A spatter-free laser cold cutting method

Abstract

The present application provides a spatter-free laser cold cutting method, comprising clamping and positioning a workpiece to be cut on a clamping tool, determining parameters directly affecting the spatter-free cold cutting effect, wherein the parameters directly affecting the spatter-free cold cutting effect include a slit thickness and a slit temperature of the workpiece to be cut; selecting laser cutting parameters and designing a laser cutting process test; based on the laser cutting process test, screening out a cutting parameter group data interval range that satisfies the slit thickness; on the basis of the cutting parameter group data interval range, continuing to perform a laser cutting process test to optimize parameters, screening out cutting parameter group data that satisfies the slit temperature; performing a performance test on a sample workpiece cut with the cutting parameter group data; and screening out a group of optimized spatter-free process parameter group data for laser cold cutting based on the results of the performance test, thereby achieving spatter-free cold cutting of the workpiece and having the beneficial effect of ensuring cutting quality and safety.

Description

Technical Field

[0001] The invention relates to the technical field of laser cutting, and in particular to a spatter-free laser cold cutting method. Background Art

[0002] Laser cutting is an advanced processing technology. However, during the cutting process, the high energy density of the laser may cause the material to vaporize or melt rapidly. Fast and efficient laser cutting is usually accompanied by large sparks. The dust from the sparks is likely to remain in the structure of the workpiece being cut. At the same time, a large heat-affected zone is likely to be left on the surface of the cut, affecting the fixation and stability of the workpiece, and may even cause vibration and shaking, which will inevitably affect the safety of the cutting work and the quality of the cutting effect.

[0003] The principle of laser cold cutting is to use a high-energy laser beam to irradiate the surface of the material, convert light energy into heat energy, and partially melt or vaporize the material, thereby achieving cutting. In the prior art, it is generally believed that the sparks generated during laser cold cutting are a normal phenomenon, which has weakened the in-depth research on spatter-free laser cold cutting. Even if the laser cutting parameters such as the height and focal length of the laser beam, the laser power and the laser repetition frequency are adjusted to minimize the sparks, there is no specific parameter adjustment method for spatter-free laser cold cutting.

[0004] Therefore, it is urgent for researchers in this field to develop a spatter-free laser cold cutting method. Summary of the invention

[0005] In view of this, in order to solve the above-mentioned problems, an embodiment of the present invention provides a spatter-free laser cold cutting method, which screens out a set of optimized spatter-free process parameter group data for laser cold cutting, thereby realizing spatter-free cold cutting of the workpiece, while having the beneficial effect of ensuring the cutting quality and safety, avoiding the spark splashing generated in the existing laser cutting process, and the technical problems of poor cutting effect and low safety that may be caused.

[0006] To achieve the above object, an embodiment of the present invention provides a spatter-free laser cold cutting method, comprising the following steps:

[0007] Step S1, clamping and positioning the workpiece to be cut on the clamping tool, and determining the parameters directly affecting the spatter-free cold cutting effect, wherein the parameters directly affecting the spatter-free cold cutting effect include the slit thickness and slit temperature of the workpiece to be cut;

[0008] Step S2, selecting laser cutting parameters and designing laser cutting process tests;

[0009] Step S3, screening out a cutting parameter group data interval range that satisfies the cutting thickness according to a laser cutting process test;

[0010] Step S4, based on the range of the cutting parameter group data, continue to perform laser cutting process tests to optimize parameters, and screen out cutting parameter group data that meets the cutting seam temperature;

[0011] Step S5, performing a performance test on the sample workpiece cut using the cutting parameter group data;

[0012] Step S6: deriving the optimal spatter-free process parameter group data for laser cold cutting according to the results of the performance test.

[0013] Furthermore, in step S2, the laser cutting process test includes an orthogonal test and a univariate test.

[0014] Furthermore, in the step S3, based on the laser cutting process test, the data interval range of the cutting parameter group that meets the cutting thickness is screened out; specifically, the orthogonal test is used to screen out the data interval range of the cutting parameter group that meets the cutting thickness.

[0015] Furthermore, in step S4, based on the range of the cutting parameter group data, laser cutting process tests are continued to be performed to optimize parameters, and cutting parameter group data that meet the cutting seam temperature are screened out; specifically, based on the range of the cutting parameter group data obtained by the orthogonal test, the univariate test is further used to screen out cutting parameter group data that meet the cutting seam temperature.

[0016] Furthermore, the laser cutting parameters include laser pulse width, laser frequency, laser power and scanning speed.

[0017] Furthermore, the orthogonal test comprises the following steps:

[0018] Step S31, selecting four parameters with better cutting effects from the laser cutting parameters, and designing an orthogonal experiment with four factors and four levels, wherein the four factors are laser pulse width, laser frequency, laser power and scanning speed;

[0019] Step S32: According to the orthogonal test scheme of step S31, a data interval range of a cutting parameter group satisfying the cutting thickness is screened out.

[0020] Furthermore, the univariate test comprises the following steps:

[0021] Step S41, fixing the laser pulse width, laser frequency and scanning speed, and changing the laser power so that the cutting seam temperature is less than the preset temperature for cold cutting without spatter;

[0022] Step S42, fixing the laser pulse width, laser power and scanning speed, and changing the laser frequency so that the cutting seam temperature is less than the preset temperature for cold cutting without spatter;

[0023] Step S43: According to the optimization process of step S41 and step S42, two groups of cutting parameter group data satisfying the cutting seam temperature are screened out.

[0024] Further, in the step S5, the sample workpiece cut by using the cutting parameter group data is subjected to performance testing;

[0025] Specifically, the two groups of cutting parameter group data screened out in step S43 are used to perform laser cutting respectively to obtain two laser-cut sample workpieces, and tensile tests are performed on the two laser-cut sample workpieces to obtain tensile stress-strain curves, and the tensile properties of the two sample workpieces are compared, and the tensile fracture micromorphology is compared and observed.

[0026] Furthermore, based on the comparative analysis of the tensile properties of the two sample workpieces, the tensile fracture was observed and compared with the tensile fracture micromorphology using a scanning electron microscope, and a set of optimized spatter-free process parameter group data for laser cold cutting was obtained.

[0027] Beneficial effects of the present invention:

[0028] A spatter-free laser cold cutting method provided by the present invention specifically includes step S1, clamping and positioning the workpiece to be cut on the clamping tool, determining the parameters directly affecting the spatter-free cold cutting effect, wherein the parameters directly affecting the spatter-free cold cutting effect include the slit thickness and slit temperature of the workpiece to be cut; step S2, selecting laser cutting parameters and designing a laser cutting process test; step S3, based on the laser cutting process test, screening out a cutting parameter group data interval range that meets the slit thickness; step S4, on the basis of the cutting parameter group data interval range, continuing to perform laser cutting process tests to optimize parameters, and screening out cutting parameter group data that meets the slit temperature; step S5, performing a performance test on a sample workpiece cut with the cutting parameter group data; step S6, screening out a group of optimized spatter-free process parameter group data for laser cold cutting based on the results of the performance test, thereby achieving spatter-free cold cutting of the cut workpiece and having the beneficial effect of ensuring cutting quality and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The following drawings are used to provide a further understanding of the present application, constitute a part of the present application, and are only intended to provide an illustrative explanation and description of the present invention, and are not intended to limit the scope of the present invention. In the drawings:

[0030] Figure 1A flow chart of a spatter-free laser cold cutting method according to an embodiment of the present application;

[0031] Figure 2 This is a flow chart of a spatter-free laser cold cutting method according to another embodiment of the present application;

[0032] Figure 3 This is a flow chart of a spatter-free laser cold cutting method according to another embodiment of the present application;

[0033] Figure 4 The tensile stress-strain curves of the sample workpiece after laser cutting using two sets of cutting parameter data in the embodiment of the present application;

[0034] Figure 5 A schematic diagram of the tensile fracture microscopic morphology of the cutting parameter group data of parameter group 1 adopted in the embodiment of the present application;

[0035] Figure 6 This is a schematic diagram of the tensile fracture micromorphology of the cutting parameter group data of parameter group 2 used in the embodiment of the present application. DETAILED DESCRIPTION

[0036] Several embodiments of the present application will be disclosed below with diagrams to clearly and completely describe the technical solution of the present application, which constitute a part of the specification of the present application and are used to provide a further understanding of the present invention. The schematic embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0037] The technical solutions between the various embodiments of the present application can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0038] The following contents are all examples of specific implementation processes provided for describing in detail the technical solutions to be protected by this application. However, this application may also be implemented in other ways different from the descriptions herein. Persons skilled in the art may, under the guidance of the concepts of this application, adopt different technical means to implement this application. Therefore, this application is not limited to the specific embodiments below.

[0039] The present application provides a spatter-free laser cold cutting method, comprising the following steps: step S1, clamping and positioning the workpiece to be cut on a clamping tool, and determining the parameters directly affecting the spatter-free cold cutting effect, wherein the parameters directly affecting the spatter-free cold cutting effect include the slit thickness and slit temperature of the workpiece to be cut; step S2, selecting laser cutting parameters and designing a laser cutting process test; step S3, based on the laser cutting process test, screening out a cutting parameter group data interval range that satisfies the slit thickness; step S4, on the basis of the cutting parameter group data interval range, continuing to perform a laser cutting process test to optimize parameters, and screening out cutting parameter group data that satisfies the slit temperature; step S5, performing a performance test on a sample workpiece cut using the cutting parameter group data; step S6, based on the results of the performance test, obtaining the optimal spatter-free process parameter group data for laser cold cutting, thereby achieving spatter-free cold cutting of the cut workpiece, while having the beneficial effect of ensuring cutting quality and safety.

[0040] Specifically, see Figure 1 The flowchart shown is a method for screening a spatter-free laser cold cutting method to obtain an optimized spatter-free process parameter group data for laser cold cutting.

[0041] This embodiment uses the Raptor-100 laser equipment to take a 1.5mm thick aluminum alloy sheet as the workpiece to be cut as an example to illustrate the method steps for optimizing and screening the spatter-free process parameter group data for laser cold cutting. First, the 1.5mm thick aluminum alloy sheet is clamped and positioned on the clamping tool, and the cutting path is set so that the laser beam with the laser head height and focal length adjusted can cut along the cutting path. Determine the parameters directly affecting the spatter-free cold cutting effect, which include the slit thickness and slit temperature of the workpiece to be cut;

[0042] It should be noted that the clamping tool of this embodiment is a commonly used clamp used in existing laser cutting. The aluminum alloy plate has a thickness of 1.5 mm as the cutting thickness, and a preset temperature of less than 150°C for spatter-free cold cutting of the aluminum alloy plate. That is, a necessary condition for achieving spatter-free aluminum alloy plate during efficient laser cold cutting is that the cutting temperature cannot be greater than 150°C.

[0043] To achieve laser cutting, we first need to verify the parameter range for completely cutting the 1.5mm thick aluminum alloy plate. This application uses the orthogonal test method to explore the parameter range to achieve the experimental goal. For details, please refer to Figure 2The specific steps of using the orthogonal test are as follows: step S31, selecting four parameters with better cutting effects from the laser cutting parameters, designing a four-factor four-level orthogonal test, wherein the four factors are laser pulse width, laser frequency, laser power and scanning speed; step S32, according to the orthogonal test scheme of step S31, screening and obtaining the data interval range of the cutting parameter group that meets the slit thickness, and the orthogonal test table is shown as follows:

[0044]

[0045] It can be seen that this application changes the four parameter factors of laser pulse width, laser frequency, laser power and scanning speed in the laser cutting parameters, and sets 4 levels for each parameter factor using the orthogonal experimental method to screen out the cutting parameter group data range that can completely cut the aluminum alloy plate with a cutting thickness of 1.5 mm: laser pulse width 200ns, laser frequency 70~170KHz, laser power 80~100W and scanning speed 100~200mm / min.

[0046] Furthermore, based on the data interval range of the cutting parameter group, the process parameters are further optimized through a single variable test method, in order to achieve maximum cutting efficiency without spatter and overheating. Figure 3 The steps of the single variable test are as follows: step S41, fix the laser pulse width, laser frequency and scanning speed, change the laser power, so that the cutting temperature is less than the preset temperature of spatter-free cold cutting; step S42, fix the laser pulse width, laser power and scanning speed, change the laser frequency, so that the cutting temperature is less than the preset temperature of spatter-free cold cutting; step S43, according to the optimization process of step S41 and step S42, screen out two groups of cutting parameter group data that meet the cutting temperature.

[0047] It should be noted that, since the laser pulse width and scanning speed have little effect on the kerf temperature, when the scanning speed is greater than 200mm / min, the kerf depth will become shallower and shallower as the scanning speed increases. Therefore, a fixed laser pulse width of 200ns and a scanning speed of 100mm / min are used to continue the single variable test by changing the laser frequency and laser power respectively, in order to achieve the necessary and sufficient conditions for spatter-free cold cutting: Under the premise of ensuring the kerf depth, the kerf temperature is lower than the preset temperature of 150℃ for spatter-free cold cutting. The single variable test table is as follows:

[0048]

[0049] According to the above table, further screening can be directly carried out to obtain the optimization results: under the premise of ensuring the cutting depth, the cutting temperature is made lower than the preset temperature of 150°C for cold cutting without spatter. The two groups of cutting parameter group data are: parameter group 1: laser pulse width 200ns, laser repetition frequency 130KHz, laser power 90W, scanning speed 100mm / min; parameter group 2: laser pulse width 200ns, laser repetition frequency 110KHz, laser power 80W, scanning speed 100mm / min.

[0050] As a preferred embodiment, in step S5, a performance test is performed on the sample workpiece cut by using the cutting parameter group data; specifically, laser cutting is performed respectively by using the two groups of cutting parameter group data selected in step S43 to obtain two laser-cut sample workpieces, and a tensile test is performed on the two laser-cut sample workpieces, see Figure 4 As shown, the tensile stress-strain curves of parameter group 1, parameter group 2 and the base material are obtained, and the tensile strength of the sample is calculated by the tensile stress. The tensile strength is calculated using the following formula:

[0051]

[0052] Where, σ represents the tensile strength, F b represents the maximum tensile stress, and S represents the cross-sectional area of ​​the specimen. The tensile properties of the two specimens are compared.

[0053] It should be noted that since laser cutting will affect the material itself and thus affect the material properties, the significance of testing the tensile properties here is to explore whether the cutting method has an impact on the material properties. The tensile properties of the plate after cutting should reach at least 90% of the parent material itself, which is conducive to ensuring that this application can further confirm the actual use of the material under the premise of achieving the technical effect of spatter-free cold cutting.

[0054] Further, based on the comparative analysis of the tensile properties of the two specimens, see Figure 4 , Figure 5 The tensile fracture was observed and compared with the microscopic morphology using a scanning electron microscope, and it was found that parameter group 2 was the optimal spatter-free process parameter group for laser cold cutting, that is, the laser pulse width was 200ns, the laser repetition frequency was 110KHz, the laser power was 80W, and the scanning speed was 100mm / min.

[0055] In summary, a spatter-free laser cold cutting method provided by the present invention specifically includes step S1, clamping and positioning the workpiece to be cut on the clamping tool, and determining the parameters directly affecting the spatter-free cold cutting effect, wherein the parameters directly affecting the spatter-free cold cutting effect include the slit thickness and slit temperature of the workpiece to be cut; step S2, selecting laser cutting parameters and designing a laser cutting process test; step S3, based on the laser cutting process test, screening out the cutting parameter group data interval range that meets the slit thickness; step S4, on the basis of the cutting parameter group data interval range, continuing to perform laser cutting process tests to optimize parameters, and screening out cutting parameter group data that meets the slit temperature; step S5, performing a performance test on a sample workpiece cut with the cutting parameter group data; step S6, screening out a set of optimized spatter-free process parameter group data for laser cold cutting based on the results of the performance test, so as to achieve spatter-free cold cutting of the cut workpiece, while having the beneficial effect of ensuring cutting quality and safety.

[0056] The present application is described with reference to flowcharts and / or block diagrams of methods and computer program products according to embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. Instructions executed by a processor of a computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0057] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0058] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0059] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0060] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A spatter-free laser cold cutting method, characterized in that: The steps include: Step S1, clamping and positioning the workpiece to be cut on the clamping tool, and determining the parameters directly affecting the spatter-free cold cutting effect, wherein the parameters directly affecting the spatter-free cold cutting effect include the slit thickness and slit temperature of the workpiece to be cut; Step S2, selecting laser cutting parameters and designing a laser cutting process experiment, wherein the laser cutting process experiment includes an orthogonal experiment and a univariate experiment; Step S3, according to the laser cutting process test, screening out the data interval range of the cutting parameter group that meets the slit thickness; specifically, using the orthogonal test to screen out the data interval range of the cutting parameter group that meets the slit thickness; Step S4, based on the range of the cutting parameter group data, continue to perform laser cutting process experiments to optimize parameters, and screen out the cutting parameter group data that meets the cutting seam temperature; specifically, based on the range of the cutting parameter group data obtained by the orthogonal experiment, further use the univariate experiment to screen out the cutting parameter group data that meets the cutting seam temperature; Step S5, performing a performance test on the sample workpiece cut using the cutting parameter group data; Step S6, obtaining the optimal spatter-free process parameter group data for laser cold cutting according to the results of the performance test; Wherein, the orthogonal test comprises the following steps: Step S31, selecting four parameters with better cutting effects from the laser cutting parameters, and designing an orthogonal experiment with four factors and four levels, wherein the four factors are laser pulse width, laser frequency, laser power and scanning speed; Step S32, according to the orthogonal test scheme of step S31, screen and obtain the data interval range of the cutting parameter group that meets the cutting thickness; The univariate test comprises the following steps: Step S41, fixing the laser pulse width, laser frequency and scanning speed, and changing the laser power so that the cutting seam temperature is less than the preset temperature for cold cutting without spatter; Step S42, fixing the laser pulse width, laser power and scanning speed, and changing the laser frequency so that the cutting seam temperature is less than the preset temperature for cold cutting without spatter; Step S43: According to the optimization process of step S41 and step S42, two groups of cutting parameter group data satisfying the cutting seam temperature are screened out.

2. The spatter-free laser cold cutting method according to claim 1, characterized in that: In the step S5, a performance test is performed on the sample workpiece cut using the cutting parameter group data; Specifically, the two groups of cutting parameter group data screened out in step S43 are used to perform laser cutting respectively to obtain two laser-cut sample workpieces, and tensile tests are performed on the two laser-cut sample workpieces to obtain tensile stress-strain curves, and the tensile properties of the two sample workpieces are compared, and the tensile fracture micromorphology is compared and observed.

3. The spatter-free laser cold cutting method according to claim 2, characterized in that: Based on the comparative analysis of the tensile properties of the two sample workpieces and the observation and comparison of the tensile fracture micromorphology using a scanning electron microscope, a set of optimized spatter-free process parameter group data for laser cold cutting was obtained.

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