metal zero High-precision SLM shaping of parts (such as their precision parts or parts that require high-precision contours), the second laser source 2 is used to output a medium/high power laser beam (medium power laser beam or high power laser beam), collimated It is then input to the scanning processing assembly through the mirror to achieve high-efficiency SLM forming of metal parts (such as larger parts or parts with lower precision requirements). Specifically, the output power of the low-power laser beam is less than 500W, and the energy distribution is a Gaussian mode. The output power of the medium-power laser beam is 500W to 1000W, and the energy distribution can be Gaussian mode, flat-top mode, ring mode and various high-order modes. The output power of the high-power laser beam is greater than 1000W, preferably greater than 1000W and less than or equal to 10000W, more preferably 2000W-6000W, and the energy distribution can be Gaussian mode, flat top mode, ring mode and various high-order modes.

The beam switching assembly is used to realize the switching of the medium/low power beam and the medium/high power beam, which includes a first reflection mirror 4, a second reflection mirror 5 and a movement mechanism 7, and the first reflection mirror 4 is used to receive the first laser source 1 outputs the medium/low power laser beam, and transmits the received laser beam to the scanning processing component 3, and the second mirror 5 is used to receive the medium/high power laser beam output by the second laser source 2, and transmits the received laser beam The beam is delivered to the scanning processing assembly 3 . The first reflector 4 and the second reflector 5 are dislocated, for example, the second reflector 5 is located at the lower right of the first reflector 4 , and the first reflector 4 and the second reflector 5 can be driven up and down by the motion mechanism 7 Move, so that the two are adjusted to the required position and then receive the laser beam of corresponding power, that is, the first mirror 4 is adjusted to the working position to reflect the medium/low power laser beam to the scanning processing component, at this time the second reflection The mirror 5 does not work, or the second mirror 5 is adjusted to the working position to reflect the medium/high power laser beam into the scanning processing assembly. At this time, the first mirror 4 does not work, that is, the first mirror 4 and the second mirror The two mirrors 5 work at different times to ensure that only one type of laser beam is output from the scanning processing assembly 3 all the time.

The scanning processing component 3 is used to focus the medium/low power laser beam or the medium/high power laser beam reflected by the beam switching component on the surface of the metal powder bed to complete the high-precision and high-efficiency SLM forming of metal parts. Among them, the medium/high power laser beam can be used to process areas that do not have specific requirements for forming accuracy or allow subsequent machining, and can be processed by medium/high power lasers to achieve high-efficiency forming in this area. Medium/low power laser beams can be used to shape areas that are difficult to process with medium/high power lasers (such as areas with high precision requirements, areas where subsequent machining is not allowed, areas with wall thicknesses smaller than the spot diameter of the medium/high power laser beam, etc. ) to achieve high-precision shaping of this area.

In the SLM forming device of the present invention, in the whole forming process, the two laser sources (the first laser source 1 and the second laser source 2) work at the wrong time, that is, the two laser sources are put into use, but they are not working at the same time but at the wrong time. Alternate work; or only one of the two laser sources is put into use, for example, only the first laser source 1 works to provide a medium/low power laser beam to achieve high-precision forming of metal parts, and for example, only the second laser source 2 works , to provide medium/high power laser beams for high-efficiency forming of metal parts. Therefore, the forming device of the present invention can not only provide laser beams with medium/low power and medium/high power combination (ie low power + medium power, low power + high power, medium power + medium power, and medium power + high power), It is also possible to provide only low-power laser beams, medium-power laser beams or high-power laser beams, so as to greatly improve the applicability of the forming device of the present invention, which can be applied to any metal parts (such as complex structures, simple structures, high precision requirements, low Accuracy requirements, etc.) SLM forming, strong applicability and scalability.

Specifically, in order to ensure the reliability and stability of the adjustment, the first reflector 4 and the second reflector 5 are connected to the motion mechanism 7 through the reflector support 6, and the reflector support 6 is also slidably matched with the guide rail 8, that is, The first reflector 4 and the second reflector 5 are dislocated and arranged on the reflector support 6, and the reflector support 6 is connected with the motion mechanism 7, and the drive of the motion mechanism 7 can drive the reflector support 6 along the guide rail 8. It moves up and down, and then drives the first reflector 4 and the second reflector 5 on the reflector support 6 to move up and down together, so as to realize the adjustment of the upper and lower positions of the first reflector 4 and the second reflector 5 .

As mentioned above, the mirror is used to receive the laser beam output by the laser source and transmit the received laser beam to the scanning processing component, that is, the mirror can receive the laser beam from one component and transmit the received laser beam to another In order to realize the above functions, there must be a certain angle (that is, non-parallel) between the beam output path of the laser source and the beam input path of the scanning and processing assembly, that is, the mirror must be arranged obliquely, and the beam output path of the laser source must be The intersection point of the beam input path of the scanning processing unit needs to be located on the mirror surface of the mirror. That is, the mirror surface of the mirror and the beam output path of the laser source have a certain angle, and the beam output path of the laser source needs to intersect the mirror surface of the mirror, so that the laser beam of the laser source can be incident on the mirror surface of the mirror, and pass through the mirror. The specular surface of the mirror is reflected into the scanning processing component, and the specific angle can be set as required.

In order to facilitate the arrangement of the laser source, the scanning processing assembly and the mirror, the angle between the mirror surface of the mirror and the beam output path of the laser source is preferably 45°, and the angle between the mirror surface of the mirror and the beam input path of the scanning processing assembly is 45°, so that the beam output path of the laser source during processing is perpendicular to the beam input path of the scanning processing component, that is, the laser source, the mirror and the scanning processing component are arranged on the three vertices of the right triangle during processing, and the laser source during processing. The beam output path of the laser beam is perpendicular to the beam input path of the scanning processing component, so the design is convenient for the installation and arrangement of the three, avoiding mutual interference and influence during processing, and ensuring the quality of laser transmission. In order to ensure the effect of reflection and avoid the influence of the mirror on the reflected light source, the intersection of the beam output path of the laser source and the beam input path of the scanning processing assembly 3 is preferably located on a vertical line passing through the center of the mirror surface.

As shown in FIG. 2 , the angle between the mirror surface of the first reflecting mirror 4 and the beam output path 11 of the first laser source and the angle between the mirror surface and the beam input path 31 of the scanning processing component are both 45°. During scanning processing, the first The laser source 1 , the first reflecting mirror 4 and the scanning processing assembly 3 are arranged on three vertices of a right triangle, and the beam output path of the first laser source 1 is perpendicular to the beam input path of the scanning processing assembly 3 . The angle between the mirror surface of the second mirror 5 and the beam output path 21 of the second laser source and the angle between the mirror surface and the beam input path 31 of the scanning processing component are both 45°. The mirror 5 and the scanning processing assembly 3 are arranged on three vertices of a right triangle, and the beam output path of the second laser source 2 is perpendicular to the beam input path of the scanning processing assembly 3 . The intersection 311 of the beam output path 11 of the first laser source and the beam input path 31 of the scanning processing assembly is located on a vertical line 41 passing through the center 40 of the mirror surface of the first mirror. The beam output path 21 of the second laser source and the scanning processing assembly The intersection point 321 of the beam input path 31 of , is located on the vertical line 51 passing through the center 50 of the mirror surface of the second mirror.

Further, the motion mechanism 7 is a linear drive mechanism, preferably an electric cylinder or cylinder with lower cost, higher movement speed and smaller size. Since the device of the present invention does not require high movement accuracy, an electric cylinder or cylinder is used. to meet the needs. In order to facilitate the cooling and cooling of the reflector, improve its service life and ensure the accuracy of use, the first reflector 4, the second reflector 5 and the reflector support 6 are provided with a circulating cooling channel, which is connected to a liquid cooling device. . More specifically, the forming device of the present invention performs SLM forming in the form of galvanometer scanning, and the matching scanning processing component 3 is a combination of a two-axis scanning galvanometer and an F-Theta focusing mirror, or a dynamic focusing scanning galvanometer.

The present invention also provides a dual-beam SLM shaping method that takes both shaping efficiency and shaping accuracy into consideration, which adopts the above-mentioned dual-beam SLM shaping device, and specifically includes the following steps:

S1 First, adjust the mirror position according to the laser beam to be used:

If it is necessary to use a medium/low power laser beam (for example, areas where it is difficult to use medium/high power laser processing, such as areas with extremely high precision requirements, areas where subsequent machining is not allowed, and those with a wall thickness smaller than the spot diameter of the medium/high power laser beam) area, generally need to use a medium/low power laser beam to ensure the forming accuracy), then adjust the position of the first mirror 4 through the motion mechanism 7, so that the beam output path of the first laser source 1 and the beam input path of the scanning processing component The intersection point is located on the mirror surface of the first reflecting mirror 4, and goes to step S2;

If a medium/high power laser beam needs to be used (there is no specific requirement for the forming accuracy or the area that allows subsequent machining is generally a medium/high power laser beam to ensure the forming efficiency), the movement mechanism 7 is used to adjust the second mirror 5. position, so that the intersection of the beam output path of the second laser source 2 and the beam input path of the scanning processing assembly is located on the mirror surface of the second reflector 5, and the process goes to step S3;

S2 The first laser source 1 emits a medium/low power laser beam, and the laser beam is collimated and reflected by the first mirror 4 into the scanning processing component, and focused on the surface of the metal powder bed to complete the high precision of the corresponding area of the metal parts SLM forming;

S3 The second laser source 2 emits a medium/high power laser beam, the laser beam is collimated and then reflected by the second mirror 5 into the scanning processing component, and focused on the surface of the metal powder bed to complete the high efficiency of the corresponding area of the metal parts SLM takes shape. Specifically, for high-efficiency SLM forming, multiple thin-layer powder layers can be superimposed and then scanned and formed at the same time, that is, multiple layers of metal powder can be laid. This further improves the forming efficiency.

The following are specific examples:

Example 1

This embodiment takes the nickel-based superalloy aviation rocker bracket as an example to illustrate the dual-beam SLM forming method of the present invention, which specifically includes the following steps:

S1 first determines the type of laser beam used to shape the different areas of the part:

The part is composed of a base and a cantilever; among them, the base has a simple shape, low precision requirements, and allows subsequent machining, so high-power laser beam forming is used; the cantilever has a complex structure, high precision requirements, and it is difficult to use high-power laser beam forming. , so the medium power laser beam shaping is used;

S2 slices the 3D model of the part to generate N slice layers (N≥2);

S3 Shape the cantilever part contained in the first slice layer of the part: adjust the mirror surface center 40 of the first mirror 4 to the beam output path 11 of the first laser source and the beam input path 31 of the scanning processing assembly through the motion mechanism 7 The intersection point 311 of the laser beam is basically coincident, as shown in Figure 3, and the transmission of the laser beam at this time is shown in Figure 4;

S4 The first laser source 1 emits a laser beam with a power of 800W, after collimated, is reflected by the first mirror 4 into the scanning processing component, and focused on the surface of the metal powder bed, so as to complete the height of the cantilever part contained in the first slicing layer. Precision forming;

S5 Shape the base part contained in the first slice layer of the part: adjust the mirror surface center 50 of the second mirror 5 to the beam output path 21 of the second laser source and the beam input path of the scanning processing assembly through the motion mechanism 7 The intersection point 321 of 31 is basically coincident, as shown in Figure 5, and the transmission of the laser beam at this time is shown in Figure 6;

S6 The second laser source 2 emits a 4000W laser beam after collimated, and then reflected by the second mirror 5 into the scanning processing component, and focused on the surface of the metal powder bed to complete the base part contained in the first slicing layer high-efficiency forming;

S7 completes the processing of the subsequent N-1 slice layers according to S3-S6, and realizes the high-efficiency and high-precision SLM forming of the nickel-based superalloy aviation rocker bracket.

Example 2

This embodiment takes a titanium alloy gas turbine stator blade as an example to illustrate the dual beam SLM forming method of the present invention, which specifically includes the following steps:

The part consists of a base and a blade body. Among them, the base has a simple shape, low precision requirements, and allows subsequent machining, so a high-power laser beam is used for forming; the blade body has a complex structure and high precision requirements, making it difficult to use high-power lasers Beam shaping, so use low-power laser beam shaping;

S2 slices the 3D model of the part to generate N slice layers (N≥2);

S3 Shape the blade body part contained in the first slice layer of the part: adjust the mirror surface center 40 of the first mirror 4 to the beam output path 11 of the first laser source and the beam input of the scanning processing component through the motion mechanism 7 The intersection 311 of the path 31 basically coincides, as shown in FIG. 3 , and the transmission of the laser beam at this time is shown in FIG. 4 ;

S4 The laser beam with the emission power of 300W from the first laser source 1 is collimated, then reflected by the first mirror 4 into the scanning processing component, and focused on the surface of the metal powder bed to complete the blade body contained in the first slicing layer High-precision forming of parts;

S6 The laser beam with the emission power of 6000W emitted by the second laser source 2 is collimated, then reflected by the second mirror 5 into the scanning processing component, and focused on the surface of the metal powder bed to complete the susceptor contained in the first slicing layer High-efficiency forming of parts;

S7 completes the processing of subsequent N-1 slice layers according to S3-S6, and realizes high-efficiency and high-precision SLM forming of titanium alloy gas turbine stator blades.

Example 3

In this embodiment, a magnesium alloy biological stent is used as an example to illustrate the dual-beam SLM forming method of the present invention, which specifically includes the following steps:

S1 determines the laser beam to be used: due to the complex structure of the magnesium alloy bioscaffold, it is difficult to use high-power laser beam shaping, so all parts of it are shaped by low-power laser beam;

S2 adjusts the mirror surface center 40 of the first reflecting mirror 4 to be substantially coincident with the intersection 311 of the beam output path 11 of the first laser source and the beam input path 31 of the scanning processing assembly through the motion mechanism 7 , as shown in FIG. 3 , at this time The transmission of the laser beam is shown in Figure 4;

S3 The first laser source 1 emits a laser beam with a power of 180W, which is collimated and reflected by the first mirror 4 into the scanning processing component, and focused on the surface of the metal powder bed to complete the high-precision forming of the magnesium alloy bioscaffold.

Example 4

This embodiment takes a stainless steel support beam as an example to illustrate the dual beam SLM forming method of the present invention, which specifically includes the following steps:

S1 determines the laser beam to be used. Due to the simple shape of the stainless steel support beam, all parts can be formed by high-power laser beams, and the accuracy requirements are low, allowing subsequent machining, so all parts are formed by high-power laser beams;

S2 adjusts the mirror surface center 50 of the second mirror 5 through the motion mechanism 7 to substantially coincide with the intersection 321 of the beam output path 21 of the second laser source and the beam input path 31 of the scanning processing assembly, as shown in FIG. 5 , at this time The transmission of the laser beam is shown in Figure 6;

S5 The second laser source 2 emits a laser beam with a power of 5500W, which is reflected by the second mirror 5 into the scanning processing component after collimation, and focused on the surface of the metal powder bed to complete the high-efficiency forming of the stainless steel bracket.

Example 5

In this embodiment, the air intake port of a nickel-based superalloy aircraft engine is taken as an example to illustrate the dual-beam SLM forming method of the present invention, which specifically includes the following steps:

The part consists of a base and an air inlet; among them, the base has a simple shape, low precision requirements, and allows subsequent machining, so a medium-power laser beam is used for forming; the air inlet has a complex structure, high precision requirements, and is difficult to use. / High-power laser beam shaping, so use low-power laser beam shaping;

S2 slices the 3D model of the part to generate N slice layers (N≥2);

S3 Shape the air inlet part contained in the first slice layer of the part: adjust the mirror surface center 40 of the first mirror 4 to the beam output path 11 of the first laser source and the beam input of the scanning processing component through the motion mechanism 7 The intersection 311 of the path 31 basically coincides, as shown in FIG. 3 , and the transmission of the laser beam at this time is shown in FIG. 4 ;

S4 The first laser source 1 emits a 400W laser beam after collimated, reflected by the first mirror 4 into the scanning processing component, and focused on the surface of the metal powder bed to complete the part of the air inlet contained in the first slicing layer high-precision forming;

S5 Shape the base part contained in the first slice layer of the part: adjust the mirror surface center 50 of the second mirror 5 to the beam output path 21 of the second laser source and the beam input path of the scanning processing assembly through the motion mechanism 7 The intersection point 321 of 31 basically coincides, as shown in Figure 5, and the transmission of the laser beam at this time is shown in Figure 6;

S6 The second laser source 2 emits a 900W laser beam after collimated, and then reflected by the second mirror 5 into the scanning processing component, and focused on the surface of the metal powder bed to complete the base part contained in the first slice layer high-efficiency forming;

S7 completes the processing of the subsequent N-1 slice layers according to S3-S6, and realizes the high-efficiency and high-precision SLM forming of the intake port of the nickel-based superalloy aircraft engine.

Example 6

In this embodiment, the copper alloy conductive shell is taken as an example to describe the dual beam SLM forming method of the present invention, which specifically includes the following steps:

The part is composed of a base and a curved surface of the shell; among them, the shape of the base is simple, the precision requirements are low, and subsequent machining is allowed, so a medium-power laser beam is used for forming; the surface of the shell has a complex structure and high precision requirements, and it is difficult to use high-power lasers Beam forming, but can use medium power laser beam forming, so use medium power laser beam forming;

S2 slices the 3D model of the part to generate N slice layers (N≥2);

S3 Shape the curved surface part of the shell contained in the first slice layer of the part: adjust the mirror surface center 40 of the first mirror 4 to the beam output path 11 of the first laser source and the beam input of the scanning processing component through the motion mechanism 7 The intersection 311 of the path 31 basically coincides, as shown in FIG. 3 , and the transmission of the laser beam at this time is shown in FIG. 4 ;

S4 The first laser source 1 emits a 600W laser beam after collimated, reflected by the first mirror 4 into the scanning processing component, and focused on the surface of the metal powder bed to complete the curved surface part of the shell contained in the first slice layer high-precision forming;

S5 Shape the base part contained in the first slice layer of the part: adjust the mirror surface center 50 of the second mirror 5 to the beam output path 21 of the second laser source and the beam input path 31 of the scanning processing assembly through the motion mechanism 7 The intersection point 321 of the laser beam is basically coincident, as shown in FIG. 5 , and the transmission of the laser beam at this time is shown in FIG. 6 ;

S6 The second laser source 2 emits a laser beam with a power of 850W after collimation, and is then reflected by the second mirror 5 into the scanning processing component, and focused on the surface of the metal powder bed, so as to complete the laser beam of the base part contained in the first slicing layer. High-efficiency forming;

S7 completes the processing of the subsequent N-1 slice layers according to S3-S6, and realizes the high-efficiency and high-precision SLM forming of the copper alloy conductive shell.

Example 7

This embodiment takes the CoCr alloy artificial spine as an example to illustrate the dual-beam SLM forming method of the present invention, which specifically includes the following steps:

S1 determines the laser beam to be used: The structure of the CoCr alloy artificial spine is complex, and it is difficult to use a high-power laser beam to form, but it can be formed by a medium-power laser beam, so all its parts are formed by a medium-power laser beam;

S3 The first laser source 1 emits a laser beam with a power of 600W, which is reflected by the first mirror 4 into the scanning processing component after collimation, and focused on the surface of the metal powder bed to complete the high-precision forming of the CoCr alloy artificial spine.

The dual-beam SLM forming device of the present invention can solve the problems of low beam switching reliability, small forming size and high manufacturing cost commonly existing in the existing dual-beam SLM equipment, realize high-efficiency and high-precision SLM forming of metal parts, and the device structure is simple , can be realized by transforming the existing SLM equipment, with strong expansibility, and can be combined with "two-way powder spreading" (CN104001915A), "recombinable forming cylinder" (CN104668563A), "conformal cylinder" (CN106346006A), "multi-region parallel processing (CN104668563A)" CN102266942A)" and other technologies are combined to better realize the improvement of forming efficiency, precision, size and reduction of manufacturing cost.

Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, etc., All should be included within the protection scope of the present invention.

Claims

A dual-beam SLM forming device that takes both forming efficiency and forming accuracy into consideration, characterized in that it comprises a first laser source (1), a second laser source (2), a beam switching component and a scanning processing component (3), wherein:

The first laser source (1) is used for outputting medium/low power laser beams to achieve high-precision SLM shaping, and the second laser source (2) is used for outputting medium/high power laser beams to achieve high-efficiency SLM forming, during the whole forming process, the first laser source (1) and the second laser source (2) work at staggered time or only one of them works;

The light beam switching assembly includes a first reflection mirror (4), a second reflection mirror (5) and a movement mechanism (7), the first reflection mirror (4) and the second reflection mirror (5) are dislocated and can be The position adjustment is realized under the driving of the motion mechanism (7) to ensure that the two work at different times, wherein the first mirror (4) is used to reflect the collimated medium/low power laser beam to the the scanning processing assembly (3), the second mirror (5) is used for reflecting the collimated medium/high power laser beam to the scanning processing assembly (3);

The scanning processing component (3) is used for focusing the medium/low power laser beam or the medium/high power laser beam reflected by the beam switching component on the surface of the metal powder bed, so as to complete the high precision and high efficiency of the metal parts SLM shaping.
The double-beam SLM forming device taking into account both forming efficiency and forming accuracy according to claim 1, characterized in that, the first reflecting mirror (4) and the second reflecting mirror (5) are arranged in a staggered position on the reflecting mirror support (6). ), the mirror support (6) is connected with the moving mechanism (7), and is slidingly matched with the guide rail (8), and the mirror support (6) can be driven by the driving of the moving mechanism (7). and the first reflecting mirror (4) and the second reflecting mirror (5) thereon move along the guide rail (8).
The dual-beam SLM shaping device according to claim 1, wherein the output power of the low-power laser beam is less than 500W, the output power of the medium-power laser beam is 500W-1000W, and the output power of the high-power laser beam is 500W-1000W. The output power of the laser beam is greater than 1000W.
The dual-beam SLM forming apparatus of claim 3, wherein the output power of the high-power laser beam is preferably greater than 1000W and less than or equal to 10000W, more preferably 2000W-6000W.
The dual-beam SLM forming device with both forming efficiency and forming accuracy as claimed in claim 1, wherein the scanning processing component is a combination of a two-axis scanning galvanometer and an F-Theta focusing mirror, or a dynamic focusing scanning oscillating mirror. mirror.
The dual-beam SLM shaping device according to any one of claims 1 to 5, characterized in that the mirror surface of the first reflecting mirror (4) and the first laser source (1) The included angle of the beam output path and the included angle of the beam input path of the scanning processing assembly are preferably designed to be 45°; preferably, the mirror surface of the second reflector (5) and the second laser source (2) The included angle of the beam output path and the included angle with the beam input path of the scanning processing component are preferably designed to be 45°.
The dual-beam SLM forming device taking into account forming efficiency and forming accuracy according to any one of claims 1-6, characterized in that the beam output path of the first laser source (1) is the same as the beam output path of the scanning processing assembly (3). The intersection point of the beam input path is preferably located on a vertical line passing through the center of the mirror surface of the first reflector (4); preferably, the beam output path of the second laser source (2) and the beam input path of the scanning processing assembly (3) The intersection point of is preferably located on a vertical line passing through the center of the mirror surface of the second mirror (5).
The double-beam SLM forming device according to any one of claims 1-7, characterized in that, the motion mechanism (7) is a linear drive mechanism.
The double-beam SLM shaping device with both shaping efficiency and shaping accuracy according to any one of claims 1-8, characterized in that the first reflecting mirror (4), the second reflecting mirror (5) and the reflecting mirror support The inside of the seat (6) is provided with a circulating cooling channel, and the cooling channel is connected to a liquid cooling device.
A dual-beam SLM forming method that takes both forming efficiency and forming accuracy into consideration, is characterized in that, it comprises the following steps:

S1 adjusts the mirror position according to the required laser beam:

If a medium/low power laser beam needs to be used, the position of the first mirror (4) is adjusted by the motion mechanism (7) so that the beam output path of the first laser source (1) and the beam input path of the scanning processing component intersect at the point of intersection. be located on the mirror surface of the first reflecting mirror (4), and go to step S2;

If a medium/high power laser beam needs to be used, the position of the second mirror (5) is adjusted by the moving mechanism (7) so that the beam output path of the second laser source (2) and the beam input path of the scanning processing component intersect at the point of intersection. be located on the mirror surface of the second reflecting mirror (5), and go to step S3;

S2, the first laser source (1) emits a medium/low power laser beam, the laser beam is collimated and reflected by the first mirror (4) into the scanning processing assembly (3), and focused on the surface of the metal powder bed, Complete high-precision SLM forming of metal parts;

S3 the second laser source (2) emits a medium/high power laser beam, the laser beam is collimated and reflected by the second mirror (5) into the scanning processing assembly (3), and focused on the surface of the metal powder bed, Complete high-efficiency SLM forming of metal parts.