Impact toughness experimental device and method for pulsed magnetic field force loading

Abstract

The invention provides a pulsed magnetic field force loaded impact toughness experimental device and method, a power system of the device adopts pulsed magnetic field force, and the principle of the pulsed magnetic field force is the same as that of electromagnetic forming in high-energy-rate forming. Compared with a free falling motion form of a Charpy pendulum bob testing machine, the device adopts the pulsed magnetic field force as a power source, so that the experiment efficiency can be greatly improved, and the device is small in size, flexible to operate, stable in test quality and high in efficiency, impacts and loads a sample at a high speed, simplifies the experiment operation, and is easier to realize semi-automatic and full-automatic operation.

Description

Technical Field

[0001] The invention relates to the technical field of material mechanical property detection, in particular to an impact toughness test device and method loaded with pulse magnetic field force. Background Art

[0002] In addition to sufficient strength and plasticity, metal materials are also required to have sufficient toughness during use. Toughness refers to the ability of a material to absorb energy during elastic deformation, plastic deformation and fracture.

[0003] The Charpy impact test measures the toughness of materials under impact load and multi-axial stress. The Charpy impact test is to place a specimen with a specified shape, size and notch type on the specimen support of the impact tester so that it is in a simply supported beam state. Then a pendulum of a specified height is used to strike the specimen once. In essence, the energy conversion process is used to measure the work absorbed by the specimen when it breaks under this impact.

[0004] The pulse magnetic field force forms a discharge loop between the capacitor and the control switch. The instantaneous current generates a strong magnetic field through the working coil, and uses electromagnetic induction to generate a high-energy Lorentz force on the surface of the metal material, while generating induced current and magnetic field in the metal workpiece.

[0005] The traditional Charpy pendulum test uses the kinetic energy generated by the pendulum being dropped from a height to test the impact toughness of the sample. The present invention is based on the application of pulsed magnetic field force in the field of impact toughness test, and is improved to perform the impact toughness test under electromagnetic force drive. Compared with the traditional Charpy pendulum test equipment, the present invention is more compact and simple. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide an impact toughness test device and method loaded with pulse magnetic field force, aiming to improve the problems of traditional material impact toughness test equipment, which is complicated to operate, large and bulky, low efficiency and difficult to realize automation. By improving the source of impact force, the impact toughness test experiment is simple and quick to operate, and the operation process of traditional equipment is improved, making the equipment operation more convenient and quick, improving the test efficiency, and facilitating semi-automation and automation.

[0007] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an impact toughness test device loaded with pulse magnetic field force, comprising a combined unit assembly, an impact assembly, a flat coil assembly, a sample fixing assembly and a control system assembly; the combined unit assembly comprises a support screw, an upper seat plate, a middle seat plate, a lower seat plate, an upper shell plate, a middle shell protective cover, a right shell plate, a left shell plate, a front shell plate, a rear shell plate, a support column, a bolt and a nut; the impact assembly is arranged between the upper shell plate and the sample fixing assembly, and the impact assembly comprises a guide sleeve, a drive plate, an insulating lining plate, a punch rod, a punch bolt, a V-shaped hammer head, a reset spring and an amplifier; the flat coil assembly is arranged between the guide sleeve and the insulating lining plate, and the flat coil assembly comprises a flat coil frame and a flat coil; the sample fixing assembly is located on the lower seat plate, and the sample fixing assembly comprises a push screw, a push clamp, a test support block and a sample; the control system assembly comprises an operation panel, a telescopic support arm, a laser velocimeter and a discharge system.

[0008] In a preferred embodiment, the left shell plate, the right shell plate, the upper seat plate and the lower seat plate are integrally formed parts, the left shell plate and the right shell plate are provided with slots, and the middle seat plate passes through the slots and is placed on the left shell plate and the right shell plate.

[0009] In a preferred embodiment, the impact assembly includes a guide sleeve fixed to the lower surface of the upper shell plate, the guide sleeve is connected to the upper shell plate through supporting bolts, and the lower surface of the guide sleeve is connected to the lower seat plate; a through hole is opened in the center of the lower seat plate, and the guide sleeve is aligned with the edge of the through hole.

[0010] In a preferred embodiment, the flat coil assembly is fixed in a guide sleeve, and a notch is provided on one side of the guide sleeve so that the side of the flat coil assembly connected to the external circuit can be placed in the guide sleeve;

[0011] The middle shell protective sleeve is located below the guide sleeve and above the upper seat plate; the middle shell protective sleeve is provided with a through hole for connecting the flat coil assembly wire to an external circuit.

[0012] In a preferred embodiment, the impact assembly includes the guide sleeve, a driving plate and an insulating lining plate that can move up and down along the inner wall of the guide sleeve are installed below the flat coil assembly, an amplifier is fixedly connected to the lower surface of the insulating lining plate, a punch bar is fixedly connected to the lower end of the amplifier, a V-shaped hammer head is fixedly connected to the lower side of the punch bar through a punch bolt, and the impact assembly and the flat coil assembly are located on the same central axis;

[0013] The driving plate is made of red copper, and the amplifier is a conical column shape that is larger at the top and smaller at the bottom, with the side close to the driving plate being larger and the part connected to the punch rod being smaller.

[0014] In a preferred embodiment, the flat coil assembly is composed of a flat coil frame and a flat coil, the flat coil frame is made of epoxy resin, and the flat coil is wound by a copper wire along the flat coil frame and embedded in the flat coil frame, so that the outermost turn of the copper wire can fit closely to the outer wall of the bakelite frame;

[0015] The copper conductor is made of a copper strip, and an insulating tape with high compressive strength is wrapped around the copper strip to achieve electrical insulation between the turns. The flat coil assembly converts electrical energy into the impact force of the impact assembly, and the flat coil circuit is connected to an external circuit.

[0016] An insulating lining is placed on the flat coil assembly, and the insulating lining material is an insulating material such as rubber.

[0017] In a preferred embodiment, the lower seat plate is fixedly connected to the sample fixing assembly and has a slide groove, the two side push clamps are respectively placed in the slide groove, the left shell plate and the right shell plate are respectively provided with threaded holes, the two side push screws are respectively fixed to the left shell plate and the right shell plate, the sample support block is placed on the push clamp, and the sample support block has a notch for preventing the sample;

[0018] A laser speed meter is fixed on the lower seat plate to measure the speed of the V-shaped hammer after the impact is completed.

[0019] In a preferred embodiment, the guide sleeve and the amplifier are above the upper seat plate, a through hole is opened in the center of the middle seat plate, the oil-free lubricating sleeve is placed in the central through hole of the middle seat plate, the punch rod passes through the oil-free lubricating sleeve and the middle seat plate, the reset spring is located above the oil-free lubricating sleeve and coincides with its axis, the punch rod passes through the reset spring, and the reset spring can reset the impact assembly after each discharge on the one hand, and play a buffering role between the middle die seat plate and the impact unit on the other hand to prevent the amplifier from colliding with the middle die seat plate.

[0020] In a preferred embodiment, the support column is fixed to the lower seat plate by bolts, and there are four support columns respectively located at the four corners of the lower seat plate;

[0021] The telescopic support arm is fixedly connected to the upper seat plate, the operation panel is fixedly connected to the end of the telescopic support arm, and the discharge system and the laser tester are respectively connected to the operation panel for control.

[0022] The present invention also provides an impact toughness test method for pulse magnetic field force loading, which adopts the above-mentioned impact toughness test device for pulse magnetic field force loading: placing the prepared sample on the sample support platform, then adjusting the advancing screw and the advancing clamping plate to place the sample on the central axis; closing the charging switch through the operation panel to connect the charging circuit composed of the rectifier A, the current limiting resistor R and the capacitor group C; the 380V power supply charges the capacitor group C through the charging circuit, and when the charging is completed, the charging switch is disconnected through the operation panel to cut off the charging circuit; then the high-voltage pulse generator is controlled through the operation panel to generate a high-voltage pulse, triggering the high-frequency thyristor discharge switch to turn on the capacitor group C. The discharge circuit composed of capacitor group C and flat coil assembly; since capacitor group C and the coil constitute a typical RLC circuit, the discharge current passing through the flat coil has the characteristic of attenuated oscillation. According to the law of electromagnetic induction, the current generates an induced current in the high-conductivity driving plate adjacent to it, and the latter generates an induced magnetic field; thus, the coil current magnetic field and the induced current magnetic field are superimposed and enhanced in the gap between the flat coil assembly and the driving disk; the enhanced magnetic field and the induced current of the driving plate cause the driving plate to be subjected to an axially downward pulse load, which is then amplified by the amplifier and acts on the sample through the punch rod and the V-shaped hammer head, realizing the experimental process of the impact toughness test.

[0023] Compared with the prior art, the present invention has the following beneficial effects: the present invention provides an impact toughness test device loaded with pulse magnetic field force, the power system of the device adopts pulse magnetic field force, and uses flat coil components and impact components to convert electrical energy into impact force of impact specimens, which is the same as the principle of electromagnetic forming in high energy rate forming, belongs to impact loading, has a high loading rate, and the test fracture time is extremely short, generally in microseconds; and with the help of electromagnetic force loading, it can cope with different specimens and provide different impact energies for adjustment, realizing precise variable control of impact energy; compared with the free fall motion form of Charpy pendulum tester, the present device adopts pulse magnetic field force as power source, which can greatly improve the experimental efficiency, and the present device is small in size, flexible in operation, high-rate impact loading specimens, good in repeatability, stable in test quality, high in efficiency, and simple in experimental operation, and semi-automatic and fully automatic operations are also easier to achieve. Therefore, the present invention has strong practicality and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the main cross-sectional structure of part of the device of the present invention;

[0025] Figure 2 It is a schematic diagram of the three-dimensional structure of the device of the present invention;

[0026] Figure 3 It is a schematic diagram of the assembly of the flat coil assembly structure and the impact assembly of the device of the present invention;

[0027] Figure 4 It is a schematic diagram of the assembly of the sample fixing assembly of the device of the present invention;

[0028] Figure 5 It is a schematic diagram of the assembly of the flat coil assembly of the device of the present invention;

[0029] Figure 6 is a control circuit block diagram of the device of the present invention;

[0030] In the figure:

[0031] 1-support screw; 2-guide sleeve; 3-flat coil skeleton; 4-flat coil; 5-drive plate; 6-middle shell protective cover; 7-punch rod; 8-upper seat plate; 9-punch bolt; 10-middle seat plate; 11-right shell plate; 12-advance screw; 13-support column; 14-sample; 15-V-shaped hammer; 16-sample support block; 17-lower seat plate; 18-advance splint; 19-left shell plate; 20-oil-free lubricating sleeve; 21-sleeve bolt; 22-reset spring; 23-amplifier; 24-insulating lining; 25-upper shell plate; 26-telescopic support arm; 27-operation panel; 28-laser velocimeter. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0035] like Figure 1-6As shown, this embodiment provides an impact toughness test device loaded with pulse magnetic field force, including a combined unit component, an impact component, a flat coil component, a sample fixing component and a control system component. The combined unit includes a support screw 1, an upper base plate 8, a middle base plate 10, a lower base plate 17, an upper shell plate 25, a middle shell protective cover 6, a right shell plate 11, a left shell plate 19, a support column 13, bolts and nuts, so that each unit is connected into an organic whole to smoothly and reliably complete the test process; the impact component is arranged between the upper shell plate 25 and the sample fixing component, and the impact component It includes a guide sleeve 2, a drive plate 5, an insulating lining 24, a punch rod 7, a punch bolt 9, a V-shaped hammer head 15, a reset spring 22, and an amplifier 23; the flat coil assembly is arranged between the guide sleeve 2 and the insulating lining 24, and the flat coil assembly includes a flat coil skeleton 3 and a flat coil 4; the sample fixing assembly is located on the lower seat plate 17, and the sample fixing assembly includes a push screw 12, a push clamp 18, a test support block 16 and a sample 14; the control system assembly includes an operation panel 27, a telescopic support arm 26, a laser velocimeter 28, and a discharge system.

[0036] In this embodiment, the left shell plate 19, the right shell plate 11, the upper seat plate 8 and the lower seat plate 17 are integrally formed parts, and the left shell plate 19 and the right shell plate 11 are provided with slots, and the middle seat plate 10 is placed on the left shell plate 19 and the right shell plate 11 through the slots; the guide sleeve 2 is connected to the upper shell plate 25 by the support bolt 1, and the lower surface of the guide sleeve 2 is connected to the lower seat plate 8; the middle shell protective sleeve 6 is located below the guide sleeve 2 and above the upper seat plate 8, and the middle shell protective sleeve 6 is provided with a through hole for connecting the flat coil assembly wire to the external circuit; the impact assembly includes the guide sleeve 2, and the flat coil assembly is provided with a driving plate 5 and an insulating lining 24 that can move up and down along the inner wall of the guide sleeve 2, and the lower surface of the insulating lining 24 is fixedly connected with an amplifier 23, and the guide The sleeve 2 and the amplifier 23 are above the upper seat plate 8. A through hole is provided at the center of the middle seat plate 10. The oil-free lubricating sleeve 20 is placed in the central through hole of the middle seat plate 10. The punch rod 7 passes through the oil-free lubricating sleeve 20 and the middle seat plate 10. The reset spring 22 is located above the oil-free lubricating sleeve 20 and coincides with its axis. The punch rod 7 passes through the reset spring 22. The reset spring 22 can reset the impact assembly after each discharge, and on the other hand, it plays a buffering role between the middle seat plate 10 and the impact unit to prevent the amplifier 23 from colliding with the middle seat plate 10. The telescopic support arm 26 is fixedly connected to the upper seat plate 8. The operation panel 27 is fixedly connected to the end of the telescopic support arm 26. The discharge system and the laser tester 28 are respectively connected to the operation panel 27 for control.

[0037] like Figure 3As shown, in this embodiment, the driving plate 5 is made of copper, the amplifier 23 is a conical column with a large upper part and a small lower part, the side close to the driving plate 5 is large, and the connection with the punch rod 7 is small; the lower end of the amplifier 23 is fixedly connected to the punch rod 7, and the V-shaped hammer head 15 is fixedly connected to the lower part of the punch rod 7 through the punch bolt 9, and the impact assembly and the flat coil assembly are both located on the same central axis;

[0038] like Figure 4 As shown, in this embodiment, a through hole is opened in the center of the lower seat plate, and the guide sleeve is aligned with the edge of the through hole; the flat coil assembly is fixed in the guide sleeve, and a notch is opened on one side of the guide sleeve so that the side of the flat coil assembly connected to the external circuit can be placed in the guide sleeve; the sample fixing assembly is fixed to the lower seat plate, and a slide groove is opened, and the two side push clamps are respectively placed in the slide groove, the left shell plate and the right shell plate are respectively opened with threaded holes, and the two side push screws are respectively fixed to the left shell plate and the right shell plate, and the sample support block is placed on the push clamp, and the sample support block is opened with a notch for preventing the sample; a laser speed meter is fixed on the lower seat plate for measuring the speed after the V-shaped hammer head impact is completed; the support column is fixed to the lower seat plate by bolts, and the support column has four pieces respectively located at the four corners of the lower seat plate;

[0039] like Figure 5 As shown, in this embodiment, the flat coil assembly is composed of a flat coil frame and a flat coil, the flat coil frame is made of epoxy resin, and the flat coil is wound by a copper wire along the flat coil frame and embedded in the flat coil frame, so that the outermost turn of the copper wire can fit tightly against the outer wall of the bakelite frame;

[0040] Furthermore, the impact toughness test experimental process is as follows: the prepared sample is placed on the sample support platform, and then the advancing screw and the advancing clamp are adjusted to place the sample on the central axis; the charging switch is closed through the operation panel to connect the charging circuit composed of the rectifier A, the current limiting resistor R and the capacitor group C; the 380V power supply charges the capacitor group C through the charging circuit, and when the charging is completed, the charging switch is disconnected through the operation panel to cut off the charging circuit; and then the high-voltage pulse generator is controlled through the operation panel to generate a high-voltage pulse, triggering the high-frequency thyristor discharge switch to turn on the discharge composed of the capacitor group C and the flat coil assembly. circuit; since the capacitor group C and the coil constitute a typical RLC circuit, the discharge current passing through the flat coil has a decaying oscillation characteristic. According to the law of electromagnetic induction, the current generates an induced current in the high-conductivity drive plate adjacent to it, and the latter generates an induced magnetic field; thus, the coil current magnetic field and the induced current magnetic field are superimposed and enhanced in the gap between the flat coil assembly and the drive disk; this enhanced magnetic field and the induced current of the drive plate cause the drive plate to be subjected to an axially downward pulse load, which is then amplified by the amplifier and acts on the sample through the punch rod and the V-shaped hammer head, realizing the experimental process of the impact toughness test.

[0041] The working process of the impact toughness test device with pulse magnetic field force loading provided in this embodiment is as follows:

[0042] Step 1: Cut the material to be tested for impact toughness into a suitable size and machine a U-shaped notch or a V-shaped notch.

[0043] Step 2: Place the processed specimen in the groove of the specimen support block and adjust the push bolt so that the notch of the specimen is located on the center axis of the impact assembly.

[0044] Step 3: Start the discharge control system to charge the capacitor and store the electrical energy in the capacitor; then, close the discharge switch, and the electrical energy stored in the capacitor will generate a pulse current in the coil through the discharge circuit in a very short time, so that the coil forms a changing magnetic field. According to the law of electromagnetic induction, induced eddy currents are stimulated in the driver plate. The direction of the current in the coil is opposite to the direction of the induced eddy currents in the driver plate. The magnetic fields generated by the two interact with each other to generate a strong electromagnetic force. Under the repulsive effect of the magnetic field, the driver plate moves downward, driving the amplifier, punch, and V-shaped hammer to impact the sample and cause the test to break.

[0045] Step 4: After the discharge is completed, turn off the discharge control system, remove the sample, and calculate the impact absorption energy.

[0046] Step 5: Regarding the calculation of impact absorption work, ignore the change of inductance during the discharge process, establish an equation based on the principle of conservation of energy, and derive the relationship between energy changes in the discharge process.

[0047] Ignore the change of inductance during the discharge process, and establish an equation based on the principle of energy conservation to calculate the discharge process.

[0048] Energy storage dE when the capacitor is discharged z It is mainly used for three parts, namely heat loss dQ during the working process, external work dW, and magnetic field energy dE em , that is:

[0049] dE z =dW+dQ+dE em (1-1)

[0050] Description: E z -Capacitor stores electrical energy; W-mechanical energy; Q-heat loss energy; E em -Magnetic field energy. The electric energy stored in the capacitor is consumed by the coil and the driving copper sheet, so:

[0051] dE z =u1i1dt+u2i2dt (1-2)

[0052] The main circuit excitation voltage and the driving copper sheet eddy current voltage can be expressed as:

[0053]

[0054] The main circuit current and eddy current flux are:

[0055] ψ1=i1L1+i2M 12 (1-5)

[0056] ψ2=i2L2+i1M 12 (1-6)

[0057] Substituting equations (1-3) to (1-6) into equation (1-2), we can obtain:

[0058] dE z =i1 2 R1dt+i2 2 R2dt+i1L1di1+i1M 12 di2+i2L2di2+i2M 12 di1+2i1i2dM 12 (1-7)

[0059] The total magnetic field energy is the sum of the main loop coil magnetic energy, the driving copper sheet induced magnetic energy and the mutual induction magnetic energy of the two:

[0060]

[0061] Because the inductance is a structural parameter, it can be assumed that the inductance of the mechanism remains unchanged during operation, that is, the inductance of the main circuit coil and the equivalent inductance of the driving copper sheet remain unchanged. Differentiating the above formula yields:

[0062] dE em =i1L1di1+i2L2di2+i2M 12 di1+i1M 12 di2+i1i2dM 12 (1-9)

[0063] The heat loss energy is generated by the main circuit coil resistance and the secondary circuit or the equivalent resistance of the driving copper sheet under the action of the main circuit current and the secondary circuit resistance or the current of the driving copper sheet respectively:

[0064] dQ=i1 2 R1dt+i2 2 R2dt (1-10)

[0065] Substituting formulas (1-7), (1-9) and (1-10) into formula (1-1), we can obtain:

[0066] dW=i1i2dM 12 (1-11)

[0067] The mutual inductance between the two circular rings with one turn each is:

[0068]

[0069] Note: μ0-magnetic permeability, μ0=4π×10 -7 H / m; r1- radius of the upper ring; r2- radius of the lower ring; h- vertical distance between the upper and lower rings.

[0070]

[0071] The mutual inductance of the two single-turn coils can be calculated by equation (1-12). The total mutual inductance can be obtained by summing up the mutual inductance between the main loop coil N1 turn and the secondary loop coil N2 turn, which can be expressed as:

[0072]

[0073] Description: M 12ij - the mutual inductance between the i-th turn in coil 1 and the j-th turn in coil 2; N1- the number of turns in the main circuit coil; N2- the equivalent number of turns of the driving copper sheet or the number of turns of coil 2; r 1i -The radius of the i-th turn of the main circuit coil; r 2j - Radius of the jth turn of the driving copper sheet or secondary circuit.

[0074] From (1-12)-(1-16), we can see that M is related to the coil size, the driver plate size, and the distance h between the coil and the driver plate. 12 In this device, the size of the drive plate and the coil are constant, and the distance between the coil and the drive plate changes very little, that is, the change is very small, so it can be obtained:

[0075] W=i1i2M 12 (1-17)

[0076] Energy consumed by spring potential energy:

[0077] E p =1 / 2kΔl 2 (1-18)

[0078] The laser velocimeter is used to measure the speed of the V-shaped hammer after the impact is completed, and then the material kinetic energy formula is used:

[0079] E k =1 / 2mv 2 (1-19)

[0080] The final material impact absorption energy is:

[0081] K=WE p -E k =i1i2M12-1 / 2kΔl 2 -1 / 2mv 2 (1-20)

[0082] The above calculation process can be entered into the computer and you just need to wait for the computer to calculate.

[0083] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. An impact toughness test device loaded with pulse magnetic field force, characterized in that: It includes a combined unit component, an impact component, a flat coil component, a sample fixing component and a control system component; the combined unit component includes a support screw, an upper seat plate, a middle seat plate, a lower seat plate, an upper shell plate, a middle shell protective cover, a right shell plate, a left shell plate, a front shell plate, a rear shell plate, a support column, bolts and nuts; the impact component is arranged between the upper shell plate and the sample fixing component, and the impact component includes a guide sleeve, a drive plate, an insulating lining plate, a punch rod, a punch bolt, a V-shaped hammer head, a reset spring and an amplifier; the flat coil component is arranged between the guide sleeve and the insulating lining plate, and the flat coil component includes a flat coil frame and a flat coil; the sample fixing component is located on the lower seat plate, and the sample fixing component includes a push screw, a push clamp, a test support block and a sample; the control system component includes an operation panel, a telescopic support arm, a laser velocimeter and a discharge system.

2. The impact toughness test device for pulse magnetic field force loading according to claim 1 is characterized in that: The left shell plate, the right shell plate, the upper seat plate and the lower seat plate are integrally formed parts. Slots are formed on the left shell plate and the right shell plate, and the middle seat plate passes through the slots and is placed on the left shell plate and the right shell plate.

3. The impact toughness test device for pulse magnetic field force loading according to claim 1 is characterized in that: The impact assembly includes a guide sleeve fixed to the lower surface of the upper shell plate, the guide sleeve is connected to the upper shell plate through supporting bolts, and the lower surface of the guide sleeve is connected to the lower seat plate; a through hole is opened in the center of the lower seat plate, and the guide sleeve is aligned with the edge of the through hole.

4. The impact toughness test device for pulse magnetic field force loading according to claim 1 is characterized in that: The flat coil assembly is fixed in the guide sleeve, and a notch is provided on one side of the guide sleeve so that the side of the flat coil assembly connected to the external circuit can be placed in the guide sleeve; The middle shell protective sleeve is located below the guide sleeve and above the upper seat plate; the middle shell protective sleeve is provided with a through hole for connecting the flat coil assembly wire to an external circuit.

5. The impact toughness test device for pulse magnetic field force loading according to claim 1, characterized in that: The impact assembly includes the guide sleeve, and a driving plate and an insulating lining plate that can move up and down along the inner wall of the guide sleeve are installed below the flat coil assembly. An amplifier is fixedly connected to the lower surface of the insulating lining plate, and a punch bar is fixedly connected to the lower end of the amplifier. A V-shaped hammer head is fixedly connected to the punch bar through a punch bolt, and the impact assembly and the flat coil assembly are both located on the same central axis; The driving plate is made of red copper, and the amplifier is a conical column shape that is larger at the top and smaller at the bottom, with the side close to the driving plate being larger and the part connected to the punch rod being smaller.

6. The impact toughness test device for pulse magnetic field force loading according to claim 1, characterized in that: The flat coil assembly is composed of a flat coil frame and a flat coil, the flat coil frame is made of epoxy resin, the flat coil is wound by a copper wire along the flat coil frame and embedded in the flat coil frame, so that the outermost turn of the copper wire can fit closely to the outer wall of the bakelite frame; The copper conductor is made of a copper strip, and an insulating tape with high compressive strength is wrapped around the copper strip to achieve electrical insulation between the turns. The flat coil assembly converts electrical energy into the impact force of the impact assembly, and the flat coil circuit is connected to an external circuit. An insulating lining is placed on the flat coil assembly, and the insulating lining material is an insulating material such as rubber.

7. The impact toughness test device loaded by pulse magnetic field force according to claim 1, characterized in that: The lower seat plate is fixed with the sample fixing assembly and has a slide groove, the two side push clamps are respectively placed in the slide groove, the left shell plate and the right shell plate are respectively provided with threaded holes, the two side push screws are respectively fixed to the left shell plate and the right shell plate, the sample support block is placed on the push clamp, and the sample support block has a notch for preventing the sample; A laser speed meter is fixed on the lower seat plate to measure the speed of the V-shaped hammer after the impact is completed.

8. The impact toughness test device for pulse magnetic field force loading according to claim 1, characterized in that: The guide sleeve and the amplifier are located above the upper seat plate. A through hole is provided in the center of the middle seat plate. The oil-free lubricating sleeve is placed in the through hole in the center of the middle seat plate. The punch rod passes through the oil-free lubricating sleeve and the middle seat plate. The reset spring is located above the oil-free lubricating sleeve and coincides with its axis. The punch rod passes through the reset spring. The reset spring can reset the impact assembly after each discharge on the one hand, and on the other hand, it plays a buffering role between the middle die seat plate and the impact unit to prevent the amplifier from colliding with the middle die seat plate.

9. The impact toughness test device loaded with pulse magnetic field force according to claim 1, characterized in that: The support column is fixed to the lower seat plate by bolts, and there are four support columns respectively located at the four corners of the lower seat plate; The telescopic support arm is fixedly connected to the upper seat plate, the operation panel is fixedly connected to the end of the telescopic support arm, and the discharge system and the laser tester are respectively connected to the operation panel for control.

10. A pulse magnetic field force loading impact toughness test method, characterized in that: An impact toughness test device loaded with a pulse magnetic field force as described in any one of claims 1 to 9 above is used: the prepared sample is placed on the sample support platform, and then the push screw and the push clamp are adjusted to place the sample on the central axis; the charging switch is closed through the operation panel to connect the charging circuit composed of the rectifier A, the current limiting resistor R and the capacitor group C; the 380V power supply charges the capacitor group C through the charging circuit, and when the charging is completed, the charging switch is disconnected through the operation panel to cut off the charging circuit; then the high-voltage pulse generator is controlled through the operation panel to generate a high-voltage pulse, triggering the high-frequency thyristor discharge switch to turn on the capacitor group C, the flat The plate coil assembly forms a discharge circuit; since the capacitor group C and the coil form a typical RLC circuit, the discharge current passing through the flat coil has a decaying oscillation characteristic. According to the law of electromagnetic induction, this current generates an induced current in the high-conductivity drive plate adjacent to it, and the latter generates an induced magnetic field; thus, the coil current magnetic field and the induced current magnetic field are superimposed and enhanced in the gap between the flat coil assembly and the drive disk; this enhanced magnetic field and the induced current of the drive plate cause the drive plate to be subjected to an axially downward pulse load, which is then amplified by the amplifier and acts on the sample through the punch rod and the V-shaped hammer head, realizing the experimental process of the impact toughness test.

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