Magnetizing method for high-stability permanent magnet with specified magnetic induction intensity

Abstract

The invention discloses a magnetizing method for a high-stability permanent magnet with specified magnetic induction intensity, which belongs to the technical field of permanent magnet magnetizing, and comprises the following steps of: firstly, carrying out saturated magnetizing: controlling an external magnetic field based on the magnetic field intensity required by the saturation of the permanent magnet, and magnetizing the permanent magnet to be saturated; and quantitative demagnetization: adopting an alternating magnetic field to quantitatively demagnetize the permanent magnet, and detecting the magnetic induction intensity of the permanent magnet at the same time. If the magnetic induction intensity of the demagnetized permanent magnet meets the requirement, the process is ended; if the magnetic induction intensity of the demagnetized permanent magnet is smaller than the demand, saturation magnetization and quantitative demagnetization are carried out again, and the control voltage of the alternating magnetic field is reduced; if the magnetic induction intensity of the permanent magnet demagnetized for the first time is larger than the requirement, quantitative demagnetization is continuously conducted till the requirement is met. According to the invention, high-stability magnetizing with specified magnetic induction intensity is realized, and the practicability is relatively good.

Description

Technical Field

[0001] This invention belongs to the technical field of permanent magnet magnetization, specifically relating to a method for magnetizing a high-stability permanent magnet to a specified magnetic induction intensity. Background Technology

[0002] Permanent magnets have wide applications in modern industry, electronic equipment, and scientific research. Their performance directly determines the function and efficiency of related devices. However, practical applications of permanent magnets often require precise control of their remanence (i.e., the magnetic field strength retained after magnetization) to meet the needs of different application scenarios. Quantitative magnetization technology is a key technology developed to achieve this goal. In actual production, permanent magnet materials are usually heat-treated or machined and then magnetized using an external magnetic field to achieve a predetermined remanence state. However, different applications have significantly different requirements for the remanence of permanent magnets. For example, high-performance motors require high remanence density to improve efficiency, while some sensors require lower remanence to avoid interference. Therefore, how to precisely control the magnetic field strength of permanent magnets has become a significant technical challenge. Traditional quantitative magnetization methods typically apply a preset magnetic field strength to the permanent magnet, but quantitative control is difficult to achieve, easily leading to oversaturation or undersaturation of the material, thus affecting the performance of permanent magnet devices. Summary of the Invention

[0003] The purpose of this invention is to provide a magnetization method for a specified magnetic induction intensity of a highly stable permanent magnet, thereby solving the aforementioned problems.

[0004] This invention is mainly achieved through the following technical solutions: A magnetization method for a specified magnetic flux density of a high-stability permanent magnet includes the following steps: Step S1: Saturation magnetization: Based on the magnetic field strength required for permanent magnet saturation, control the external magnetic field to magnetize the permanent magnet to saturation; Step S2: Quantitative demagnetization: The permanent magnet is demagnetized quantitatively using an alternating magnetic field, while the magnetic induction intensity of the permanent magnet is detected. Step S3: If the magnetic induction intensity of the demagnetized permanent magnet meets the requirements, the process ends; Step S4: If the magnetic induction intensity of the demagnetized permanent magnet is less than the requirement, proceed to step S1 and reduce the control voltage of the alternating magnetic field in step S2; thereby reducing the peak magnetic field intensity H0 of the demagnetizing alternating magnetic field and reducing the amount of demagnetization in one operation. Step S5: If the magnetic induction intensity of the demagnetized permanent magnet is greater than the requirement, proceed to step S2.

[0005] In this invention, an alternating magnetic field is generated using an energized coreless coil. The estimation formula for the relationship between the coil magnetic field H and the control voltage V is as follows: ; Where: N is the number of turns of the coreless coil; Z is the impedance of the coreless coil; This represents the length of the magnetic circuit.

[0006] To better realize the present invention, in step S1, the external magnetic field is continuously increased until the magnetic induction intensity of the permanent magnet no longer increases. At this time, the external magnetic field intensity is the magnetic field intensity required for the permanent magnet to saturate.

[0007] To better realize the present invention, in step S1, an external magnetic field with a magnetic field strength exceeding that required for permanent magnet saturation is used to magnetize the permanent magnet to saturation.

[0008] To better realize the present invention, further, in step S5, proceed to step S2 and increase the control voltage of the alternating magnetic field in step S2.

[0009] To better realize the present invention, further, in step S5, proceed to step S1 and reduce the control voltage of the alternating magnetic field in step S2.

[0010] To better realize the present invention, further, in steps S3 to S5, the magnetic induction intensity of the permanent magnet after the first demagnetization is determined to be equal to the set requirement.

[0011] The beneficial effects of this invention are as follows: This invention employs a method of first saturating the magnet with magnetization followed by quantitative demagnetization to achieve a specified magnetic flux density. After quantitative demagnetization, the magnetic flux density of the permanent magnet is measured, and the demagnetization control voltage is increased or decreased based on the measurement result. If the magnetic flux density is too high, the demagnetization control voltage is increased, and demagnetization is repeated; if the magnetic flux density is too low, magnetization is repeated until saturation, while the subsequent demagnetization control voltage is decreased, thus achieving magnetization control at the specified magnetic flux density. This invention achieves highly stable magnetization at a specified magnetic flux density and has good practicality. Attached Figure Description

[0012] Figure 1 A flowchart of a magnetization method for specifying the magnetic induction intensity of the high-stability permanent magnet of the present invention. Detailed Implementation

[0013] Example 1: A magnetization method for a specified magnetic flux density of a high-stability permanent magnet employs a process of first saturating the magnet and then quantitatively demagnetizing it. Specifically, the permanent magnet is first saturated with an external magnetic field exceeding the required saturation strength. Then, a voltage-controlled alternating magnetic field is used to quantitatively demagnetize the permanent magnet. After the initial demagnetization, the magnetic flux density of the permanent magnet is measured. If the requirement is met, the process ends; otherwise, demagnetization is repeated based on the measurement results, either by re-saturating and re-magnetizing before demagnetization, until the measurement results meet the requirements.

[0014] Preferably, such as Figure 1 As shown, the present invention specifically includes the following steps: (1) Continuously increase the external magnetic field to magnetize until the magnetic induction intensity of the permanent magnet no longer increases. At this point, the external magnetic field intensity is determined to be the magnetic field intensity required for the permanent magnet to saturate. (2) Magnetize the permanent magnet to saturation using a magnetic field strength slightly exceeding that required for permanent magnet saturation; (3) Detect the current magnetic induction intensity of the permanent magnet; based on the detection results, use voltage to control a certain amount of alternating magnetic field to demagnetize the permanent magnet quantitatively; (4) Detect the magnetic induction intensity of the permanent magnet after the first demagnetization. If the magnetic induction intensity of the permanent magnet after the first demagnetization meets the requirements, the process ends. If the magnetic induction intensity of the permanent magnet after the first demagnetization is less than the set requirements, proceed to step (2) above and reduce the subsequent demagnetization control voltage. If the magnetic induction intensity of the permanent magnet after the first demagnetization is greater than the set requirements, proceed to step (3) above and increase the subsequent demagnetization control voltage to demagnetize quantitatively again.

[0015] (5) The quantitative magnetization is completed.

[0016] This invention employs a method of first saturating magnetization and then quantitatively demagnetizing to achieve magnetization at a specified magnetic induction intensity, thus realizing highly stable magnetization at a specified magnetic induction intensity and demonstrating good practicality.

[0017] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for magnetizing a high-stability permanent magnet to a specified magnetic induction intensity, characterized in that, Includes the following steps: Step S1: Saturation magnetization: Based on the magnetic field strength required for permanent magnet saturation, control the external magnetic field to magnetize the permanent magnet to saturation; Step S2: Quantitative demagnetization: The permanent magnet is demagnetized quantitatively using an alternating magnetic field, while the magnetic induction intensity of the permanent magnet is detected. Step S3: If the magnetic induction intensity of the demagnetized permanent magnet meets the requirements, the process ends; Step S4: If the magnetic induction intensity of the demagnetized permanent magnet is less than the requirement, proceed to step S1 and reduce the control voltage V of the alternating magnetic field in step S2, thereby reducing the peak magnetic field intensity H0 of the demagnetizing alternating magnetic field and reducing the amount of demagnetization in one operation. The relationship between the coil magnetic field strength H and the control voltage V is as follows: ； Where: N is the number of turns of the coreless coil; Z is the impedance of the coreless coil; This is the length of the magnetic circuit; Step S5: If the magnetic induction intensity of the demagnetized permanent magnet is greater than the requirement, proceed to step S2.

2. The magnetization method for a specified magnetic induction intensity of a high-stability permanent magnet according to claim 1, characterized in that, In step S1, the external magnetic field is continuously increased until the magnetic induction intensity of the permanent magnet no longer increases. At this point, the external magnetic field strength is the magnetic field strength required for the permanent magnet to saturate.

3. The magnetization method for a specified magnetic induction intensity of a high-stability permanent magnet according to claim 2, characterized in that, In step S1, an external magnetic field with a magnetic field strength exceeding that required for permanent magnet saturation is used to magnetize the permanent magnet to saturation.

4. A magnetization method for a specified magnetic induction intensity of a high-stability permanent magnet according to any one of claims 1-3, characterized in that, In step S5, proceed to step S2 and increase the control voltage of the alternating magnetic field in step S2.

5. A magnetization method for a specified magnetic induction intensity of a high-stability permanent magnet according to any one of claims 1-3, characterized in that, In step S5, the process proceeds to step S1, and the control voltage of the alternating magnetic field in step S2 is reduced.

6. The magnetization method for a specified magnetic induction intensity of a high-stability permanent magnet according to claim 1, characterized in that, In steps S3 to S5, the magnetic induction intensity of the permanent magnet after the first demagnetization is determined to be equal to the set requirement.

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