Impact mechanical loading device and method based on locked-rotor test of electromagnetic coil emitter

Abstract

The invention relates to a material dynamic mechanical property testing technology, in particular to an impact mechanical loading device and method based on a locked-rotor test of an electromagnetic coil emitter, and the device comprises a pulse power supply module, an electromagnetic loading module, a constraint fixing module and a measurement and control system. Capacitor charging voltage is set through an upper computer, a control switch is switched on to discharge an electromagnetic loading module to generate pulse current, and an electromagnetic coil generates a pulse magnetic field to enable a conductor armature to induce eddy current to generate axial electromagnetic force; the position of the armature is rigidly restrained to form locked rotor, impact electromagnetic force is directly loaded to a sample through an impact head to form impact stress, and dynamic response, fatigue damage and aging accumulation experiments of materials are carried out by monitoring the working performance of a monitoring device such as voltage, current and impact force. The device has the advantages of being small in size, flexible and adjustable in impact stress wavelength and amplitude, high in efficiency and the like, and the problems that a traditional mechanical impact device is large in size, the impact stress pulse width is not easy to regulate and control, and the test efficiency is low are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of dynamic mechanical property testing of materials, and in particular relates to an impact mechanical loading device and method based on a locked-rotor test of an electromagnetic coil transmitter. Background Art

[0002] Traditional impact test equipment mainly includes drop hammer tester and Hopkinson bar. Drop hammer tester can test the impact resistance of materials through free fall impact, and is suitable for evaluating the external impact resistance of engineering materials such as PVC-U pipes and PE sheets. Hopkinson bar device is based on one-dimensional elastic stress wave theory and can achieve 100s -1 ~10000s -1 Dynamic mechanical properties testing within the strain rate range is widely used in mechanical response analysis of materials under load conditions such as dynamic compression, tension and torsion.

[0003] However, traditional impact test equipment has the following limitations: (1) Traditional mechanical impact devices (such as drop hammer and Hopkinson bar) usually rely on heavy mechanical structures and are large in size; (2) The existing kinetic energy impact test equipment based on the principle of electromagnetic launch has the problem that the impact stress pulse width is difficult to control and some of it is too short (μs level). This is mismatched with the ms-level long pulse width stress that the launcher cylinder wall is subjected to in actual electromagnetic launch scenarios, and it is unable to truly simulate the dynamic mechanical response of the cylinder wall material. (3) High repetition frequency fatigue damage testing is limited by the reset efficiency of the mechanical structure and is difficult to meet the high frequency loading test requirements of the cumulative effect of material fatigue.

[0004] Existing electromagnetic emission technologies primarily focus on armature kinetic energy output, but have yet to apply the impact electromagnetic force loading mechanism under stalled-rotor constraints to testing dynamic stress wave responses in materials. Therefore, a new impact testing device with adjustable stress pulse width and amplitude, supporting high-repetition-rate loading, is urgently needed to address the technical limitations of conventional devices in long-pulse load simulation and high-frequency fatigue testing. Summary of the Invention

[0005] The present invention provides an impact mechanics loading device and method based on an electromagnetic coil transmitter stall test. Addressing technical bottlenecks in conventional impact tests in the prior art, such as large structural volume, low repetition rate testing efficiency, and difficulty in regulating stress pulse width, the present invention utilizes a pulsed electromagnetic force loading mechanism to achieve high-precision repetition rate testing of material dynamic response characteristics, fatigue damage evolution, and aging cumulative effects.

[0006] The present invention provides an impact mechanics loading device based on an electromagnetic coil transmitter locked-rotor test, comprising a pulse power supply module 101, an electromagnetic loading module 102, a sample 103, a restraint and fixation module 104, and a measurement and control system 105; the measurement and control module 105 is sequentially connected to the pulse power supply module 101, the electromagnetic loading module 102, and the restraint and fixation module 104, and the sample 103 is placed in the electromagnetic loading module 102; The pulse power supply module 101 includes a pulse capacitor 1011, a closing switch 1012, a charger 1013 and a freewheeling diode 1014, and is used for single or repetitive frequency pulse discharge and continuous oscillation decay pulse discharge; The electromagnetic loading module 102 includes a coil 1021 , a conductor armature 1022 and an impact head 1023 ; The restraint and fixing module 104 includes a front steel frame 1041, a rear steel frame 1042, a horizontal steel plate 1043 and an insulating bottom column 1044, which are used to limit the displacement of the armature; The measurement and control system 105 includes a host computer 1051 , a pressure sensor 1052 , a voltage sensor 1053 and a current sensor 1054 , and is used for monitoring and controlling pulse parameters.

[0007] According to an impact mechanical loading device based on an electromagnetic coil transmitter stall test provided by the present invention, a charger 1013 is connected to both ends of a pulse capacitor 1011 to charge it, and after it reaches the rated voltage, it controls the closed switch 1012 to discharge the coil 1021, and the host computer 1051 realizes the control of the charger 1013.

[0008] According to an impact mechanical loading device based on the electromagnetic coil transmitter stall test provided by the present invention, when the freewheeling diode 1014 is connected in reverse parallel to both ends of the pulse capacitor 1011, a single-peak pulse waveform is formed; if the freewheeling diode 1014 is not connected, a continuous oscillation attenuation pulse waveform is formed.

[0009] According to an impact mechanical loading device based on an electromagnetic coil transmitter stall test provided by the present invention, the bottom of the conductor armature 1022 is raised by an insulating bottom column 1044 and then placed inside the coil 1021; the magnitude of the impact electromagnetic force can be adjusted by adjusting the height of the insulating bottom column 1044. When the bottom surface of the conductor armature 1022 is located in the middle of the coil 1021, the conductor armature 1022 obtains the maximum axial electromagnetic force.

[0010] According to an impact mechanical loading device based on an electromagnetic coil transmitter stall test provided by the present invention, a front steel frame 1041 and a rear steel frame 1042 are vertically fixed to the upper surface of a horizontal steel plate 1043 and locked by bolts, and the distance between the front steel frame 1041 and the rear steel frame 1042 is adjustable; a pressure sensor 1052 is fixed to the inner surface of the front steel frame 1041, and a sample 103 is closely attached to the surface of the pressure sensor 1052, and the impact head 1023 is closely attached to the sample 103 by adjusting the distance between the front and rear steel frames; the inner surface of the rear steel frame 1042 is connected and fixed to the coil 1021 through a bottom flange, which is used to limit the displacement of the coil 1021 during electromagnetic loading.

[0011] According to the present invention, an impact mechanical loading device based on an electromagnetic coil transmitter stall test is provided. The conductor armature 1022 includes a cylinder 1022-1 and a frustum 1022-2. The frustum 1022-2 has a cylindrical groove 1022-3 on its upper surface for accommodating an impact head 1023. The impact head 1023 and the cylindrical groove 1022-3 are connected by an interference fit. The impact head 1023 is made of high-strength steel and includes a round head, a flat head, or other shapes. The round-headed armature consists of a hemisphere 1023-11 with a diameter of d and a cylindrical handle 1023-12 with a bottom diameter of d2 and a height of h. The flat-headed armature consists of a cylinder 1023-21 with a diameter of d and a cylindrical handle 1023-22 with a bottom diameter of d2 and a height of h.

[0012] According to an impact mechanical loading device based on an electromagnetic coil transmitter stall test provided by the present invention, the measurement and control module 105 has a built-in pulse parameter feedback module, a voltage sensor 1053 and a current sensor 1054 for monitoring the voltage amplitude and current waveform, and the pressure sensor 1052 is used to monitor the impact force waveform.

[0013] The present invention also provides an impact mechanical loading method based on an electromagnetic coil transmitter stall test. The method sets a capacitor charging voltage through a host computer 1051, controls the charging and discharging of a pulse power module 101 to generate an instantaneous pulse current, generates a pulse magnetic field through a coil 1021, and causes the conductor armature 1022 to induce eddy currents to generate an axial impact electromagnetic force. The pulse width can be adjusted by changing the capacitance value of the pulse capacitor 1011 and the inductance value of the coil 1021, with a control range of μs to ms. The amplitude can be adjusted by changing the charging voltage value of the pulse capacitor 1011, the armature material and structure, and the axial relative position between the bottom surface of the conductor armature 1022 and the center line of the coil 1021. The conductor armature 1022 is locked in position by a rigid constraint to form a stall. The impact electromagnetic force generated on the conductor armature 1022 is directly loaded onto the sample 103 through the impact head 1023, thereby testing the dynamic response, fatigue damage, and aging accumulation of the material. The specific steps are as follows: S1 determines whether to install a freewheeling diode 1014 according to the type of impact force required for loading; determines the corresponding pulse capacitance, coil inductance, charging voltage and other parameters according to the required impact force pulse width and amplitude; S2 controls the pulse capacitor charging voltage to U 0; After S3 charging is completed, the upper computer 1051 controls the closed switch 1012 to turn on, and the pulse power module 101 discharges to the coil 1021 to generate a pulse current; The S4 conductor armature 1022 induces eddy currents, generating axial electromagnetic force, which is perpendicular to the surface of the sample 103 and closely attached to the sample 103. The electromagnetic force is directly applied to the sample 103 through the impact head 1023; S5 monitors the dynamic mechanical response through the pressure sensor 1052 and displays the impact waveform; S6 stops after single impact loading is completed; S7 repeats S1-S6, and performs periodic repeated impact fatigue loading test by setting the number of loading times and frequency.

[0014] The present invention also provides an electronic device, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the impact mechanics loading method based on the electromagnetic coil transmitter locked-rotor test.

[0015] The present invention also provides a computer-readable storage medium having a computer program / instruction stored thereon. When the computer program / instruction is executed by a processor, the steps of the impact mechanical loading method based on the electromagnetic coil transmitter locked-rotor test are implemented.

[0016] The present invention also provides an electronic device, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the pulse electromagnetic force loading method based on the electromagnetic stall principle.

[0017] The present invention also provides a computer-readable storage medium having a computer program / instruction stored thereon. When the computer program / instruction is executed by a processor, the steps of the impact mechanical loading method based on the electromagnetic coil transmitter locked-rotor test are implemented.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes an impact mechanical loading device based on the electromagnetic coil transmitter stall test, which can be used in the field of dynamic mechanical property testing technology of materials, and provides a more efficient method for in-depth research on dynamic impact, damage and aging accumulation of materials. This method realizes dynamic mechanical loading with flexible controllable pulse stress waveform, significantly improving test efficiency and data reliability. It is flexible and adjustable, supporting single high-energy impact (such as explosion simulation) and high-frequency repeated loading (fatigue damage research); the device converts pulse electromagnetic energy directly into internal stress waves of the specimen by rigidly constraining the armature displacement, thereby realizing dynamic mechanical testing. The conductor armature and the impact head support rapid replacement and adapt to different test scenarios; at the same time, the modular design and control meet the needs of various actual working conditions. The device of the present invention is suitable for the testing needs of composite materials, metal alloys, polymer materials, etc. in the study of high strain rate impact, fatigue damage and aging accumulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a schematic diagram of the module connection relationship of the impact mechanical loading device with freewheeling diodes based on the electromagnetic coil transmitter locked-rotor test provided by an embodiment of the present invention; Figure 2 This is a schematic diagram of the connection relationship of the modules of the impact mechanical loading device based on the electromagnetic coil transmitter locked-rotor test provided by an embodiment of the present invention, which are not connected to the freewheeling diode; Figure 3 1 is a schematic diagram of a specific physical model of the electromagnetic loading module 102 and the constraint fixing module 104 provided in an embodiment of the present invention; Figure 4 10 is a schematic diagram of a separate structure of a conductor armature 1022 and an impact head 1023 provided in an embodiment of the present invention; Figure 5 3. A comparison diagram of electromagnetic force waveforms of electromagnetic locked-rotor pulses under different excitation voltage settings when the capacitance value is fixed, provided by an embodiment of the present invention; Figure 6 This is a comparison diagram of the magnetic locked-rotor pulse electromagnetic force waveforms under different capacitance settings when the excitation voltage value is fixed, provided by an embodiment of the present invention; Figure 7 This is a waveform diagram of the electromagnetic force oscillation attenuation of an electromagnetic locked-rotor pulse under certain capacitance and excitation voltage settings provided by an embodiment of the present invention; Figure 8It is a structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0022] like Figure 1 As shown, this embodiment is implemented through the following technical solutions: an impact mechanical loading device based on an electromagnetic coil transmitter locked-rotor test, comprising a measurement and control module 105, a pulse power module 101, an electromagnetic loading module 102, a specimen 103, and a restraint and fixation module 104, which are connected in sequence. The measurement and control module 105 is connected in sequence to the pulse power module 101, the electromagnetic loading module 102, and the restraint and fixation module 104, and the specimen 103 is placed in the electromagnetic loading module 102.

[0023] The pulse power supply module 101 includes a pulse capacitor 1011, a closing switch 1012, a charger 1013 and a freewheeling diode 1014, which are used for single or repetitive frequency pulse discharge; The electromagnetic loading module 102 includes a coil 1021 , a conductor armature 1022 and an impact head 1023 ; The restraint and fixing module 104 includes a front steel frame 1041, a rear steel frame 1042, a horizontal steel plate 1043 and an insulating bottom column 1044, which are used to limit the displacement of the armature; The measurement and control system 105 includes a host computer 1051, a pressure sensor 1052, a voltage sensor 1053 and a current sensor 1054, which are used for pulse parameter monitoring and control.

[0024] The device sets the capacitor charging voltage through the host computer 1051, controls the charging and discharging of the pulse power supply module 101 to generate instantaneous pulse current, and the electromagnetic coil generates an alternating magnetic field, so that the conductor armature 1022 induces eddy current to generate axial impact electromagnetic force; the position of the conductor armature 1022 is locked by rigid constraints to form a stalled rotor, and the impact electromagnetic force generated on the armature is loaded to the sample 103 through the impact head, realizing high-precision testing of material dynamic response, fatigue damage and aging accumulation.

[0025] The charger 1013 is connected to both ends of the pulse capacitor 1011 to charge it. After the rated voltage is reached, the closed switch 1012 is controlled to conduct to discharge the coil 1021. The host computer 1051 is connected to the charger 1013 to realize the control of the charger 1013.

[0026] like Figure 1 、 Figure 2 As shown, when the freewheeling diode 1014 is connected in reverse parallel to the two ends of the pulse capacitor 1011, a single peak pulse waveform is formed. If the freewheeling diode 1014 is not connected, a continuous oscillation decay pulse waveform is formed.

[0027] like Figure 3 As shown, the bottom of the conductive armature 1022 is elevated by an insulating bottom column 1044 and then placed inside the coil 1021 to form a coil transmitter. The coil transmitter is then cast and encapsulated using a resin material. The height of the insulating bottom column 1044 is selected based on the height of the coil 1021. When the bottom surface of the conductive armature 1022 is located exactly in the center of the coil 1021, the optimal electromagnetic induction level can be achieved, and the conductive armature 1022 obtains the maximum axial electromagnetic force.

[0028] The conductor armature 1022 and the impact head 1023 adopt a split anti-fatigue structure, such as Figure 4 As shown, the conductor armature 1022 is generally composed of a cylindrical body 1022-1 and a frustum 1022-2. The upper surface of the frustum 1022-2 is provided with a cylindrical recess 1022-3 with a diameter d1 and a depth h, which accommodates the impact head 1023. The impact head 1023 is machined from high-strength steel and can include a flat head, a round head, or other shapes. The round-headed armature consists of a hemisphere 1023-11 with a diameter d and a cylindrical shank 1023-12 with a bottom diameter d2 and a height h. The flat-headed armature consists of a cylinder 1023-21 with a diameter d and a cylindrical shank 1023-22 with a bottom diameter d2 and a height h. The front-end impact head 1023 and the cylindrical recess 1022-3 of the conductor armature 1022 have an interference fit, with d1 slightly greater than d2.

[0029] The coil launcher's base is fixed to the rear steel frame 1042, while the impact head 1023 is constrained by the front steel frame 1041. The front and rear steel frames 1041 and 1042 are bolted to a horizontal steel plate 1043, forming a rigid framework that enables precise positioning and load transfer of the electromagnetic loading module 102. Furthermore, the spacing between the front and rear steel frames 1041 and 1042 is adjustable. A pressure sensor 1052 is fixed to the inner surface of the front steel frame 1041, with the specimen 103 in close contact with the surface of the pressure sensor 1052. The spacing between the front and rear steel frames is adjusted to ensure that the impact head 1023 is in close contact with the specimen 103. The inner surface of the rear steel frame 1042 is connected to the coil 1021 via a bottom flange, limiting displacement of the coil launcher during electromagnetic loading.

[0030] The impact head 1023 and the sample 103 should be in close contact to prevent a gap from being generated due to a lack of close contact, which would cause a slight acceleration movement of the armature in the axial direction during pulse discharge, resulting in mechanical vibration and unconcentrated transmission of stress waves.

[0031] The surface of the high-strength steel impact head 1023 is nitrided to greatly increase the hardness and significantly reduce the wear rate of a single impact.

[0032] The core innovations of this invention include the following modules and technical details: 1. Electromagnetic stress wave loading mechanism: By rigidly constraining the armature to lock its position and create a stall, the pulsed electromagnetic energy is directly converted into stress waves within the specimen, eliminating the interference of traditional kinetic energy impact. For example, during a single pulse loading, the peak pressure at the armature head can reach 1000 MPa.

[0033] 2. Waveform parameters can be flexibly adjusted: Pulse parameters such as pulse width can be adjusted by changing the parameters of the external RLC circuit, with a control range of μs~ms. The voltage, frequency and number of repetitions can also be controlled by the host computer to achieve single high-energy impact or high-frequency periodic loading, with high test efficiency. For example, when setting U=1kV and capacitance C=4mF, the single pulse energy E=0.5CU 2 =2J, and repeated loading 10 times can simulate the cumulative damage.

[0034] 3. Separate design of conductor armature and impact head: The high-strength steel impact force transmission head has high yield strength and hardness to ensure resistance to plastic deformation under impact load; the conductive substrate can be selected from metals with high electrical conductivity and high thermal conductivity to optimize eddy current generation efficiency while taking into account heat dissipation.

[0035] 4. Waveform switching of the freewheeling diode dual-mode operation: When the freewheeling diode is connected, a single-peak pulse wave can be generated; when the freewheeling diode is removed, the pulse current in the RLC circuit is underdamped and oscillates to generate a continuous attenuated oscillation wave. This mode is particularly suitable for fatigue damage testing of highly elastomeric polymers such as rubber, matching the relaxation time and simulating actual vibration conditions.

[0036] Example Glass fiber / epoxy resin composite material was used as the test object to verify the dynamic response and damage characteristics of the device under a preset number of electromagnetic pulse loadings.

[0037] Step 1: Initial circuit line connection steps for each module, such as Figure 1 shown.

[0038] Specifically, the input end of the charger 1013 is connected to a three-phase 380V industrial power supply, and the high-voltage terminal of the output end is connected to the positive pole of the pulse capacitor 1011 through a cable; the low-voltage end of the pulse capacitor 1011 is grounded through a closed switch 1012, and the switch signal line is connected to the PWM control port of the host computer 1051; a freewheeling diode 1014 is connected in parallel to the high-voltage end of the pulse capacitor 1011 to suppress reverse current.

[0039] Step 2: The installation and positioning adjustment steps of the sample 103 in the electromagnetic loading module 102 and the constraint fixing module 104, such as Figure 3 shown.

[0040] Specifically, glass fiber / epoxy resin laminate specimens were prepared with a 0° / 90° layup, an 80 mm diameter circle, and a thickness of 2 mm. After cutting and polishing, the edges were chamfered by 0.5 mm to avoid stress concentration; Figure 3 As shown, the sample 103 is placed in the circular sample groove 1044, the insulating bottom column 1044 is placed in the coil 1021, and then the conductor armature 1022 is placed in the coil 1021. The front steel frame with the sample is moved until the surface of the sample is close to the impact head 1023. The inner side of the rear steel frame 1042 is provided with a coil 1021 mounting seat, and the bottom of the coil 1021 is fixed by a flange connection. All fixing devices are placed together on the horizontal steel plate 1043 to ensure that the front steel frame 1041 and the coil 1021 are horizontally coaxial and collinear. The limiting holes are fixed with bolts to ensure the rigid connection of the device.

[0041] Step 3: Electromagnetic pulse parameter setting and loading execution steps.

[0042] Specifically, the host computer 1051 inputs target parameters and can set different capacitor voltages U0. For example, setting the capacitor voltage U0 = 1.5kV. When the RLC circuit parameters are C = 4mF, L = 63μH, and R = 16mΩ, the time it takes for the pulse to complete a complete rise and fall process is about 3ms. The actual pulse width can be adjusted according to the RLC circuit parameters to obtain pulses with different pulse widths. The cycle loading mode is set, and the number of loading times depends on the specific test requirements. This embodiment takes 50 loading times as an example. When the host computer 1051 clicks the "Start" button, the charger 1013 charges the pulse capacitor 1011, displaying the charging voltage and current curve in real time. The voltage across the pulse capacitor 1011 is also displayed in real time. After charging is complete, the system triggers an automatic stop indication and actively triggers the closing switch 1012, discharging the pulse capacitor 1011 through the coil 1021. The oscilloscope records the pulse current peak value of approximately 8kA and the waveform.

[0043] The conductor armature 1022 induces eddy currents to generate axial electromagnetic force, which is sampled by the pressure sensor, recording a peak electromagnetic force of approximately 18 kN and a waveform. The conductor armature 1022 and the impact head 1023 are constrained by the rigid base column and the front and rear steel frames, and their positions are locked. The electromagnetic energy is converted into a stress wave of the specimen.

[0044] In addition, the specific implementation also includes, for example Figure 2 As shown in the figure, when the freewheeling diode is not connected to the circuit, the pulse current forms an underdamped oscillation in the RLC circuit. When the capacitance of the pulse capacitor is set to 4mF and the excitation voltage is set to 1500V, the following is generated: Figure 7 The continuous damping oscillation wave shown in the figure has multiple complete oscillation cycles, which causes the specimen to undergo multiple cycles of stress within a single loading, simulating actual vibration conditions.

[0045] In addition, in the specific implementation, the same operation method was used to conduct comparative tests with different excitation voltages and different capacitance values. Figure 5 This is a comparison diagram of the impact electromagnetic force waveform under different excitation voltage settings when the capacitance value of this embodiment is fixed. Figure 6 The following diagram compares the impact electromagnetic force waveforms for different capacitance settings when the excitation voltage is fixed. The pulse width is defined using the commonly used full-width at half maximum (FWHM) model, which is the time interval from the electromagnetic force rising from 50% of its peak value to its peak value and then falling back to 50% of its peak value.

[0046] Under the condition of fixed capacitance and other circuit parameters, the voltage and peak electromagnetic force have a positive correlation. When the voltage increases from 500V to 1500V, the peak electromagnetic force increases from 8kN to 18kN, and the pulse width is consistent. The full width at half maximum (FWHM) of the pulse width at different voltages remains at 0.6ms, indicating that the pulse width is dominated by the capacitance and circuit parameters and is independent of the voltage.

[0047] With fixed excitation voltage and other circuit parameters, the capacitance values ​​were 1mF, 4mF, and 10mF, respectively, and the pulse width (FWHM) was extended from 400μs to 1ms, demonstrating a positive correlation between pulse width and capacitance. By adjusting the circuit coil inductance, the pulse width can be precisely controlled from μs to ms, matching the actual stress duration of the electromagnetic transmitter barrel wall and providing realistic loading conditions for material fatigue damage research.

[0048] Step 4: Termination of dynamic impact loading experiment and test and analysis of specimen results.

[0049] Specifically, the experiment is stopped after the set number of stall loading times is reached, the bleeder resistor is connected to the capacitor terminal, the voltage drops to a safe range within 3 seconds, the high-frequency charger is turned off, the power supply is turned off, and the circuit connection is disconnected.

[0050] The surface condition of the sample can be observed macroscopically. A small area of ​​depression with a diameter of about 3~4mm appears. The area turns white and there is no delamination. The average impact strength test value is 40kJ / m 2 , the scanning electron microscope (SEM) can be used to observe the microstructure of the impact zone, fiber fracture, and matrix debonding.

[0051] This example demonstrates the complete process of an electromagnetic stall test device, from system initialization, specimen installation, parameter setting, dynamic loading, to damage assessment, by setting electromagnetic pulse loading at different capacitor voltages. This example demonstrates the efficiency and accuracy of this invention in current dynamic mechanical testing of materials and lays a technical foundation for further research into complex operating conditions such as high-frequency fatigue and multi-pulse superposition.

[0052] This embodiment also provides an impact mechanical loading method based on an electromagnetic coil transmitter stall test, which is applicable to an impact mechanical loading device based on an electromagnetic coil transmitter stall test. This method sets the capacitor charging voltage via the host computer 1051, controls the charging and discharging of the pulse power module 101 to generate an instantaneous pulse current, generates a pulse magnetic field via the coil 1021, and causes the conductor armature 1022 to induce eddy currents to generate an axial impact electromagnetic force. The pulse width can be adjusted by changing the capacitance value of the pulse capacitor 1011 and the inductance value of the coil 1021, with a control range of μs to ms. The amplitude can be adjusted by changing the charging voltage value of the pulse capacitor 1011, the armature material and structure, and the axial relative position between the bottom surface of the conductor armature 1022 and the center line of the coil 1021. The conductor armature 1022 is locked in position by a rigid constraint to form a stall. The impact electromagnetic force generated on the conductor armature 1022 is directly loaded onto the specimen 103 via the impact head 1023, thereby testing the material's dynamic response, fatigue damage, and aging accumulation. The specific steps are as follows: S1 determines whether to install a freewheeling diode 1014 according to the type of impact force required for loading; determines the corresponding pulse capacitance, coil inductance, charging voltage and other parameters according to the required impact force pulse width and amplitude; S2 controls the pulse capacitor charging voltage to U 0; After S3 charging is completed, the upper computer 1051 controls the closed switch 1012 to turn on, and the pulse power module 101 discharges to the coil 1021 to generate a pulse current; The S4 conductor armature 1022 induces eddy currents, generating axial electromagnetic force, which is perpendicular to the surface of the sample 103 and closely attached to the sample 103. The electromagnetic force is directly applied to the sample 103 through the impact head 1023; S5 monitors the impact force waveform via pressure sensor 1052; S6 stops after single impact loading is completed; S7 repeats S1-S6. By setting the number of loading times and frequency, periodic repetitive impact loading tests can be performed.

[0053] Figure 8 An example of a physical structure diagram of an electronic device is shown below. Figure 8As shown, the electronic device may include: a processor, a communications interface, a memory, and a communications bus, wherein the processor, the communications interface, and the memory communicate with each other via the communications bus. The processor may invoke logic instructions in the memory to execute an impact mechanical loading method based on a locked-rotor test of an electromagnetic coil transmitter.

[0054] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage media include various media capable of storing program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0055] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the impact mechanical loading method based on the electromagnetic coil transmitter stall test provided by the above methods.

[0056] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0057] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An impact mechanics loading device based on electromagnetic coil launcher locked rotor test, characterized in that: The apparatus comprises a pulse power supply module (101), an electromagnetic loading module (102), a sample (103), a constraint fixing module (104), and a measurement and control system (105); the measurement and control module (105) is sequentially connected to the pulse power supply module (101), the electromagnetic loading module (102), and the constraint fixing module (104); and the sample (103) is placed in the electromagnetic loading module (102); The pulse power supply module (101) comprises a pulse capacitor (1011), a closing switch (1012), a charger (1013) and a freewheeling diode (1014), and is used for single or repetitive frequency pulse discharge and continuous oscillation attenuated pulse discharge; The electromagnetic loading module (102) comprises a coil (1021), a conductor armature (1022), and an impact head (1023); The restraint and fixing module (104) comprises a front steel frame (1041), a rear steel frame (1042), a horizontal steel plate (1043) and an insulating bottom column (1044), and is used to limit the displacement of the armature; The measurement and control system (105) includes a host computer (1051), a pressure sensor (1052), a voltage sensor (1053) and a current sensor (1054), and is used for monitoring and controlling pulse parameters.

2. The impact mechanical loading device based on the electromagnetic coil launcher locked-rotor test according to claim 1 is characterized in that: The charger (1013) is connected to both ends of the pulse capacitor (1011) to charge it. After the rated voltage is reached, the charger (1013) is controlled to close the switch (1012) to discharge the coil (1021). The upper computer (1051) controls the charger (1013).

3. The impact mechanical loading device based on the electromagnetic coil launcher locked-rotor test according to claim 1 is characterized in that: When the freewheeling diode (1014) is connected in reverse parallel to both ends of the pulse capacitor (1011), a single-peak pulse waveform is formed; if the freewheeling diode (1014) is not connected, a continuous oscillation attenuation pulse waveform is formed.

4. The impact mechanical loading device based on the electromagnetic coil launcher locked-rotor test according to claim 1 is characterized in that: The bottom of the conductor armature (1022) is raised by an insulating bottom column (1044) and then placed in the coil (1021); the magnitude of the impact electromagnetic force can be adjusted by adjusting the height of the insulating bottom column (1044).

5. The impact mechanical loading device based on the electromagnetic coil launcher locked-rotor test according to claim 1, characterized in that: The front steel frame (1041) and the rear steel frame (1042) are vertically fixed to the upper surface of the horizontal steel plate (1043) and locked by bolts, and the distance between the front steel frame (1041) and the rear steel frame (1042) is adjustable; the pressure sensor (1052) is fixed on the inner surface of the front steel frame (1041), and the sample (103) is closely attached to the surface of the pressure sensor (1052). The distance between the front and rear steel frames is adjusted to ensure that the impact head (1023) is closely attached to the sample (103); the inner surface of the rear steel frame (1042) and the coil (1021) are connected and fixed via a bottom flange, which is used to limit the displacement of the coil (1021) during electromagnetic loading.

6. The impact mechanical loading device based on the electromagnetic coil launcher locked-rotor test according to claim 1, characterized in that: The conductor armature (1022) comprises a cylinder (1022-1) and a truncated cone (1022-2); a cylindrical groove (1022-3) is formed on the upper surface of the truncated cone (1022-2) for accommodating an impact head (1023); the impact head (1023) and the cylindrical groove (1022-3) are connected by interference fit; the impact head (1023) is made of high-strength steel and has a round head, a flat head, or other shapes; the round-head armature comprises a hemisphere (1023-11) with a diameter of d and a cylindrical handle (1023-12) with a bottom diameter of d2 and a height of h; the flat-head armature comprises a cylinder (1023-21) with a diameter of d and a cylindrical handle (1023-22) with a bottom diameter of d2 and a height of h.

7. The impact mechanical loading device based on the electromagnetic coil launcher locked-rotor test according to claim 1, characterized in that: The measurement and control module (105) has a built-in pulse parameter feedback module, a voltage sensor (1053) and a current sensor (1054) for monitoring the voltage amplitude and current waveform, and a pressure sensor (1052) for monitoring the impact force waveform.

8. An impact mechanics loading method based on electromagnetic coil launcher locked rotor test, characterized in that: The invention is applicable to the impact mechanical loading device based on the electromagnetic coil transmitter stall test as described in any one of claims 1 to 7. The method sets the capacitor charging voltage through the host computer (1051), controls the charging and discharging of the pulse power module (101) to generate an instantaneous pulse current, generates a pulse magnetic field through the coil (1021), and causes the conductor armature (1022) to induce eddy current to generate an axial impact electromagnetic force. The pulse width can be adjusted by changing the capacitance value of the pulse capacitor (1011) and the inductance value of the coil (1021), and the control range is μ The amplitude can be adjusted by changing the charging voltage value of the pulse capacitor (1011), the armature material and structure, and the axial relative position between the bottom surface of the conductor armature (1022) and the center line of the coil (1021); the position of the conductor armature (1022) is locked by rigid constraint to form a stalled rotor, and the impact electromagnetic force generated on the conductor armature (1022) is directly loaded onto the sample (103) through the impact head (1023), thereby realizing the test of the dynamic response, fatigue damage and aging accumulation of the material; the specific steps are as follows: S1 determines whether to install a freewheeling diode (1014) according to the type of impact force required for loading; and determines corresponding parameters such as pulse capacitance, coil inductance, and charging voltage according to the required impact force pulse width and amplitude; S2 controls the pulse capacitor charging voltage to U 0; After S3 is charged, the upper computer (1051) controls the closed switch (1012) to be turned on, and the pulse power module (101) discharges to the coil (1021), generating a pulse current; The S4 conductor armature (1022) induces eddy currents, generating an axial electromagnetic force, the direction of which is perpendicular to the surface of the sample (103) and closely attached to the sample (103), and the electromagnetic force is directly loaded onto the sample (103) through the impact head (1023); S5 monitors the impact force waveform via a pressure sensor (1052); S6 stops after single impact loading is completed; S7 repeats S1-S6. By setting the number of loading times and frequency, periodic repetitive impact loading tests can be performed.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to claim 8.

10. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to claim 8 are implemented.

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