Magnetic suspension density measurement method and device based on magnetic Archimedes principle

Abstract

The invention discloses a density measurement method and device based on the magnetic Archimedes principle, a magnetic suspension measurement device comprises a base, the base is symmetrically provided with two magnet installation cavities used for installing magnets, and the two magnet installation cavities are internally provided with a first magnet and a second magnet respectively; a transparent container is placed between the two magnet mounting seats, a spring is mounted on the side wall, close to the bottom, of the transparent container, an adjustable inclined plate assembly used for placing a to-be-tested sample is arranged in the transparent container, the adjustable inclined plate assembly is connected with the spring, and the adjustable inclined plate assembly inclines upwards. The magnetic suspension measuring device is simple in structure, low in cost, capable of being used for measuring some high-precision fine metal workpieces, capable of efficiently utilizing raw materials, free of requirements for the size and the shape of needed materials and easy and convenient to operate, the measuring range of a magnetic suspension measuring method can be expanded through the design of a transverse structure and the adjustable inclined plate, and the machining efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to density measurement methods, specifically to a density measurement method and apparatus based on the magnetic Archimedes principle. Background Technology

[0002] Density measurement has a wide range of applications. It is not only a fundamental concept in physics, but also plays a crucial role in scientific research, industrial production, and daily life. It serves scientific research, ensures the quality of industrial products, optimizes material selection, is used for product identification and quality assessment, and is closely related to daily life.

[0003] Density measurement is the scientific method of determining the mass per unit volume of a substance. ,in For density, For quality, Density measurement is a technical process that involves accurately obtaining the mass and volume of a sample, and then calculating the density value using the density formula. As an inherent property of matter, density measurement is not only a fundamental means of material characterization but also a key technology for distinguishing substances, analyzing components, assessing purity, and optimizing processes. It is widely used in scientific research, industry, and biomedicine, playing an irreplaceable role, especially in submicron particle separation and characterization, and the analysis of magnetically levitated materials. Traditional density measurement methods include the specific gravity bottle method and the density gradient tube method. The specific gravity bottle method uses a fixed-volume container (specific gravity bottle) combined with a liquid displacement method to calculate the sample volume by accurately weighing the mass difference, and finally calculates the density value using the density formula. Deriving sample density. The density gradient tube method utilizes two miscible liquids to prepare a system with a continuous density gradient. The sample is suspended in the corresponding density layer in the tube, and the sample density is calculated through gradient calibration.

[0004] The methods described above are widely used and relatively mature in practical measurements. However, they still have some drawbacks. With the continuous development of technology, traditional density measurement techniques are gradually revealing their limitations. The specific gravity bottle method is cumbersome to operate, easily affected by sample adsorption and residual filling solution, and is not suitable for volatile or porous samples; the density gradient tube method has poor gradient stability, is easily affected by temperature, and has a limited measurement range (usually 0.8-1.5 g / cm³). 3 Existing magnetic levitation density measurement methods based on the magneto-Archimedes principle can disregard sample size and shape, but are limited by their measurement range (typically 0.8–2.3 g / cm³). 3 Traditional density measurement techniques typically have requirements regarding the size and shape of raw materials, and suffer from drawbacks such as complex operation and poor stability, which not only increases costs but also leads to waste.

[0005] Therefore, this invention proposes a method and device for measuring magnetic levitation density based on the magnetic Archimedes principle. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a magnetic levitation density measurement method and device based on the magnetic Archimedes principle. The device is simple to operate, reasonably designed, and accurately measures the density.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: A magnetic levitation measuring device includes a base with two symmetrically arranged magnet mounting chambers for mounting magnets. A magnet 1 and a magnet 2 are respectively installed in the two magnet mounting chambers. A transparent container is placed between the two magnet mounting chambers. A spring is installed on the side wall of the transparent container near the bottom. An adjustable inclined plate assembly for placing the sample to be tested is provided inside the transparent container. The adjustable inclined plate assembly is connected to the spring and is tilted upwards.

[0008] Furthermore, the adjustable ramp assembly includes a horizontal plate and a vertical rod perpendicular to the horizontal plate, wherein the sample to be tested is placed on the horizontal plate, and the horizontal plate is connected to a spring.

[0009] Furthermore, the base has a groove for accommodating a transparent container, which is placed in the groove, with several pads placed at the bottom of the transparent container.

[0010] Furthermore, the groove is located between two magnet mounting chambers. A pair of elongated slots are symmetrically opened on the upper and lower surfaces of the magnet mounting chambers. When the magnet is installed in the corresponding magnet mounting chamber, it is inserted into the two elongated slots through the plug plate of the baffle to limit the position of the magnet.

[0011] Furthermore, the first magnet and the second magnet are opposite each other with the same poles, and the distance between the first magnet and the second magnet is less than or equal to 70 mm. The transparent container is filled with a medium solution, wherein the medium solution is a paramagnetic aqueous solution.

[0012] This invention also proposes a density measurement method based on the magnetic-Archimedes principle, comprising the following steps: 1) First, estimate the density and volume of the sample to be tested based on the material of the sample, prepare the corresponding medium solution and add it into a transparent container; 2) Then, rinse the sample with ethanol and set aside. 3) After step 2) is completed, place the sample to be tested obtained in step 2) into the transparent container in step 1); 4) After step 3) is completed, place the transparent container from step 3) into the groove of the magnetic levitation measuring device, that is, between magnet one and magnet two, and add shims to adjust the height of the transparent container so that the sample to be tested is at the center line of the magnet. 5) After step 4) is completed, observe the suspension state of the sample and take a picture with a camera. Adjust the adjustable inclined plate assembly by adjusting the angle between the adjustable inclined plate assembly and the transparent container. The sample to be tested is suspended. After suspension is completed and the sample is left to stand for a period of time, it can be seen that the sample is stably suspended in this position. 6) After step 5) is completed, use image processing software to measure the distance between the sample and magnet 1. and the angle between the adjustable ramp assembly and the transparent container. ; 7) After step 6) is completed, measure the distance between the sample to be tested and magnet one. and the angle between the adjustable ramp assembly and the transparent container. Substitute the values ​​into the formula to complete the density calculation.

[0013] Furthermore, the medium solution in step 1) is an aqueous solution of MnCl2.

[0014] Furthermore, the formula in step 7) is:

[0015]

[0016]

[0017] In the formula: For the density of the object, It represents lateral suspension displacement.

[0018] Furthermore, when the distance between magnet one and magnet two... A high-density sample with a diameter of 45 mm in a paramagnetic solution is subjected to the combined effects of gravity, buoyancy, the support force from the inclined plane, and the magnetic field. When these four forces are in equilibrium, the sample reaches a stable suspension state. The force formulas at equilibrium are shown below:

[0019]

[0020]

[0021]

[0022] In the formula: is the magnetic susceptibility. For density, subscript and These represent the sample and the medium solution, respectively. The volume of the sample being tested; It represents the magnetic flux density; For vector gradient operators; It is the acceleration due to gravity; Permeability of free space; When the sample to be tested is along When displacement occurs in the axial direction, it is in The displacement fluctuation in the axial direction is less than ±3 mm, and this magnitude of displacement will not have a significant impact on the overall force analysis results. The process of force equilibrium occurs in In a plane, therefore the magnetic field is Components of the axis The value is 0, and the magnetic field gradient force is zero. exist The component along the axial direction is also 0; at the same time, exist The axial component is 10. -5 T 2 / m, much smaller than its in The axial component; furthermore, near the system centerline, Directional magnetic field components 10 -3 T, compared to Directional magnetic field components Two orders of magnitude lower; based on the above analysis, equation (IV) can be further simplified to:

[0023] When the two magnets used are N52 neodymium iron boron magnets with dimensions of 50mm × 50mm × 25mm, exist The change on the axis is linear, from the left side of the magnet's surface. =0 (maximum value) + B0 becomes the right side of the magnet's two surfaces. =minimum value of d - B0; magnetic field strength along the centerline of the magnetic levitation device for

[0024] Using the force equilibrium formula (I), centerline With lateral displacement By applying the parallelogram law and combining equations (II), (III), (V), and (VI), we can obtain the following relationship:

[0025] In the formula: For the density of the object, It represents lateral suspension displacement.

[0026] Further, solve equation (7) to obtain the formula in step 7).

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) The device of the present invention is reasonably designed, simple to operate, and low in cost. It can be used to measure some high-precision small metal workpieces and can make efficient use of raw materials. It does not require the size and shape of the required materials. It is easy to operate. Furthermore, the design of the transverse structure and adjustable inclined plate expands the range of the magnetic levitation measurement method and greatly improves the processing efficiency. 2) The magnetic levitation density measurement method of the present invention has high measurement accuracy and a large measurement range, and is suitable for measuring high-density samples. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the magnetic levitation device of the present invention; Figure 2 A structural diagram showing the base and magnet mounting chamber of this invention; Figure 3 This is a schematic diagram of the baffle structure of the present invention; Figure 4 For the present invention, the length is 50mm × 50mm wide With a magnetic field strength of 0.395T at the center surface of a 25mm high magnet, and a distance of 45mm from the center line, the magnetic field strength is... With lateral displacement A graph illustrating the relationship; Figure 5 This illustrates the force conditions on the sample during the magnetic levitation density measurement process of this invention. Figure 6 This is a schematic diagram illustrating the measurement process of method 1 in an embodiment of the present invention; Figure 7 The following are the density-displacement curves and measurement results of Method 1 in this embodiment of the invention; Figure 8 This is a schematic diagram illustrating the measurement process of method 2 in embodiment 2 of the present invention; Figure 9 The density-angle curve and measurement results of method 2 in embodiment 2 of the present invention are shown below; Figure 10 This is a schematic diagram illustrating the measurement process of method 3 in embodiment 3 of the present invention; Figure 11 The diagram shows the density-displacement-angle curve and measurement results of method 3 in embodiment 3 of the present invention.

[0029] In the diagram: 1. Base; 2. Magnet mounting chamber; 201. Long groove; 3. Magnet one; 4. Magnet two; 5. Transparent container; 6. Spring; 7. Sample to be tested; 8. Adjustable inclined plate assembly; 801. Horizontal plate; 802. Vertical rod; 9. Gasket; 10. Baffle; 1011. Connecting plate; 11. Paramagnetic solution. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to the scope described.

[0031] Please refer to Figure 1-3 A magnetic levitation measuring device includes a base 1, on which two magnet mounting chambers 2 are symmetrically arranged for mounting magnets. Magnet 1 3 and magnet 2 4 are respectively installed inside the two magnet mounting chambers 2. A transparent container 5 is placed between the two magnet mounting chambers 2. A spring 6 is installed on the side wall of the transparent container 5 near the bottom. An adjustable inclined plate assembly 8 for placing a sample 7 to be tested is provided inside the transparent container 5. The adjustable inclined plate assembly 8 is connected to the spring 6 and is tilted upward.

[0032] The adjustable ramp assembly 8 includes a horizontal plate 801 and a vertical rod 802 perpendicular to the horizontal plate 801, wherein the sample to be tested 7 is placed on the horizontal plate 801, and the horizontal plate 801 is connected to the spring 6.

[0033] The base 1 has a groove for accommodating the transparent container 5. The transparent container 5 is placed in the groove, and several pads 9 are placed at the bottom of the transparent container 5.

[0034] The groove is located between two magnet mounting chambers 2. A pair of elongated slots 201 are symmetrically opened on the upper and lower surfaces of the magnet mounting chambers 2. When the magnet is installed in the corresponding magnet mounting chamber 2, it is inserted into the two elongated slots 201 through the plug plate 1011 of the baffle 10 to limit the position of the magnet.

[0035] Magnet 3 and magnet 4 are opposite each other with the same poles, and the distance between magnet 3 and magnet 4 is less than or equal to 70 mm. The transparent container 5 contains a medium solution, which is a paramagnetic aqueous solution.

[0036] In this embodiment, both magnet 3 and magnet 4 are 50mm long × 50mm wide A square magnet with a height of 25mm, a central surface magnetic induction intensity of 0.395T, and two magnets with the same poles facing each other at a distance of 45mm.

[0037] This invention also proposes a density measurement method based on the magnetic-Archimedes principle, comprising the following steps: 1) First, based on the material of the sample to be tested 7, estimate the density and volume of the sample in advance, prepare the corresponding medium solution and add it into the transparent container 5; 2) Then, rinse the sample 7 with ethanol and set aside. 3) After step 2) is completed, place the sample 7 obtained in step 2) into the transparent container 5 in step 1); 4) After step 3) is completed, place the transparent container from step 3) into the groove in the magnetic levitation measuring device, that is, between magnet 3 and magnet 4, and add shims 9 to adjust the height of the transparent container 5 so that the sample 7 to be tested is at the center line of the magnet. 5) After step 4) is completed, observe the suspension state of the sample 7 and take a picture with a camera. Adjust the adjustable inclined plate assembly 8 by adjusting the angle between the adjustable inclined plate assembly 8 and the transparent container 5. Suspend the sample 7 to be tested. After suspension is completed and the sample is left to stand for a period of time, it can be seen that the sample is stably suspended in this position. 6) After step 5) is completed, use image processing software to measure the distance between the sample 7 and the magnet 3 using the image obtained in step 5). and the angle between the adjustable ramp assembly 8 and the transparent container 5. ; 7) After step 6) is completed, adjust the distance between the sample to be tested 7 and the magnet 3. and the angle between the adjustable ramp assembly 8 and the transparent container 5. Substitute the values ​​into the formula to complete the density calculation.

[0038] Furthermore, the medium solution in step 1) is an aqueous solution of MnCl2.

[0039] Furthermore, the formula in step 7) is:

[0040]

[0041]

[0042] In the formula: For the density of the object, It represents lateral suspension displacement.

[0043] The magnetic levitation density measurement method based on the magnetic Archimedes principle is as follows: In the magnetic levitation density measurement device for high-density samples, two neodymium iron boron magnets, one on the left and one on the right, are placed horizontally with their N poles facing each other, with a distance between them. Adjust the slope angle This allows the sample to be stably suspended on an inclined plane in a paramagnetic solution, generating a lateral suspension displacement. The density of the sample is calculated based on its lateral suspension displacement and the angle of the inclined plane. In this device... A 45mm high-density sample in a paramagnetic solution is subjected to the combined effects of gravity, buoyancy, the supporting force of the inclined plane, and the magnetic field. Figure 4 It can be seen that when the four forces are in equilibrium, the sample reaches a stable suspension state. The force formulas at equilibrium are shown below:

[0044]

[0045]

[0046]

[0047] In the formula: , is the magnetic susceptibility For density, subscript and These represent the sample and the medium solution, respectively. The volume of the sample being tested; It represents the magnetic flux density; For vector gradient operators; It is the acceleration due to gravity; is the vacuum permeability.

[0048] In the same paramagnetic medium system, gravity and buoyancy remain constant. Establish a three-dimensional Cartesian coordinate system, and let... The axis is parallel to the direction of gravity; thanks to the symmetry of the magnets, the system... shaft and The shafts are equivalent, that is plane and The magnetic field distribution in the plane is completely uniform. In the experiment presented in this paper, when the sample along... When displacement occurs in the axial direction, it is in The displacement fluctuation in the axial direction is less than ±3 mm, and this magnitude of displacement will not have a significant impact on the overall stress analysis results.

[0049] The process of force equilibrium occurs in In a plane, therefore the magnetic field is Components of the axis It must be 0, and the magnetic field gradient force exist The component along the axial direction is also 0. Meanwhile, exist The axial component is approximately 10. -5 T² / m, much smaller than its T² / m, is Components in the axial direction (approximately 10) -3T² / m); In addition, near the system centerline, Directional magnetic field components Approximately 10 -3 T, compared to Directional magnetic field components (approximately 10) -1 T) is two orders of magnitude lower. Based on the above analysis, equation (IV) can be further simplified.

[0050]

[0051] According to the magnet used (N52 neodymium iron boron magnet, size 50mm×50mm×25mm). exist The change along the axis (from the surface of the left magnet to the surface of the right magnet) is almost linear. =0.999). From the left side of the magnet surface ( =0) maximum value + B 0 becomes the surface of the magnet on the right ( = d Minimum value of ) B 0. Magnetic field strength along the centerline of the magnetic levitation device. for

[0052] Using the force balance formula (I) and Figure 4 By applying the parallelogram law and combining equations (II), (III), (V), and (VI), we can obtain...

[0053] In the formula: For the density of the object, For the lateral suspension displacement, solving equation (VII) yields the following:

[0054]

[0055]

[0056] As can be seen from equation (VIII), when the paramagnetic solution, the magnet, and the angle of the inclined plate are given, and They are directly proportional.

[0057] Solve equation (VII) to obtain the formula in step 7). Example 1

[0058] This method was used to measure the density of copper spheres, tin spheres, zirconia ceramic spheres, aluminum spheres, and glass spheres (spherical particles with a diameter of approximately 3-5 mm). Their standard densities were 8.900, 7.360, 5.600, 2.700, and 2.400 g / cm³, respectively. 3 After cleaning the sample surface with alcohol, it is placed in an aqueous MnCl2 solution, then placed in the apparatus. The angle of the inclined plate is adjusted, and the sample is allowed to stand for 2 minutes until its suspension position stabilizes. The distance from the sample to the left magnet and the angle of the inclined plate are measured, and the data are recorded. The density of the sample can be calculated by substituting the data into the formula.

[0059] The three different measurement methods are explained in detail.

[0060] Method 1 presents the suspension of high-density samples at different positions within a transverse magnetic levitation device at the same angle. Three sets of comparisons are conducted using different angles. Figure 6-7 It can be seen that, When the angle of the inclined plane is uniformly 1.70°, the copper ball, tin ball, and zirconia ceramic ball successfully levitate, while the aluminum ball and glass ball fail to levitate. According to equation (VIII), the densities of the copper ball, tin ball, and zirconia ceramic ball are calculated to be 8.887, 7.367, and 5.592 g / cm³, respectively. 3 The errors between the measured results and the theoretical density were -0.013, 0.007, and -0.008 g / cm³, respectively. 3 .

[0061] When the angle of the inclined plane was uniformly 3.00°, only the zirconia ceramic spheres successfully levitated. According to equation (VIII), the density of the zirconia ceramic spheres was calculated to be 5.606 g / cm³. 3 The measurement result differs from the theoretical density by 0.006 g / cm³. 3 .

[0062] When the angle of the inclined plane is uniformly 5.00°, the aluminum and glass spheres successfully levitate, while the copper, tin, and zirconia ceramic spheres fail to levitate. According to equation (VIII), the densities of the aluminum and glass spheres are calculated to be 2.694 and 2.394 g / cm³, respectively. 3 The error between the measured result and the theoretical density is -0.006 g / cm³. 3 .

[0063] A linear density-displacement curve is obtained at different positions at the same angle. Based on the sample's suspension position, the distance between the sample and the center of the left magnet surface is determined, and the sample's density can then be calculated.

[0064] Method 2 presents the suspension of high-density samples at different angles at the same position within a transverse magnetic levitation device. Figure 8-9 It can be known that: When the distance from all samples to the left magnet is 6.25 mm, all samples can be suspended. According to equation (8), the densities of the copper ball, tin ball, zirconia ceramic ball, aluminum ball, and glass ball are calculated to be 8.887, 7.439, 5.593, 2.699, and 2.399 g / cm³, respectively. 3 The errors between the measured results and the theoretical density were -0.013, 0.079, -0.007, -0.001, and -0.001 g / cm³, respectively. 3 .

[0065] When all samples are 9.50 mm away from the left-side magnet, the copper ball cannot levitate. According to equation (VIII), the densities of the tin ball, zirconia ceramic ball, aluminum ball, and glass ball are calculated to be 7.368, 5.594, 2.699, and 2.405 g / cm³, respectively. 3 The errors between the measured results and the theoretical density were 0.008, -0.006, -0.001, and 0.005 g / cm³, respectively. 3 .

[0066] When all samples are 13.30 mm away from the left-hand magnet, the copper and tin balls cannot levitate. According to equation (VIII), the densities of the zirconia ceramic ball, aluminum ball, and glass ball are calculated to be 5.591, 2.694, and 2.395 g / cm³, respectively. 3 The errors between the measured results and the theoretical density were -0.009, -0.006, and -0.005 g / cm³, respectively. 3 .

[0067] Nonlinear density-angle curves were obtained for the same location at different angles. The density curves show that this method can achieve higher accuracy when measuring samples with lower densities.

[0068] In Method 3, the high-density sample is suspended in the device. Three sets of cases were set up for comparison, so that the sample is in a random suspension state at different angles and positions. Figure 10-11 It can be known that: The distances between the copper ball, tin ball, zirconia ceramic ball, aluminum ball, and glass ball and the center of the left-side magnet surface are 5.31, 7.39, 8.52, 14.43, and 15.30 mm, respectively, corresponding to inclined plate angles of 1.80°, 2.00°, 2.60°, 4.50°, and 5.20°. Substituting these values ​​into the formula yields the sample density. According to formula (VIII), the calculated densities for each sample are 8.879, 7.294, 5.562, 2.714, and 2.389 g / cm³, respectively. 3 The errors between the measured results and the theoretical density were -0.021, -0.066, -0.038, 0.014, and -0.011 g / cm³, respectively.3 It presents the suspension status of high-density samples at any position in a transverse magnetic levitation device, and can obtain density-displacement-angle surface plots at any position. This allows for more comprehensive and convenient acquisition of density data for various samples under corresponding suspension states.

Claims

1. A magnetic levitation measuring device, characterized in that... Includes a base (1), on which two magnet mounting chambers (2) for mounting magnets are symmetrically arranged. Magnet one (3) and magnet two (4) are respectively installed inside the two magnet mounting chambers (2). A transparent container (5) is placed between the two magnet mounting chambers (2). A spring (6) is installed on the side wall of the transparent container (5) near the bottom. An adjustable inclined plate assembly (8) for placing the sample to be tested (7) is provided inside the transparent container (5). The adjustable inclined plate assembly (8) is connected to the spring (6) and the adjustable inclined plate assembly (8) is tilted upward.

2. The magnetic levitation measuring device according to claim 1, characterized in that... The adjustable ramp assembly (8) includes a horizontal plate (801) and a vertical rod (802) perpendicular to the horizontal plate (801), wherein the sample to be tested (7) is placed on the horizontal plate (801), and the horizontal plate (801) is connected to a spring (6).

3. The magnetic levitation measuring device according to claim 1, characterized in that... The base (1) has a groove for accommodating a transparent container (5), which is placed in the groove, and the bottom of the transparent container (5) is padded with several pads (9).

4. A magnetic levitation measuring device according to claim 3, characterized in that... The groove is located between two magnet mounting chambers (2). A pair of elongated slots (201) are symmetrically opened on the upper and lower surfaces of the magnet mounting chambers (2). When the magnet is installed in the corresponding magnet mounting chamber (2), it is inserted into the two elongated slots (201) through the plug plate (1011) of the baffle (10) to limit the position of the magnet.

5. A magnetic levitation measuring device according to claim 4, characterized in that... The magnets 1 (3) and 2 (4) are opposite each other with the same poles, and the distance between the magnets 1 (3) and 2 (4) is less than or equal to 70 mm. The transparent container (5) contains a medium solution, wherein the medium solution is a paramagnetic aqueous solution.

6. A density measurement method based on the magnetic Archimedes principle, characterized in that... Includes the following steps: 1) First, based on the material of the sample to be tested (7), estimate the density and volume of the sample to be tested in advance, prepare the corresponding medium solution and add it into the transparent container (5); 2) Then, rinse the sample (7) with ethanol and set aside; 3) After step 2) is completed, place the sample (7) to be tested obtained in step 2) into the transparent container (5) in step 1); 4) After step 3) is completed, place the transparent container of step 3) into the groove of the magnetic levitation measuring device as described in any one of claims 1-5, that is, between magnet one (3) and magnet two (4), and add a shim (9) to adjust the height of the transparent container (5) so that the sample to be tested (7) is at the center line position of the magnet. 5) After step 4) is completed, observe the suspension state of the sample (7) and take a picture with a camera. Adjust the adjustable inclined plate assembly (8) and adjust the angle between the adjustable inclined plate assembly (8) and the transparent container (5). The sample to be tested (7) is suspended. After the suspension is completed and the sample is left to stand for a period of time, it can be seen that the sample is stably suspended in this position. 6) After step 5) is completed, use image processing software to measure the distance between the sample (7) and magnet (3) obtained in step 5). and the angle between the adjustable ramp assembly (8) and the transparent container (5). ; 7) After step 6) is completed, the distance between the sample to be tested (7) and magnet 1 (3) is measured. and the angle between the adjustable ramp assembly (8) and the transparent container (5). Substitute the values ​​into the formula to complete the density calculation.

7. The density measurement method based on the magnetic Archimedes principle according to claim 6, characterized in that... The medium solution in step 1) is an aqueous solution of MnCl2.

8. A density measurement method based on the magnetic Archimedes principle according to claim 7, characterized in that... The formula in step 7) is: In the formula: For the density of the object, This is a lateral suspension displacement.

9. A density measurement method based on the magnetic Archimedes principle according to claim 8, characterized in that... When the distance between magnet one (3) and magnet two (4) A high-density sample with a diameter of 45 mm in a paramagnetic solution is subjected to the combined effects of gravity, buoyancy, the support force from the inclined plane, and the magnetic field. When these four forces are in equilibrium, the sample reaches a stable suspension state. The force formulas at equilibrium are shown below: In the formula: , is the magnetic susceptibility For density, subscript and These represent the sample and the medium solution, respectively. The volume of the sample being tested; It represents the magnetic flux density; For vector gradient operators; It is the acceleration due to gravity; The vacuum permeability; When the sample to be tested (7) is along When displacement occurs in the axial direction, it is in The displacement fluctuation in the axial direction is less than ±3 mm, and this magnitude of displacement will not have a significant impact on the overall force analysis results. The process of force equilibrium occurs in In a plane, therefore the magnetic field is Components of the axis The value is 0, and the magnetic field gradient force is zero. exist The component along the axial direction is also 0; at the same time, exist The axial component is 10. -5 T 2 / m, much smaller than its in The axial component; furthermore, near the system centerline, Directional magnetic field components 10 -3 T, compared to Directional magnetic field components Two orders of magnitude lower; based on the above analysis, equation (IV) can be further simplified to: When the two magnets used are N52 neodymium iron boron magnets with dimensions of 50mm × 50mm × 25mm, exist The change on the axis is linear, from the left side of the magnet surface (3). =0 maximum value +B0 becomes the right side magnet two (4) surface =minimum value of d - B0; magnetic field strength along the centerline of the magnetic levitation device for Using the force equilibrium formula (I), centerline With lateral displacement By applying the parallelogram law and combining equations (II), (III), (V), and (VI), we can obtain the following relationship: In the formula: For the density of the object, This is a lateral suspension displacement.

10. A density measurement method based on the magnetic Archimedes principle according to claim 9, characterized in that... Solve equation (VII) to obtain the formula in step 7).

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