In-situ real-time measurement device and method for high-frequency pulse laser impact force

Abstract

The invention relates to an in-situ real-time measurement device and method for high-frequency pulse laser impact force, and the device comprises a substrate and a fixed plate. An in-situ measurement chamber; the in-situ measurement system is used for detecting the strain borne by the substrate when the laser shocks the melting layer, obtaining a strain electric signal corresponding to the strain and carrying out preset signal analysis and processing operation on the strain electric signal so as to obtain a target strain modulation signal corresponding to the strain electric signal; a lead screw; the oscilloscope is used for receiving the target strain modulation signal and demodulating the target strain modulation signal to obtain a final target strain signal; and the calculation module is used for calculating an external force borne by a preset surface acoustic wave strain sensor in the in-situ measurement system based on the preset stress-strain relationship and the final target strain signal so as to calculate the pulse laser impact force measured in real time in situ according to the external force. Therefore, the problems of insufficient calculation precision, poor operability or incapability of working in a high-temperature environment in the prior art are solved.

Description

Technical Field

[0001] The present application relates to the technical field of laser shock and laser selective melting composite manufacturing, and in particular to an in-situ real-time measurement device and method for high-frequency pulse laser shock force. Background Art

[0002] Laser shock peening (LSP) is an advanced surface treatment technology that modifies the surface of materials through shock waves generated by high-energy laser beams, which can effectively improve the internal stress distribution state of metal materials and improve the mechanical properties of parts. However, due to the high pressure, extremely short action time and fast attenuation of shock waves induced by high-frequency strong lasers, the accurate measurement of laser impact force has always been a technical difficulty in this field. For the laser shock and laser selective melting composite manufacturing technology developed in recent years, the in-situ measurement of laser impact force is even more lacking, on the one hand because of the limited space of the printer cavity, and on the other hand because the printing layer will generate a high temperature of more than 500°C. In related technologies, the main methods for measuring laser impact force include PVDF sensors, impact pendulum method and theoretical model calculation. However, these measurement methods are either insufficient in accuracy, or cannot be in-situ or are not resistant to high temperatures. For laser shock and laser selective melting composite manufacturing technology, there is an urgent need for a feasible laser impact force measurement method. Summary of the invention

[0003] The present application provides an in-situ real-time measurement device and method for high-frequency pulse laser impact force to solve the problems of insufficient calculation accuracy, poor operability or inability to work in high temperature environments in related technologies.

[0004] The first aspect of the present application provides an in-situ real-time measurement device for high-frequency pulse laser impact force, comprising: a substrate and a fixed plate; an in-situ measurement cavity, the in-situ measurement cavity is connected to the substrate and the fixed plate; an in-situ measurement system, the in-situ measurement system is mounted in the in-situ measurement cavity, and is used to detect the strain of the substrate when the laser impacts the melting layer, and obtain the strain electrical signal corresponding to the strain, and perform a preset signal analysis and processing operation on the strain electrical signal to obtain a target strain modulation signal corresponding to the strain electrical signal; a lead screw, the lead screw is connected to the fixed plate, and is used to measure the target strain of the substrate when the laser is selected. After each layer of the zone melting SLM device is formed, the lead screw descends by a layer thickness so that the uppermost layer is located on the original plane; the oscilloscope is used to receive the target strain modulation signal, and demodulate the target strain modulation signal to obtain the final target strain signal, and display the final target strain signal on the screen of the oscilloscope; the calculation module is used to calculate the external force exerted on the surface acoustic wave strain sensor preset in the in-situ measurement system based on the preset stress-strain relationship and the final target strain signal, so as to calculate the pulsed laser impact force measured in real time in situ according to the external force.

[0005] Optionally, in one embodiment of the present application, the in-situ measurement system includes: the surface acoustic wave strain sensor, which is located in the groove of the substrate and is used to detect the strain exerted on the substrate when the laser impact melts the layer, and obtain a strain electrical signal corresponding to the strain; a data acquisition system, which is used to perform signal conditioning, conversion and modulation operations on the strain electrical signal to obtain the target strain modulation signal.

[0006] Optionally, in one embodiment of the present application, the data acquisition system includes: a signal conditioning module, used to amplify and process the strain electrical signal to generate an amplified strain electrical signal, and filter the amplified strain electrical signal to obtain a filtered strain electrical signal, and linearize the filtered strain electrical signal to generate a conditioned strain electrical signal; a first signal processing module, used to perform digital signal conversion on the conditioned strain electrical signal to generate a converted strain electrical signal, and modulate the converted strain electrical signal to generate the target strain modulation signal; a signal transmission module, used to transmit the target strain modulation signal to the outside of the laser selective melting SLM device.

[0007] Optionally, in one embodiment of the present application, the oscilloscope includes: a demodulator, used to demodulate the target strain modulation signal to generate a strain demodulated electrical signal; a second signal processing module, used to filter and amplify the strain demodulated electrical signal to obtain the final target strain signal; and a display unit, used to display the final target strain signal in a preset waveform form.

[0008] Optionally, in one embodiment of the present application, the calculation formula of the pulse laser impact force is:

[0009] F=σA=EAε=EA(f 1 -f 0 ) / k(N),

[0010] P=Eε(Pa),

[0011] Wherein, σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact area, k is the strain coefficient, and f 1 is the resonant frequency of the surface acoustic wave strain sensor, f 0 is the initial resonant frequency of the surface acoustic wave strain sensor.

[0012] A second aspect of the present application provides an in-situ real-time measurement method for high-frequency pulse laser impact force, comprising the following steps: detecting the strain of a preset substrate when the laser impacts a melting layer, and acquiring a strain electrical signal corresponding to the strain, and performing a preset signal analysis and processing operation on the strain electrical signal to obtain a target strain modulation signal corresponding to the strain electrical signal; receiving the target strain modulation signal, and demodulating the target strain modulation signal to obtain a final target strain signal, and displaying the final target strain signal on a preset oscilloscope screen; calculating the external force exerted on a preset surface acoustic wave strain sensor based on a preset stress-strain relationship and the final target strain signal, so as to calculate the in-situ real-time measured pulse laser impact force based on the external force.

[0013] Optionally, in one embodiment of the present application, the calculation formula of the pulse laser impact force is:

[0014] F=σA=EAε=EA(f 1 -f 0 ) / k(N),

[0015] P=Eε(Pa),

[0016] Wherein, σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact area, k is the strain coefficient, and f 1 is the resonant frequency of the surface acoustic wave strain sensor, f 0 is the initial resonant frequency of the surface acoustic wave strain sensor.

[0017] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement an in-situ real-time measurement method for high-frequency pulse laser impact force as described in the above embodiment.

[0018] The fourth aspect of the present application provides a computer-readable storage medium, which stores a computer program. When the program is executed by a processor, it implements the above-mentioned in-situ real-time measurement method of high-frequency pulse laser impact force.

[0019] The fifth aspect of the present application provides a computer program product, which stores a computer program. When the program is executed by a processor, it implements the above-mentioned in-situ real-time measurement method of high-frequency pulse laser impact force.

[0020] The embodiment of the present application has the advantages of high sensitivity, fast response speed and high temperature resistance, and can measure the laser impact force in the laser selective melting and laser shock strengthening composite additive manufacturing in real time without changing the original structure and operating conditions of the SLM printer. Thus, the problems of insufficient calculation accuracy, poor operability or inability to work in high temperature environments in related technologies are solved.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0023] Figure 1 It is a structural schematic diagram of an in-situ real-time measurement device of high-frequency pulse laser impact force provided according to an embodiment of the present application;

[0024] Figure 2 A schematic diagram of the position of the in-situ measurement cavity in the SLM printer cavity according to one embodiment of the present application;

[0025] Figure 3 A schematic diagram of the design of an in-situ measurement chamber according to an embodiment of the present application;

[0026] Figure 4 A schematic diagram of an in-situ measurement process of laser impact force in laser selective melting and laser shock strengthening composite additive manufacturing according to an embodiment of the present application;

[0027] Figure 5A flowchart of an in-situ real-time measurement method of high-frequency pulse laser impact force provided according to an embodiment of the present application;

[0028] Figure 6 It is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0029] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0030] The following describes an in-situ real-time measurement device and method for high-frequency pulse laser impact force according to an embodiment of the present application with reference to the accompanying drawings. In view of the problems of insufficient calculation accuracy, poor operability or inability to work in high-temperature environments in the related technologies mentioned in the above background technology, the present application provides an in-situ real-time measurement device for high-frequency pulse laser impact force. In the device, there are advantages such as high sensitivity, fast response speed and high temperature resistance. Without changing the original structure and operating conditions of the SLM printer, the in-situ real-time measurement of the laser impact force in laser selective melting and laser shock strengthening composite additive manufacturing can be performed. As a result, the problems of insufficient calculation accuracy, poor operability or inability to work in high-temperature environments in the related technologies are solved.

[0031] Specifically, Figure 1 A schematic diagram of the structure of an in-situ real-time measurement device for high-frequency pulse laser impact force provided in an embodiment of the present application.

[0032] like Figure 1 As shown, the in-situ real-time measurement device 10 of high-frequency pulse laser impact force includes: a substrate 100, a fixing plate 200, an in-situ measurement cavity 300, an in-situ measurement system 400, a lead screw 500, an oscilloscope 600 and a calculation module 700.

[0033] Specifically, a base plate 100 and a fixing plate 200 .

[0034] It can be understood that the substrate 100 in the embodiment of the present application is fastened to the upper surface of the in-situ measurement cavity 300 , and the fixing plate 200 is captively connected to the lower surface of the in-situ measurement cavity 300 .

[0035] The in-situ measurement chamber 300 is connected to the substrate 100 and the fixing plate 200 .

[0036] It can be understood that the in-situ measurement chamber 300 in the embodiment of the present application is designed to be composed of 6 metal plates of a certain thickness, which are detachable and can be adapted and installed in the printing platforms of various SLM printers without any modification to the machine.

[0037] In the actual implementation process, the in-situ measurement cavity 300 in the embodiment of the present application is connected to the substrate 100 and the fixing plate 200, and adopts a sealing design to prevent the splashing of metal powder during the laser processing from damaging the measuring equipment or affecting the measurement accuracy. Figure 2 As shown, the design of the in-situ measurement chamber 300 is as follows Figure 3 shown.

[0038] The in-situ measurement system 400 is mounted in the in-situ measurement cavity 300 and is used to detect the strain exerted on the substrate 100 when the laser impact melts the layer, obtain the strain electrical signal corresponding to the strain, and perform a preset signal analysis and processing operation on the strain electrical signal to obtain a target strain modulation signal corresponding to the strain electrical signal.

[0039] Furthermore, the embodiments of the present application can also detect the strain exerted on the substrate 100 when the laser impact melts the layer through the in-situ measurement system 400, obtain the strain electrical signal corresponding to the strain, and perform signal conditioning, conversion, modulation and storage and other processing operations on the strain electrical signal, so as to obtain the target strain modulation signal corresponding to the strain electrical signal.

[0040] Optionally, in one embodiment of the present application, the in-situ measurement system 400 includes: a surface acoustic wave strain sensor and a data acquisition system.

[0041] Among them, the surface acoustic wave strain sensor is located in the groove of the substrate and is used to detect the strain exerted on the substrate when the laser impacts the melting layer and obtain the strain electrical signal corresponding to the strain.

[0042] The data acquisition system is used to perform signal conditioning, conversion and modulation operations on the strain electrical signal to obtain the target strain modulation signal.

[0043] It should be noted that, in the embodiment of the present application, the in-situ measurement system 400 mainly includes a surface acoustic wave strain sensor and a data acquisition system.

[0044] Specifically, a groove is provided on the lower surface of the substrate 100. In the embodiment of the present application, a surface acoustic wave strain sensor (SAW) can be placed in the groove to ensure that the sensor is in close contact with the sample, thereby detecting the tiny strain exerted on the substrate when the laser impacts the melting layer; in addition, an opening is provided in the middle of the upper plate of the measuring cavity, and the wire connected to the SAW strain sensor can enter the measuring cavity through the opening.

[0045] Secondly, the embodiments of the present application utilize the piezoelectric effect through the SAW strain sensor to convert the surface acoustic wave affected by the strain into a corresponding electrical signal (i.e., a strain electrical signal). The electrical signal differs from the original radio frequency electrical signal in terms of amplitude, phase, etc., and this difference reflects the information of the external strain. Afterwards, the embodiments of the present application can utilize the data acquisition system in the measurement cavity to perform signal conditioning, conversion, and modulation operations on the strain electrical signal, thereby obtaining the target strain modulation signal, providing reliable data support for the subsequent calculation of the pulsed laser impact force.

[0046] It can be understood that the SAW sensor in the embodiment of the present application can adapt to the high-temperature working environment of the SLM cavity, which is not available in the PVDF sensor (Curie temperature is only 90° C.).

[0047] Optionally, in one embodiment of the present application, the data acquisition system includes: a signal conditioning module, a first signal processing module and a signal transmission module.

[0048] Among them, the signal conditioning module is used to amplify and process the strain electrical signal to generate an amplified strain electrical signal, and filter the amplified strain electrical signal to obtain a filtered strain electrical signal, and linearize the filtered strain electrical signal to generate a conditioned strain electrical signal.

[0049] The first signal processing module is used to perform digital signal conversion on the conditioned strain electrical signal to generate a converted strain electrical signal, and modulate the converted strain electrical signal to generate a target strain modulation signal.

[0050] The signal transmitting module is used to transmit the target strain modulation signal to the outside of the laser selective melting SLM device.

[0051] It should be noted that if Figure 4 As shown, the data acquisition system in the embodiment of the present application is mainly composed of a signal conditioning module, a signal acquisition and processing module (ie, a first signal processing module) and a signal transmission module.

[0052] Specifically, the signal conditioning module mainly includes a signal amplification and filtering part and a linearization processing part.

[0053] Among them, signal amplification and filtering part: Since the signal output by the sensor may be weak and contain noise, it needs to be amplified and filtered through the signal conditioning module, which helps to improve the signal-to-noise ratio and ensure the accuracy of subsequent data collection;

[0054] Linearization processing part: In some cases, there may be a nonlinear relationship between the signal output by the sensor and the actual strain. Therefore, it is necessary to eliminate this nonlinear effect through linear processing so that the output signal can more accurately reflect the actual strain.

[0055] Secondly, the embodiments of the present application can convert the conditioned electrical signal into a digital signal through a signal acquisition and processing module, and modulate the electrical signal, which is conducive to wireless transmission and can improve anti-interference ability; thereafter, the embodiments of the present application can collect and store the modulated electrical signal (i.e., the target strain modulation signal).

[0056] Finally, the embodiment of the present application can transmit the modulated electrical signal to the outside of the SLM device through a wireless transmitter (such as a radio frequency module).

[0057] The lead screw 500 is connected to the fixing plate 200 and is used to lower the lead screw 500 by a layer thickness after each layer of the laser selective melting SLM device is formed, so that the uppermost layer is located on the original plane.

[0058] As a feasible method, the lower surface of the in-situ measurement cavity 300 is fastened to the fixed plate 200, and the upper surface is fastened to the substrate 100; and during the lifting process of the lead screw, the in-situ measurement cavity 300 is also lifted and lowered therewith, so that the substrate 100 can be located on the original plane (before the measurement cavity is installed), without affecting the normal powder laying and printing of the SLM equipment.

[0059] The embodiment of the present application does not require any modification to the machine, and has high-frequency response capability and high sensitivity, and can measure the impact force of high-frequency pulsed laser in situ. This application mode breaks through the limitations of traditional measurement methods and realizes real-time monitoring and accurate measurement of the impact force of high-frequency pulsed laser.

[0060] The oscilloscope 600 is used to receive the target strain modulation signal, and demodulate the target strain modulation signal to obtain a final target strain signal, and display the final target strain signal on the screen of the oscilloscope 600 .

[0061] Furthermore, in the embodiment of the present application, a high-precision oscilloscope 600 with a wireless receiving function may be configured outside the SLM cavity to receive the wireless signal (ie, the target strain modulation signal) transmitted from the SAW sensor.

[0062] Optionally, in one embodiment of the present application, the oscilloscope 600 includes: a demodulator, a second signal processing module and a display unit.

[0063] The demodulator is used to demodulate the target strain modulation signal to generate a strain demodulation electrical signal.

[0064] The second signal processing module is used to filter and amplify the strain demodulation electrical signal to obtain a final target strain signal.

[0065] The display unit is used to display the final target strain signal in a preset waveform form.

[0066] In an embodiment of the present application, after receiving the wireless signal, the oscilloscope 600 can demodulate the received wireless signal through a demodulator inside the oscilloscope 600 to restore it to the original strain information electrical signal (i.e., the strain demodulated electrical signal); thereafter, the embodiment of the present application performs signal processing such as filtering and amplification on the demodulated electrical signal (i.e., the strain demodulated electrical signal) through a second signal processing module to obtain the final target strain signal; finally, the embodiment of the present application can send the processed signal (i.e., the strain demodulated electrical signal) to the display unit of the oscilloscope 600, and display it on a display unit such as a screen in the form of a waveform graph.

[0067] The calculation module 700 is used to calculate the external force applied to the surface acoustic wave strain sensor preset in the in-situ measurement system 400 based on the preset stress-strain relationship and the final target strain signal, so as to calculate the pulsed laser impact force measured in real time in situ according to the external force.

[0068] Those skilled in the art should understand that, based on the piezoelectric effect, when the SAW sensor is subjected to an external force causing the piezoelectric material to deform, the propagation speed, frequency or phase of the SAW will change. Therefore, by measuring the above changes, the strain caused by the external force can be inferred. Therefore, the embodiment of the present application can calculate the external force on the SAW sensor based on the stress-strain relationship described by the material constitutive equation based on the calculation module 700, and then obtain the magnitude of the laser impact force.

[0069] Optionally, in one embodiment of the present application, the calculation formula of the pulse laser impact force is:

[0070] F=σA=EAε=EA(f 1 -f 0 ) / k(N),

[0071] P=Eε(Pa),

[0072] Where σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact area, k is the strain coefficient, and f 1is the resonant frequency of the surface acoustic wave strain sensor, f 0 is the initial resonant frequency of the surface acoustic wave strain sensor.

[0073] Specifically, the process of calculating the pulse laser impact force in the embodiment of the present application is as follows:

[0074] 1. Measure the change of resonant frequency:

[0075] (1) Measuring the initial resonant frequency: Before the strain is applied, first measure and record the initial resonant frequency f0 of the SAW sensor;

[0076] (2) Measuring the resonant frequency after laser shock: The laser is applied to the melt layer, and the impact force is transmitted to the SAW surface to generate strain. The resonant frequency f1 of the SAW sensor is measured and recorded again.

[0077] (3) The frequency shift of the SAW sensor before and after the laser shock is Δf = f1-f0;

[0078] 2. Calculate the strain generated:

[0079] In the embodiment of the present application, the strain of the SAW sensor can be expressed as:

[0080] Δf=kε

[0081] Where k is the gauge factor, which is a constant related to the SAW resonator design and material properties;

[0082] 3. Calculate stress:

[0083] In the elastic range, the stress obtained by the embodiment of the present application according to the stress-strain relationship is shown as follows:

[0084] σ=Eε

[0085] Wherein, E is the elastic modulus of the substrate material;

[0086] 4. Calculate the laser impact force:

[0087] F=σA

[0088] Where A is the area of ​​the laser impact region;

[0089] Substituting the above equations into the equation, we can get the magnitude of the laser impact force, as shown in the following equation:

[0090] F=σA=EAε=EA(f1-f0) / k(N)

[0091] P=Eε(Pa)

[0092] Where σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact area, k is the strain coefficient, and f 1 is the resonant frequency of the surface acoustic wave strain sensor, f 0 is the initial resonant frequency of the surface acoustic wave strain sensor.

[0093] Afterwards, the embodiment of the present application can also verify the laser impact force frequency, that is, by analyzing the frequency characteristics of the electrical signal output by the SAW sensor, thereby determining the impact force frequency of the high-frequency pulse laser.

[0094] The following is a specific example to further illustrate the calculation process of the pulse laser impact force in the embodiment of the present application.

[0095] In a specific embodiment of the present application, it is assumed that the metal thin substrate is Haynes 230 nickel-based superalloy material, the elastic modulus E is 227 GPa, and the measurement area of ​​the sensor is 10 mm 2 , select a high-sensitivity and high-linearity SAW sensor in the GHz frequency band, the strain factor k = 10GHz / με, if the frequency shift measured after laser shock is 1GHz, then the strain ε = Δf / k = 1GHz / (10GHz / με) = 0.1με.

[0096] Substitute the above values ​​into the calculation formula of external force F to obtain:

[0097] F = 227 × 10 9 Pa×10 -3 ×1×10 -5 m 2 =2270N

[0098] P = 227 × 10 9 Pa×10 -3 =227MPa

[0099] Therefore, the SAW sensor in the embodiment of the present application has a wide measurement range, thereby being able to meet various pulsed laser impact force measurement requirements from low frequency to high frequency; in addition, the embodiment of the present application has the advantages of high sensitivity, fast response speed and high temperature resistance, and can perform in-situ real-time measurement of laser impact force in laser selective melting and laser shock strengthening composite additive manufacturing without changing the original structure and operating conditions of the SLM printer.

[0100] It should be noted that the present application can be applied to the in-situ real-time measurement of impact force or pressure parameters of other surface treatment methods, including laser shock peening, shot peening and ultrasonic shock peening, etc. Surface treatment can effectively refine grains, hinder crack propagation, and improve the mechanical properties of materials.

[0101] According to the in-situ real-time measurement device of high-frequency pulse laser impact force proposed in the embodiment of the present application, it has the advantages of high sensitivity, fast response speed and high temperature resistance, and can measure the laser impact force in the laser selective melting and laser shock strengthening composite additive manufacturing in real time without changing the original structure and operating conditions of the SLM printer. Thus, the problems of insufficient calculation accuracy, poor operability or inability to work in high temperature environment in the related technologies are solved.

[0102] Next, a method for in-situ real-time measurement of high-frequency pulse laser impact force proposed in accordance with an embodiment of the present application will be described with reference to the accompanying drawings.

[0103] Figure 5 It is a flow chart of an in-situ real-time measurement method of high-frequency pulse laser impact force according to an embodiment of the present application.

[0104] like Figure 5 As shown, the in-situ real-time measurement method of high-frequency pulse laser impact force comprises the following steps:

[0105] Step S501: detecting the strain of the preset substrate when the laser impact melts the layer, acquiring a strain electrical signal corresponding to the strain, and performing a preset signal analysis and processing operation on the strain electrical signal to obtain a target strain modulation signal corresponding to the strain electrical signal.

[0106] Step S502: receiving a target strain modulation signal, and performing demodulation processing on the target strain modulation signal to obtain a final target strain signal, and displaying the final target strain signal on a preset oscilloscope screen.

[0107] Step S503: calculating the external force applied to the preset surface acoustic wave strain sensor based on the preset stress-strain relationship and the final target strain signal, so as to calculate the pulsed laser impact force measured in situ and in real time according to the external force.

[0108] Optionally, in one embodiment of the present application, the calculation formula of the pulse laser impact force is:

[0109] F=σA=EAε=EA(f 1 -f 0 ) / k(N),

[0110] P=Eε(Pa),

[0111] Where σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact area, k is the strain coefficient, and f 1 is the resonant frequency of the surface acoustic wave strain sensor, f 0 is the initial resonant frequency of the surface acoustic wave strain sensor.

[0112] It should be noted that the above explanation of an embodiment of an in-situ real-time measurement device for high-frequency pulse laser impact force is also applicable to an in-situ real-time measurement method for high-frequency pulse laser impact force of this embodiment, which will not be repeated here.

[0113] According to the in-situ real-time measurement method of high-frequency pulse laser impact force proposed in the embodiment of the present application, it has the advantages of high sensitivity, fast response speed and high temperature resistance, and can measure the laser impact force in the laser selective melting and laser shock strengthening composite additive manufacturing in real time without changing the original structure and operating conditions of the SLM printer. Thus, the problem of insufficient calculation accuracy, poor operability or inability to work in high temperature environment in the related technology is solved.

[0114] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0115] A memory 601 , a processor 602 , and a computer program stored in the memory 601 and executable on the processor 602 .

[0116] When the processor 602 executes the program, an in-situ real-time measurement method of the high-frequency pulse laser impact force provided in the above embodiment is implemented.

[0117] Furthermore, the electronic device further comprises:

[0118] The communication interface 603 is used for communication between the memory 601 and the processor 602 .

[0119] The memory 601 is used to store computer programs that can be executed on the processor 602 .

[0120] The memory 601 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0121] If the memory 601, the processor 602 and the communication interface 603 are implemented independently, the communication interface 603, the memory 601 and the processor 602 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 6Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0122] Optionally, in a specific implementation, if the memory 601, the processor 602 and the communication interface 603 are integrated on a chip, the memory 601, the processor 602 and the communication interface 603 can communicate with each other through an internal interface.

[0123] The processor 602 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0124] This embodiment also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned in-situ real-time measurement method of high-frequency pulse laser impact force is implemented.

[0125] An embodiment of the present application also provides a computer program product on which a computer program is stored. When the program is executed by a processor, the above-mentioned in-situ real-time measurement method of high-frequency pulse laser impact force is implemented.

[0126] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0127] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0128] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

Claims

1. An in-situ real-time measurement device for high-frequency pulse laser impact force, characterized in that: include: Base plates and fixing plates; An in-situ measurement cavity, wherein the in-situ measurement cavity is connected to the base plate and the fixing plate; An in-situ measurement system, which is mounted in the in-situ measurement cavity and is used to detect the strain of the substrate when the laser impact melts the layer, obtain a strain electrical signal corresponding to the strain, and perform a preset signal analysis and processing operation on the strain electrical signal to obtain a target strain modulation signal corresponding to the strain electrical signal; A lead screw connected to the fixed plate, used for lowering the lead screw by a layer thickness after each layer of the laser selective melting SLM device is formed, so that the uppermost layer is located on the original plane; an oscilloscope, used for receiving the target strain modulation signal, demodulating the target strain modulation signal to obtain a final target strain signal, and displaying the final target strain signal on a screen of the oscilloscope; The calculation module is used to calculate the external force exerted on the surface acoustic wave strain sensor preset in the in-situ measurement system based on the preset stress-strain relationship and the final target strain signal, so as to calculate the pulsed laser impact force measured in real time in situ according to the external force.

2. The in-situ real-time measurement device for high-frequency pulse laser impact force according to claim 1, characterized in that: The in-situ measurement system comprises: The surface acoustic wave strain sensor is located in the groove of the substrate and is used to detect the strain of the substrate when the laser impact melts the layer and obtain a strain electrical signal corresponding to the strain; The data acquisition system is used to perform signal conditioning, conversion and modulation operations on the strain electrical signal to obtain the target strain modulation signal.

3. The in-situ real-time measurement device for high-frequency pulse laser impact force according to claim 2, characterized in that: The data acquisition system comprises: a signal conditioning module, used to amplify and process the strain electrical signal to generate an amplified strain electrical signal, filter the amplified strain electrical signal to obtain a filtered strain electrical signal, and linearize the filtered strain electrical signal to generate a conditioned strain electrical signal; a first signal processing module, configured to perform digital signal conversion on the conditioned strain electrical signal to generate a converted strain electrical signal, and modulate the converted strain electrical signal to generate the target strain modulation signal; A signal transmitting module is used to transmit the target strain modulation signal to the outside of the selective laser melting SLM device.

4. The in-situ real-time measurement device for high-frequency pulse laser impact force according to claim 1, characterized in that: The oscilloscope comprises: A demodulator, used for demodulating the target strain modulation signal to generate a strain demodulation electrical signal; a second signal processing module, configured to filter and amplify the strain demodulated electrical signal to obtain the final target strain signal; The display unit is used to display the final target strain signal in a preset waveform form.

5. The in-situ real-time measurement device for high-frequency pulse laser impact force according to claim 1, characterized in that: The calculation formula of the pulse laser impact force is: F=σA=EAε=EA(f1-f0) / k(N), P=Eε(Pa), Wherein, σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact region, k is the strain coefficient, f1 is the resonant frequency of the surface acoustic wave strain sensor, and f0 is the initial resonant frequency of the surface acoustic wave strain sensor.

6. A method for in-situ real-time measurement of high-frequency pulse laser impact force, characterized in that: The following steps are involved: Detecting the strain of the preset substrate when the laser impact melts the layer, acquiring a strain electrical signal corresponding to the strain, and performing a preset signal analysis and processing operation on the strain electrical signal to obtain a target strain modulation signal corresponding to the strain electrical signal; receiving the target strain modulation signal, and demodulating the target strain modulation signal to obtain a final target strain signal, and displaying the final target strain signal on a preset oscilloscope screen; The external force applied to the preset surface acoustic wave strain sensor is calculated based on the preset stress-strain relationship and the final target strain signal, so as to calculate the pulsed laser impact force measured in situ and in real time according to the external force.

7. The in-situ real-time measurement method of high-frequency pulse laser impact force according to claim 6 is characterized in that: The calculation formula of the pulse laser impact force is: F=σA=EAε=EA(f1-f0) / k(N), P=Eε(Pa), Wherein, σ is the stress obtained according to the preset stress-strain relationship, E is the elastic modulus of the substrate material, A is the area of ​​the laser impact region, k is the strain coefficient, f1 is the resonant frequency of the surface acoustic wave strain sensor, and f0 is the initial resonant frequency of the surface acoustic wave strain sensor.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement an in-situ real-time measurement method for high-frequency pulse laser impact force as described in any one of claims 6 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement an in-situ real-time measurement method for high-frequency pulse laser impact force as described in any one of claims 6-7.

10. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement an in-situ real-time measurement method for high-frequency pulse laser impact force as described in any one of claims 6-7.

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