CN210098969U

CN210098969U - SLM high-power part forming device

Info

Publication number: CN210098969U
Application number: CN201822201888.1U
Authority: CN
Inventors: 杨东辉; 赵彪
Original assignee: Xian Bright Laser Technologies Co Ltd
Current assignee: Xian Bright Laser Technologies Co Ltd
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2020-02-21
Anticipated expiration: 2028-12-26

Abstract

The utility model discloses a SLM high-power part forming device, which comprises a laser beam combiner, a dynamic focusing device and a scanning galvanometer which are arranged in sequence; the laser beam combiner comprises a high-power laser, a high-power pulse laser and a laser conversion device, wherein the laser conversion device is used for realizing the alternate use of the high-power laser and the high-power pulse laser. The utility model discloses a laser beam focus mode of preceding focus galvanometer for the facula is the same on every point of whole machined surface, has improved the precision that the part printed. In the processing process, two kinds of laser are used alternately, so that the high-efficiency forming of parts is guaranteed, the surface precision and roughness of the parts can be guaranteed, and the processing cost of the parts is reduced.

Description

SLM high-power part forming device

Technical Field

The utility model belongs to the technical field of the vibration material disk, concretely relates to high-power part forming device of SLM.

Background

The laser focusing mode includes a front focusing galvanometer (PRE-SCAN) mode and a rear focusing galvanometer (POST-SCAN) mode, wherein the POST-SCAN mode focuses after scanning, and the PRE-SCAN mode focuses before scanning. Currently, the most common mode used by the SLM is a rear focusing galvanometer mode, i.e., a laser beam emitted by a laser firstly passes through a collimating lens and a beam expanding lens, then passes through a scanning galvanometer, and finally passes through a field lens (also called f-theta lens and f-theta field lens) to be scanned to a processing surface. The scanning galvanometer realizes the deflection of the laser beam by changing the reflection angles of the two reflection mirrors in the direction of the X, Y axis, thereby controlling the laser beam to move according to a specified scanning path. The f-theta lens changes the position of the imaging light beam on the premise of not changing the optical characteristics of the optical system, and realizes uniform light spot focusing on the whole processing surface.

The SLM adopts a laser beam focusing mode of a rear focusing galvanometer, the scanning area is limited by an f-theta lens, and the size of each light spot in a scanning plane is different. When the scanning range of the field lens is enlarged, the working distance is inevitably increased, the diameter of the obtained light spot is enlarged, namely the light spot is not converged thin enough, the power density of the laser is reduced very fast (the power density is inversely proportional to the 2-power of the diameter of the light spot), and the energy loss is increased. Since the f-theta field lens operates using the relationship y' f theta and the actual values of theta and tg theta are different, the spot distortion will be larger as the focal length f is larger. Therefore, the SLM cannot realize high-precision machining forming of large-size parts, and the machining breadth of the general SLM can only be below 1m at present.

The SLM laser beam depends on the energy absorption of materials, the laser power is low, the peak intensity of the laser is low, so that the printing of parts needs long time, the processing efficiency is low, the particle size of processed material powder is small, and the production cost is increased. The surface quality of the SLM processing parts cannot meet the requirements, and a plurality of post-treatments are needed to finish the surfaces of the parts, which undoubtedly increases the processing cost of the parts.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a high-power part forming device of SLM has solved current SLM processing part, and machining efficiency is low, and part surface is coarse, problem that manufacturing cost is high.

The technical scheme adopted by the utility model is that the SLM high-power part forming device comprises a laser beam combiner, a dynamic focusing device and a scanning galvanometer which are arranged in sequence;

the laser beam combiner comprises a high-power laser, a high-power pulse laser and a laser conversion device, wherein the laser conversion device is used for realizing the alternate use of the high-power laser and the high-power pulse laser.

The utility model is also characterized in that,

wherein the laser conversion device is a reflector or a semi-transparent mirror.

Wherein the mirror is rotatable.

The reflecting mirror is connected with a servo motor, and the reflecting mirror is driven to rotate by the servo motor.

Wherein the semi-transparent mirror is arranged at an angle of 45 DEG with the laser path.

Wherein the high-power laser and the high-power pulse laser are arranged vertically.

The utility model has the advantages that,

1. the utility model discloses a laser beam focus mode of preceding focus galvanometer (PRE-SCAN) for the facula is the same on every point of whole machined surface, has improved the precision that the part printed. The dynamic focusing can prolong the focal length, the scanning range of the laser is enlarged, the breadth size of the printed part is increased, and meanwhile, the high-precision forming of parts with larger sizes can be completed by splicing a plurality of vibrating mirrors.

2. In the processing process, two kinds of laser are used alternately, so that the high-efficiency forming of parts is guaranteed, the surface precision and roughness of the parts can be guaranteed, and the processing cost of the parts is reduced.

3. The high-power laser is adopted, the material is rapidly melted and bonded and formed without depending on the energy absorption of the material, the forming efficiency of parts is favorably improved, and the metal powder with large granularity can be used, and the large-particle metal powder is relatively cheap, so that the production cost is reduced.

Drawings

FIG. 1 is a schematic structural view of an embodiment of the apparatus of the present invention;

FIG. 2 is a schematic structural diagram of another embodiment of the apparatus of the present invention;

FIG. 3 is a process flow diagram of one embodiment of the apparatus of the present invention;

FIG. 4 is a schematic view of a printing state of a part according to an embodiment of the present invention;

FIG. 5 is a schematic view of a surface treatment state of a part according to an embodiment of the present invention;

FIG. 6 is a process flow diagram of another embodiment of the apparatus of the present invention;

FIG. 7 is a schematic view of a printing position of a part of another embodiment of the apparatus of the present invention;

fig. 8 is a schematic view of a surface treatment state of a part according to another embodiment of the apparatus of the present invention.

In the figure, 1 is a high-power laser, 2 is a high-power pulse laser, 3 is a dynamic focusing device, 4 is a scanning vibrating mirror, 5 is a substrate, 6 is a laser conversion device, 7 is a reflector, 8 is a reflector rotating direction, and 9 is a semi-transparent mirror.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

The utility model relates to a high-power part forming device of SLM, including laser beam combiner, dynamic focusing device and the scanning mirror that shakes that sets gradually.

The laser beam combiner comprises a high power laser 1, a high power pulse laser 2 and a laser conversion device 6.

The laser conversion device is used for realizing the alternate use of the high-power laser 1 and the high-power pulse laser 2. The laser conversion device shown in fig. 1 and 2 is a rotatable reflector or a 45-degree semi-transparent mirror.

The reflecting mirror 7 is connected with a servo motor, and the reflecting mirror 7 is driven by the servo motor to rotate by a certain angle.

The high-power laser 1 and the high-power pulse laser 2 are arranged in positions, so that the emitted laser can enter the phase dynamic focusing device in parallel along with the conversion of the laser conversion device. Such as being disposed perpendicular to each other.

The utility model discloses a preceding focus shakes mirror (PRE-SCAN) laser beam focus mode, uses two kinds of laser of high power laser instrument and high power pulse laser, has designed a new light beam combiner, and two kinds of laser exchange use same scanning head in real time, divides the work to accomplish the shaping vibration material disk process of part and part surface treatment subtract the material process. The front focusing galvanometer adopts a long-focusing dynamic focusing device before scanning the galvanometer, when light spots output by a laser are focused by the dynamic focusing lens, the focusing focal length is larger than the distance from the dynamic focusing lens to the galvanometer, namely scanning is carried out in the light beam focusing process, and the focal length of the focusing lens is changed according to the distance from each point of a workpiece plane to the focusing lens, so that all focused light spots are focused on the plane where the workpiece is positioned, and the focused light spots on the whole breadth are uniformly distributed.

The dynamic focusing is a technology developed for the deviation problem of ordinary focusing, and it adopts a regulator to periodically generate focusing voltage with special waveform, so that the voltage of electron beam is lowest at central point, and the voltage is gradually increased along with the increase of focal length when the corner is scanned, and the focusing change can be corrected at any time.

High power lasers have high peak intensities resulting in rapid energy transfer to the material independent of the absorption by the material, which facilitates rapid additive forming of the material. High-power pulse laser is widely used for texture carving, rapid gasification and finishing of material surfaces.

The high-power laser and the high-power pulse laser are alternately used by utilizing a rotatable reflector or a 45-degree semi-transparent mirror, the size of a focusing light spot of laser emitted by a high-power laser on the surface of the whole part and the energy density of the large light spot can be adjusted in real time through dynamic focusing, the melting and solidification of metal powder are realized, and finally, the part processing (SLM principle) is realized according to a set path; the dynamic focusing can adjust the size of a focusing spot of laser emitted by a high-power pulse laser on the surface of a part in real time, and the small spot has high energy density, thereby realizing the purposes of polishing, gasifying and finishing the surface of the part. The composite processing ensures high-efficiency forming and also ensures the precision and the roughness of the surface of the part. The utility model discloses can realize that the high accuracy of SLM jumbo size part takes shape.

The reflector realizes total reflection of the laser.

A half mirror is a special mirror that can transmit one light and reflect another. The mirror surface is coated with a light splitting film, and the principle is the interference effect of light rays, so that light with certain wavelength is allowed to transmit and light with certain wavelength is reflected. The utility model discloses a semi-transparent mirror can see through high power laser, reflects high power pulse laser.

By using dynamic focusing, a laser combiner, and a high power laser, the SLM can process parts of large size, high precision, and good surface quality.

The process of forming the parts by the above device based on the rotatable reflector is shown in fig. 3:

step 1: printing of parts

Starting the equipment, reading a part printing and dividing program, outputting laser by the high-power laser 1, starting printing the part on the substrate 5 by the laser through the dynamic focusing device 3 and the scanning galvanometer 4, and enabling the reflector 7 to be out of a laser light path at the moment, as shown in fig. 4. After the printing of the part is completed, the high power laser 1 is turned off.

Step 2: mirror rotation

The servo motor is controlled by a computer to drive the rotary reflector 7 to a designated position, and at the moment, the reflector 7 is positioned on a laser light path emitted by the high-power pulse laser 2 and can reflect laser light to enter the dynamic focusing device 3. The direction of rotation 8 of the mirror is shown in fig. 1.

And step 3: surface treatment of parts

Reading a part post-processing scanning program, turning on the high-power pulse laser 2, and starting surface processing on the part on the substrate 5 by the pulse laser through the dynamic focusing device 3 and the scanning galvanometer 4, wherein the position of the reflecting mirror 7 is shown in fig. 5. And finishing surface treatment, and turning off the high-power pulse laser.

The flow of the part forming is performed by the above-mentioned apparatus based on the half mirror set at 45 °, as shown in fig. 6:

step 1: printing of parts

The equipment is started, the part printing and splitting program is read, the high-power laser 1 outputs laser, and laser beams transmit through the back surface of the semi-transparent mirror 9 to start printing on the parts on the base material 5, as shown in fig. 7. After the printing of the part is completed, the high power laser 1 is turned off.

Step 2: surface treatment of parts

After reading the part post-processing scanning program, the high-power pulse laser 3 is turned on, the pulse laser totally reflects on the front surface of the semi-transparent mirror 9, and the surface processing of the part on the substrate 5 is started, as shown in fig. 8. The surface treatment is completed and the high power pulse laser 2 is turned off.

The utility model discloses a laser beam focus mode of preceding focus galvanometer (PRE-SCAN) for the facula is the same on every point of whole machined surface, has improved the precision that the part printed. The dynamic focusing can prolong the focal length, the scanning range of the laser is enlarged, the breadth size of the printed part is increased, and meanwhile, the high-precision forming of parts with larger sizes can be completed by splicing a plurality of vibrating mirrors.

The two lasers are used alternately, so that the high-efficiency forming of parts is guaranteed, the surface precision and roughness of the parts can be guaranteed, and the processing cost of the parts is reduced.

The high-power laser is adopted, the material is rapidly melted and bonded and formed without depending on the energy absorption of the material, the forming efficiency of parts is favorably improved, and the metal powder with large granularity can be used, and the large-particle metal powder is relatively cheap, so that the production cost is reduced.

Claims

1. An SLM high-power part forming device is characterized by comprising a laser beam combiner, a dynamic focusing device (3) and a scanning galvanometer (4) which are sequentially arranged;

the laser beam combiner comprises a high-power laser (1), a high-power pulse laser (2) and a laser conversion device (6), wherein the laser conversion device is used for realizing the alternate use of the high-power laser (1) and the high-power pulse laser (2).

2. An SLM high power parts forming device according to claim 1, characterized in that the laser conversion device is a mirror or a half mirror.

3. An SLM high power part shaping device as claimed in claim 2 where the mirror is rotatable.

4. An SLM high power part forming device according to claim 3, characterized in that the mirrors are connected to servo motors, which drive the mirrors to rotate.

5. An SLM high power part shaping device as claimed in claim 2 characterised in that the half mirror is arranged at 45 ° to the laser path.

6. An SLM high power part shaping device according to claim 1 characterized by that the high power laser (1), high power pulse laser (2) are arranged perpendicular to each other.