WO2023119923A1

WO2023119923A1 - Soft magnetic material evaluation method and evaluation system

Info

Publication number: WO2023119923A1
Application number: PCT/JP2022/041698
Authority: WO
Inventors: 亮子荒木; 宇輝池田; 慎一加藤; 悠介安部; 悠介中村
Original assignee: 株式会社日立製作所
Priority date: 2021-12-23
Filing date: 2022-11-09
Publication date: 2023-06-29
Also published as: JP2023094120A

Abstract

To make it possible to evaluate the magnetic properties, especially a variation in coercive force, of a soft magnetic material used in electromagnets at a stage prior to being assembled into electronic lenses and other products, this soft magnetic material evaluation method involves: imaging the surface of the soft magnetic material by using an imaging unit to acquire a crystal structure image of the soft magnetic material; processing the obtained crystal structure image of the soft magnetic material by using an information processing system to evaluate the variation in the coercive force of the soft magnetic material; and displaying information pertaining to the variation of the coercive force of the evaluated soft magnetic material on a display terminal.

Description

SOFT MAGNETIC MATERIAL EVALUATION METHOD AND EVALUATION SYSTEM

The present invention relates to an evaluation method and evaluation system for soft magnetic materials.

Soft magnetic materials are processed into desired shapes and then combined with coils to form electromagnets, which are applied to various industrial and medical equipment. As the functions and accuracy required for these industrial equipment and medical equipment are becoming more sophisticated, the accuracy required for electromagnets is also becoming more sophisticated.

In the case of a scanning electron microscope (SEM) as an example of industrial equipment, the electromagnetic lens that controls the trajectory of primary and secondary electrons needs to be downsized and improve controllability, Stabilizing quality by minimizing variations in performance (instrumental differences) is required.

In Patent Document 1, it is described that the miniaturization of the motor is achieved by improving the magnetic flux density (saturation magnetic flux density) that can be excited.

JP 2011-174103 A

In order to minimize variations in performance between devices (instrumental differences) and stabilize quality, it is desirable to minimize variations in the characteristics of the magnetic materials (soft magnetic materials) used in electromagnets.

In order to reduce machine-to-machine variation and stabilize quality in scanning electron microscopes (SEMs), it is necessary to suppress variations in the magnetic properties of the electromagnet used in the electron lens (objective lens), especially in the coercive force. becomes important.

Patent Document 1 describes that the miniaturization of the motor is achieved by improving the magnetic flux density (saturation magnetic flux density) that can be excited. There is no mention of stabilizing the quality by suppressing the variation in performance between devices (instrumental difference) as much as possible.

The quality of soft magnetic materials can be controlled using mill sheets, but in order to evaluate the variation in coercive force (Hc) of soft magnetic materials, it is necessary to measure the magnetic properties, which takes time. . Moreover, if the electronic lens incorporated in the device does not exhibit the desired performance, a backtracking step of removing the electronic lens from the device is required, resulting in an increase in man-hours.

The present invention solves the above-described problems of the prior art, and makes it possible to evaluate the magnetic properties of soft magnetic materials used in electromagnets, particularly variations in coercive force, before they are assembled into products such as electronic lenses. An evaluation method and an evaluation system for soft magnetic materials are provided.

In order to solve the above problems, in the present invention, the structure of the soft magnetic material is imaged by an imaging unit to obtain a crystal structure image of the soft magnetic material, and the obtained crystal structure image of the soft magnetic material is obtained. The coercive force variation of the soft magnetic material is evaluated by processing it in the information processing system and comparing it with the separately measured coercive force variation value. This was used as an evaluation method for the soft magnetic material to be displayed.

Further, in order to solve the above-described problems, the present invention provides a soft magnetic material evaluation system comprising an imaging unit for capturing an image of the surface of the soft magnetic material to acquire a crystal structure image of the soft magnetic material, and An information processing system that processes the crystal structure image of the soft magnetic material captured by the imaging unit and evaluates the variation in the coercive force of the soft magnetic material, and the variation in the coercive force of the soft magnetic material evaluated by this information processing system. and a display terminal for displaying information about.

According to the present invention, the magnetic properties of the soft magnetic material used for the electromagnet, especially the variation in the coercive force, can be determined from the crystal structure image obtained by imaging the soft magnetic material, and the product can be assembled. In the previous stage, it was possible to evaluate the magnetic properties of soft magnetic materials, especially the variation in coercive force.

(a) is a grain boundary image obtained from an optical micrograph of the surface of the soft magnetic material, (b) is a boxplot showing the variation in grain size on the surface of the soft magnetic material, and (c) is the soft magnetic material. 4 is a histogram showing surface particle size distribution; 4 is a graph showing the relationship between the size of particles on the surface of a soft magnetic material and the coefficient of variation of coercive force. 1 is a block diagram showing a schematic configuration of an evaluation system for evaluating variations in coercive force of a soft magnetic material from surface grain size distribution information obtained by imaging the soft magnetic material according to an embodiment of the present invention; FIG. . It is a block diagram which shows the structure of the information processing part in the evaluation system based on the Example of this invention. FIG. 4 is a flowchart showing a procedure for creating a database for estimating a coercive force variation coefficient from information on the size of particles on the surface of a soft magnetic material according to an example of the present invention; FIG. 5 is a flow chart showing a procedure for estimating a coercive force variation coefficient from a crystal structure image of a soft magnetic material and determining whether or not the material can be accepted when the soft magnetic material according to the embodiment of the present invention is received. FIG. 5 is a flowchart showing a procedure for estimating a coercive force variation coefficient from a soft magnetic material crystal structure image, mapping and displaying coercive force variations according to an embodiment of the present invention. FIG. 5 is a diagram showing an example of a screen showing a result of estimating a coercive force variation coefficient from a soft magnetic material crystal structure image at the time of arrival of the soft magnetic material according to the embodiment of the present invention; FIG. 5 is a diagram showing an example of a screen showing a result of mapping coercive force variation by estimating a coercive force variation coefficient from a soft magnetic material crystal structure image according to an example of the present invention.

When permendur, an alloy of iron (Fe) and cobalt (Co), is used as the soft magnetic material, particles of various sizes appear on the surface of the soft magnetic material. FIG. 1(a) shows an example of a grain boundary image 11 of a permendur material.

In the grain boundary image 11 of FIG. 1(a), it can be seen that particles 111 with a relatively large particle size and particles 112 with a relatively small particle size are mixed on the surface of the material.

Fig. 1(b) shows the distribution of the particle size (particle diameter) in this grain boundary image 11 as a box plot: 12. In FIG. 1(b), the vertical axis indicates the particle size, and the unit is μm. From this figure, it can be seen that the 25% to 75% portion 121 of the particle size distribution ranges in size from 20 μm to 60 μm, the median size 122 is 35 μm, and the mean value 123 is 45 μm.

Graph 13 in FIG. 1(c) is a histogram showing the particle size distribution. The histogram of FIG. 1(c) is represented by a histogram 131 in which the particle size is divided by 10 μm pitch. From the histogram 131, two peaks can be confirmed at 20 μm to 40 μm and 60 μm. A curve 132 is obtained by fitting the distribution represented by the histogram 131 with a logarithmic normal distribution curve. It can be seen that there is a distribution peak between 20 μm and 30 μm, there is a large distribution in the range of 10 μm to 60 μm, and the largest one is distributed up to about 150 μm. However, it can be seen that this fitting cannot reproduce the two peaks that can be confirmed in the histogram. Also, two peaks cannot be represented in the boxplot described above.

As a result of evaluating various grain size distributions, it was found that there is a certain relationship between the grain size distribution and the coercive force variation (fluctuation range).

That is, as shown in the graph 21 of FIG. 2, the value obtained by dividing the first quartile in the distribution (variation range) of the grain size 22 appearing on the surface by the average value of the grain size and the coefficient of variation of the coercive force (coercive force It was found that there is a linear relationship represented by a straight line 23 between the standard deviation of .

That is, the smaller the value obtained by dividing the first quartile in the distribution of the particle size 22 by the average value of the particle size, the smaller the coefficient of variation of the coercive force and the smaller the variation in the coercive force. It was found that the larger the value obtained by dividing the first quartile by the average particle size, the larger the coefficient of variation of coercive force and the greater the variation in coercive force.

From this, the relationship between the particle size distribution obtained by analyzing the image obtained by examining the soft magnetic material with an optical microscope or magnetic force microscope (MFM) and the coercive force of the soft magnetic material By obtaining the relationship corresponding to the straight line 23 in FIG. , the variation in coercive force of this new soft magnetic material can be estimated.

The present invention has been made based on the above-mentioned new findings. With respect to soft magnetic materials used in electron lenses and the like, the soft magnetic materials can be detected from an image obtained by imaging the soft magnetic materials in place of magnetic measurement. This makes it possible to relatively easily determine variations in magnetic properties (coercive force) of materials.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In all the drawings for explaining this embodiment, parts having the same functions are denoted by the same reference numerals, and repeated explanation thereof will be omitted in principle.

However, the present invention should not be construed as being limited to the descriptions of the embodiments shown below. Those skilled in the art will easily understand that the specific configuration can be changed without departing from the idea or gist of the present invention.

FIG. 3 shows a schematic configuration of an evaluation system 100 for evaluating the magnetic properties of the soft magnetic material according to this example.

The evaluation system 100 according to the present embodiment includes a sample table 1 on which a sample 20 is placed, an imaging unit 2 for capturing an image of the surface of the sample 20 placed on the sample table 1, and an image of the sample 20 captured by the imaging unit 2. An information processing system 8 for processing and an image display terminal 9 for displaying information processed by the information processing system 8 are provided.

The imaging unit 2 includes a light source 3 and a half mirror 4 that reflects part of the light emitted from the light source 3 toward the sample 20 placed on the sample stage 1 and transmits part of the light reflected by the sample 20. , and a detector 5 for detecting the image of the surface of the sample 20 by receiving reflected light from the sample 20 that has passed through the half mirror 4 .

The information processing system 8 includes an information processing section 6 that receives and processes signals from the detector 5 that has imaged the surface of the sample 20 and an information storage section 7 that stores the information processed by the information processing section 6 .

The internal configuration of the information processing section 6 is shown in FIG. The information processing unit 6 includes a coercive force data storage unit 61, an image storage unit 62, a particle size measurement unit 63, a particle size analysis unit 64, a database 65, a coercivity variation coefficient calculation unit 66, a coercivity variation evaluation unit 67, and a network adapter. 68 and CPU 69 , which are connected to each other by a common line 60 and connected to a network 70 .

The coercive force data storage unit 61 stores the coercive forces of a plurality of points of the sample 20 obtained by measuring the sample 20 mounted on the sample table 1 with a coercive force measuring device (for example, a DC magnetization measuring device) (not shown). are stored in association with the sample 20.

The image of the sample 20 captured by the imaging unit 2 (corresponding to the grain boundary image 11 in FIG. 1) is stored in the image storage unit 62 . The particle size measuring unit 63 measures the size of particles (corresponding to the

particles

111 and 112 in FIG. 1) on the surface of the sample 20 from the image of the sample 20 stored in the image storage unit 62 . Here, for the measurement of the particle size on the surface of the sample 20 from the image of the sample 20, calculation is performed using general image analysis software.

The information on the particle size measured by the particle size measuring unit 63 is sent to the particle size analyzing unit 64, where the first quartile of the particle size distribution and the average value of the particle size are obtained. A value (hereinafter referred to as a particle size index value) is calculated by dividing the value of one quartile by the average value of the particle size.

On the other hand, in the coercive force variation coefficient calculation unit 66, the coercive force variation coefficient of the sample 20 (the standard deviation of the coercive force variation is divided by the average coercive force).

The particle size index value obtained by the particle size analysis unit 64 is sent to the database 65 in association with information on the coercive force variation coefficient calculated by the coercive force variation coefficient calculation unit 66 .

After a predetermined number of pieces of information on the particle diameter index value associated with the information on the coercive force variation coefficient are stored in the database 65, these data are sent to the coercive force variation evaluating unit 67, where the coercive force variation evaluating unit 67 By performing regression analysis on variations in combinations of coercive force variation coefficients and particle size index values, relationships between coercive force variation coefficients and particle size index values, such as the straight line 23 in FIG. .

Each operation of the coercive force data storage unit 61, the image storage unit 62, the particle size measurement unit 63, the particle size analysis unit 64, the database 65, the coercive force variation coefficient calculation unit 66, and the coercive force variation evaluation unit 67 is performed by the common line 60. It is controlled by the connected CPU 69 .

A procedure for creating a database for evaluating the coercive force variation of the sample 20 from the crystal structure image of the sample 20 using such an evaluation system 100 will be described with reference to the flowchart of FIG.

Since data is acquired for a plurality of samples in creating the database, n is set to 1 in S501, and the coercive force of the first sample 20 is measured at a plurality of points using coercive force measuring means (not shown), The data is stored in the coercive force data storage unit 61 (S502), and the coercive force variation coefficient calculating unit 66 calculates the standard deviation and average value of the measured coercive force.

Next, the sample 20 whose coercive force has been measured is placed on the sample table 1 of the evaluation system 100 shown in FIG. (S503). Specifically, the sample 20 placed on the sample table 1 is irradiated with light from the light source 3, and the crystal structure image thereof is detected by the detector 5. Stored in the storage unit 62 .

Next, in the grain size measurement unit 63 of the information processing unit 6, the crystal structure image data stored in the image storage unit 62 is processed, the grain size included in this crystal structure image is measured, and the grain size analysis unit In step 64, the particle size distribution is analyzed, and the particle size in the first quartile and the average particle size are obtained (S504).

Next, it is determined whether the value of n has reached the preset N (S505), and if it has not reached N (No), 1 is added to n (S508) and the process returns to S502.

On the other hand, if the value of n reaches the preset N (Yes), proceed to the next step, evaluate the relationship between the coefficient of variation of coercive force and the first quartile/average particle size, and A relationship between the coercive force variation coefficient and the particle diameter index value, such as the straight line 23 in (S506), is stored in the database 65 (S507).

Next, a method for estimating the variation in coercive force from the crystal structure image of the sample 20 made of a soft magnetic material using the database thus created will be described.

FIG. 6 shows the flow of processing when the present invention is applied to an acceptance inspection performed when purchasing soft magnetic material from a material manufacturer.

First, for the received soft magnetic material, the imaging unit 2 of the evaluation system 100 shown in FIG. Using the data, the particle size analysis unit 64 analyzes the particle size (S602), obtains the first quartile and average particle size (S603), and stores the coercive force variation coefficient and particle size index value stored in the database. (corresponding to the straight line 23 in FIG. 2), the coercive force variation coefficient is determined, and it is determined whether or not the determined coercive force variation coefficient is smaller than a preset reference value (S604).

As a result of the determination, if the calculated coercive force variation coefficient is larger than the preset reference value (NG), it is determined that the acceptance reference value is not satisfied, and the incoming soft magnetic material is returned to the manufacturer (S605). .

On the other hand, if the obtained coefficient of variation of coercive force is smaller than the preset reference value (OK), it satisfies the acceptance reference value, so delivery of the received soft magnetic material is approved (S606).

Regarding the delivered soft magnetic material, depending on the magnitude of the coercive force variation coefficient, the one with the coercive force variation coefficient A judgment that the coercive force variation coefficient is closer to 0 than the reference value and the one with the coercive force variation coefficient equal to the reference value Soft magnetic materials with a coercive force variation coefficient A determination are used in processes corresponding to products that require a relatively small range of coercive force variation. After the manufacturing process (S607), the product is assembled in the product assembly process (S608).

On the other hand, the soft magnetic material determined to have a coercive force variation coefficient B is adopted in a process corresponding to a product that can have a relatively large variation range of coercive force, and undergoes the part manufacturing process (S609). The product is assembled in the product assembly process (S610).

In this case, since it is known whether the soft magnetic material used in the assembled product is A grade or B grade, the size of the coercive force variation range required for each product Depending on the application, the product applied can be varied.

Next, the procedure for evaluating the coercive force variation coefficient at the stage of processing the soft magnetic material delivered after passing the acceptance inspection described in FIG. 6 will be described with reference to FIG.

Even if the soft magnetic material that has passed the acceptance inspection described in FIG. There may be a portion where the coercive force variation coefficient is large) and a portion where the coercive force variation coefficient is small (a portion where the coercive force variation is small).

That is, even among the members evaluated as A in the acceptance inspection described in FIG. Among them, there is a possibility that there is a part where the coercive force variation coefficient of the A evaluation level is small.

Therefore, as shown in FIG. 7, before the soft magnetic material is processed, the distribution of the coercive force variation coefficient is examined over the entire surface of the soft magnetic material to be processed. It is determined whether the coercive force variation is large or small. As a result, it is possible to distinguish between a region to be processed for a product that requires a small variation in coercive force and a region to be processed for a product that is allowed to have a relatively large variation in coercive force.

The flow of FIG. 7 will be described below.
First, the entire surface of the soft magnetic material to be processed is sequentially imaged with the field size of the detector 5 in the imaging unit 2 of the evaluation system 100 shown in FIG. An image is comprehensively acquired for the entire surface of the soft magnetic material (S701).

Next, the acquired image is processed by the information processing unit 6, and the grain size of the soft magnetic material to be processed is analyzed for each image (each imaging region) (S702), and in each image (each imaging region) The first quartile of particle size and the average particle size are obtained, and the particle size index value obtained by dividing the first quartile by the average particle size value is extracted (S703).

Next, based on the particle size index value obtained in S703, each image (each imaged area), and it is determined whether the calculated coercive force variation coefficient is larger or smaller than a preset threshold value (S704).

As a result of the determination, if the coercive force variation coefficient is smaller than the preset threshold value (YES), it is determined that the coercive force variation is small within the range of the image (each imaging region) (S705), and the coercive force variation coefficient is If it is larger than the preset threshold value (NO), it is determined that the coercive force variation is large within the range of the image (each imaging area) (S706).

Next, for each of the areas determined to have small coercive force variations (S705) and those determined to have large coercive force variations (S706), create a coercive force variation mapping of the area analyzed for coercive force (S707), The result is displayed on a GUI (Graphic User Interface) (S708).

FIG. 8 shows an example of a GUI 80 that displays the results of the inspection performed during the material acceptance inspection described in the flowchart of FIG.

The GUI 80 includes an information input area 82, an acquired image display area 83 for displaying an acquired image of the surface of the material, and a grain size included in the image obtained by processing the acquired grain boundary image of the material in the information processing unit 6. Particle size distribution display area 84 for displaying information about the coercive force variation coefficient correlation expression display area 85 for displaying information about the variation coefficient of the coercive force of the sample, Analysis result display area 86 for displaying analysis results, and judgment results A determination result display area 87 is provided.

The information input area 82 includes a material name input section 821 for inputting the material name of the material to be inspected, a composition ratio data input section 822 for inputting data on the composition ratio of the material input in the material name input section 821, and a material name input section. A mill sheet number input section 823 for inputting the number of the mill sheet attached to the material input to 821, a coercive force input section 824 for inputting the coercive force of the material to be inspected displayed on the mill sheet, and a magnetic flux density input section for inputting the magnetic flux density. 825, a magnetic permeability input unit 826 for inputting the magnetic permeability, and a DB calling unit 827 for calling information stored in the database 65.

An acquired image display area 83 displays an image 831 of the material surface acquired by the imaging unit 2 and stored in the image storage unit 62 of the information processing unit 6. A particle size distribution display area 84 displays an acquired image display area. The particle size distribution of the material surface in the image 831 measured by the particle size measurement unit 63 of the information processing unit 6 and analyzed by the particle size analysis unit 64 from the image 831 labeled in 83 is shown in FIG. A graph display area 841 for displaying data corresponding to a histogram 131 and a curve 132 obtained by fitting the data of this histogram 131 with a logarithmic normal distribution curve, and a box and whisker showing the distribution of particle sizes displayed by this histogram. A graphical boxplot display area 842 is provided.

In the coercive force variation coefficient correlation expression display area 85, data corresponding to the material input in the material name input section 821 among the data stored in the database 65 by clicking the DB call section 827 in the information input area 82 is displayed. A graph 851 representing the relationship between the particle size index value obtained by dividing the first quartile of the particle size by the average value of the particle size and the coercive force variation coefficient as shown in FIG. The selected material name 854 is displayed. The graph 851 shows a straight line 852 obtained by linearly approximating the relationship between the value obtained by dividing the first quartile of the particle size by the average value of the particle size and the coercive force variation coefficient, and the coercive force variation coefficient at the time of acceptance inspection. A straight line 853 indicates a reference value for the determination of .

In the analysis result display area 86, an image 831 of the surface of the material displayed in the acquired image display area 83 is measured by the particle size measurement unit 63 of the information processing unit 6, analyzed by the particle size analysis unit 64, and is analyzed by the coercive force variation evaluation unit. A graph 861 displaying the results 863 evaluated in 67 on the same graph as the graph 851, an average value display portion 865 displaying the average value of the particle size corresponding to the evaluation results 863, and the first quartile of the particle size distribution. A first quartile data display 866 is provided for displaying data. The graph 861 displays a straight line 862 corresponding to the straight line 852 of the graph 851 and a straight line 864 corresponding to the straight line 853 indicating the reference value for determination of the coercive force variation coefficient at the time of acceptance inspection.

In the determination result display area 87, a coercive force variation display portion 871 for displaying the variation in coercive force corresponding to the evaluation result 863 indicated in the graph 861 in the analysis result display area 86, and a soft magnetic material to be inspected this time. An adaptable product display section 872 for displaying the name of the product to be processed and incorporated with the material is displayed, and the material evaluated by the coercive force variation evaluation section 67 is applied to the product displayed in the adaptable product display section 872. and a DB registration button 874 for registering the judgment result in the database 65 .

In this way, since the evaluation result of the coercive force variation range of the material obtained based on the crystal structure image obtained by imaging the surface of the material when the material is received is displayed on the GUI 80, the conventional coercive force measuring means can be used. In a comparatively short period of time compared to the case of using a measuring device, it is possible to easily determine whether or not the material can be accepted, and furthermore, to establish an optimum processing policy.

FIG. 9 shows a GUI 90 showing the result of evaluating the coercive force variation coefficient performed at the stage of processing the soft magnetic material delivered after passing the acceptance inspection described in the flowchart of FIG.

Similar to the GUI 80 described with reference to FIG. 8, the GUI 90 shown in FIG. Particle size distribution display area 94 for displaying information on the particle size contained in the processed image, coercive force variation coefficient correlation formula 95 for displaying information on the coefficient of variation of the coercive force of the sample, and analysis result display area 96. , and a determination result display area 97 for displaying determination results.

In the portion corresponding to the analysis result display area 86 displaying the analysis results in FIG. 8, a coercive force variation mapping display area 86 showing the variation in coercive force at locations corresponding to a plurality of images is displayed.

The information input area 92 includes a material name input section 921 for inputting the material name of the material to be inspected, a composition ratio data input section 922 for inputting data on the composition ratio of the material input in the material name input section 921, and a material name input section. A mill sheet number input section 923 for inputting the number of the mill sheet attached to the material input to 921, a coercive force input section 924 for inputting the coercive force of the material to be inspected displayed on the mill sheet, and a magnetic flux density input section for inputting the magnetic flux density. 825, a magnetic permeability input unit 926 for inputting magnetic permeability, and a DB calling unit 927 for calling information stored in the database 65.

In the acquired image display area 93, an image display section 931 for displaying the image of the material surface acquired by the imaging section 2 and stored in the image storage section 62 of the information processing section 6, and an area for displaying this image are set. A display area setting portion 932 is displayed.

In the particle size distribution display area 94, the particle surface of the material measured by the particle size measurement unit 63 of the information processing unit 6 from the image displayed on the image display unit 931 of the acquired image display area 93 and analyzed by the particle size analysis unit 64 is displayed. A graph display area 941 for displaying data corresponding to the histogram 131 as described in FIG. , and a boxplot display area 942 for displaying the distribution of particle sizes displayed by this histogram in a boxplot.

However, when an all area button 962 in the coercive force variation mapping display area 96, which will be described later, is set, the graph display area 941 displays the grain size distribution of the entire imaged area of the material to be inspected as a histogram. A curve obtained by fitting a logarithmic normal distribution curve corresponding to the histogram is displayed. The boxplot display area 942 also displays data corresponding to the distribution of particle diameters in the entire area.

In the coercive force variation coefficient correlation equation and analysis result display area 95, the material name entered in the material name input section 921 among the data stored in the database 65 by clicking the DB call section 927 in the information input area 92 is displayed. A graph 951 representing the relationship between the particle size index value obtained by dividing the first quartile of the particle size by the average value of the particle size and the coefficient of variation of the coercive force as shown in FIG. The material name 955 entered in section 921 is displayed.

The graph 951 shows a straight line obtained by linearly approximating the relationship between the particle size index value obtained by dividing the first quartile of the particle size by the average value of the particle size and the coercive force variation coefficient stored in the database 65. 952 and data 953 corresponding to a plurality of regions marked in the coercive force variation mapping display area 96 are displayed. In the graph 951, a straight line 954 is displayed as a reference value for determination of the coercive force variation coefficient at the time of acceptance inspection.

In the coercive force variation mapping display area 96, the results of analyzing the images of the material surface in a plurality of regions are displayed, for example, in a graph 951 according to the magnitude of the coercive force variation for each region corresponding to the image captured by the imaging unit 2. Designate a mapping display portion 961 that distinguishes between the case above the indicated straight line 954 (large coercive force variation) and the case below it (small coercive force variation), and the area to be marked on this mapping display portion 961. , an all area button 962 and a specified area button 963 are displayed.

When the all area button 962 is clicked, the image display unit 931 displays the evaluation result of the coercive force variation for the entire area captured by the imaging unit 2 for the material corresponding to the mill sheet input to the mill sheet number input unit 923. When the specified area button 963 is clicked, the evaluation result of the coercive force variation in the area set by the display area setting section 932 and its surrounding area is displayed.

In the determination result display area 97, a coercive force variation display portion 971 for displaying the coercive force variation in the region indicated in the mapping display portion 961 of the coercive force variation mapping display area 96, and a soft magnetic material to be inspected this time. is displayed, and the material evaluated by the coercive force variation evaluation unit 67 is the material to be applied to the product displayed in the applicable product display unit 972. A judgment display portion 973 for displaying the result of judging whether or not to accept the request, and a DB registration button 974 for registering the judged result in the database 65 are provided.

In this way, by displaying on the GUI 90 the evaluation result of the coercive force variation range of the material obtained based on the crystal grain size image obtained by imaging the surface of the soft magnetic material before processing the material, It is possible to evaluate the variation in coercive force individually for each, and then process it.

As a result, according to this embodiment, the range of variation in the coercive force of the soft magnetic material is guaranteed when the product is assembled into a processed product. It is possible to prevent the backtracking process of disassembling a once-assembled product and replacing parts caused by a defect (when the variation range of coercive force is larger than the reference value).

In addition, according to the present embodiment, the variation in coercive force is individually evaluated for each material before being processed and assembled into a product, so it is possible to ensure stable quality of the assembled product.

In the present embodiment, the method of evaluating the variation in coercive force before processing the soft magnetic material was explained, but the variation in coercive force was evaluated after processing the soft magnetic material and before incorporating it into the product. may be evaluated. By evaluating after processing, the variation in coercive force can be evaluated in a state closer to the product.

When this embodiment is applied to an electron lens, the variation in the coercive force of the soft magnetic material can be evaluated before the coil is wound. It is possible to prevent the occurrence of backtracking processes for subsequent products.

Also, the case of permendur material as the soft magnetic material has been described, but iron or electromagnetic steel sheets can also be used.

Although the invention made by the present inventor has been specifically described above based on the embodiments, it goes without saying that the invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the invention. stomach. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. Moreover, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

DESCRIPTION OF SYMBOLS 1... Sample stand 2... Imaging part 3... Light source 4... Half mirror 5... Detector 6... Information processing part 7... Information storage part 8... Information processing system 9... Image display terminal 60... Common line 61 Coercive force data storage unit 62 Image storage unit 63 Particle size measurement unit 64 Particle size analysis unit 65 Database 66 Coercive force variation coefficient calculation unit 67 Coercive force variation evaluation Part 68... Network adapter 69... CPU 70...

Network

80, 90... GUI

Claims

Acquiring a crystal structure image of the soft magnetic material by imaging the surface of the soft magnetic material with an imaging unit,
processing the acquired crystal structure image of the surface of the soft magnetic material with an information processing system to evaluate the variation in the coercive force of the soft magnetic material,
A method for evaluating a soft magnetic material, characterized in that information about the variation in coercive force of the evaluated soft magnetic material is displayed on a display terminal.
The evaluation method for the soft magnetic material according to claim 1,
The information on the variation in the coercive force of the soft magnetic material displayed on the display terminal includes a mapping display of the variation in the coercive force of the soft magnetic material by dividing it into each region of the soft magnetic material. A method for evaluating a soft magnetic material characterized by:
A method for evaluating a soft magnetic material according to claim 1,
As information about the variation in the coercive force of the soft magnetic material displayed on the display terminal, the crystal structure image of the surface of the soft magnetic material imaged by the imaging unit and the surface of the soft magnetic material A method for evaluating a soft magnetic material, further comprising information on the distribution of grain sizes on the surface of the soft magnetic material obtained by processing a crystal structure image.
A method for evaluating a soft magnetic material according to claim 1,
A method for evaluating a soft magnetic material, wherein the information about the variation in the coercive force of the soft magnetic material displayed on the display terminal includes an evaluation result of the variation in the coercive force of the soft magnetic material. .
The evaluation method for the soft magnetic material according to claim 1,
In the information processing system, the grain size of the soft magnetic material is measured by processing the crystal structure image of the surface of the soft magnetic material imaged by the imaging unit by the image processing unit, and the variation of the grain size is calculated. The relationship between the variation in coercive force and the variation in particle diameter measured in advance for a soft magnetic material different from the soft magnetic material is stored in a storage unit, and the soft magnetic material obtained by the image processing unit The coercive force variation evaluation unit evaluates the coercive force of the soft magnetic material based on the data on the variation in particle size of the material and the relationship between the variation in coercive force and the variation in particle size stored in the storage unit. A method for evaluating a soft magnetic material, characterized by evaluating the variation of.
an imaging unit that captures an image of the surface of a soft magnetic material to acquire a crystal structure image of the soft magnetic material;
an information processing system that processes the crystal structure image of the surface of the soft magnetic material captured by the imaging unit and evaluates variations in coercive force of the soft magnetic material;
A coercive force evaluation system for a soft magnetic material, comprising: a display terminal for displaying information about variations in the coercive force of the soft magnetic material evaluated by the information processing system.
A coercive force evaluation system for a soft magnetic material according to claim 6,
The display terminal is characterized in that, as the information about the variation in the coercive force of the soft magnetic material, the variation in the coercive force of the soft magnetic material is mapped and displayed for each region of the soft magnetic material. Coercivity evaluation system for soft magnetic materials.
A coercive force evaluation system for a soft magnetic material according to claim 6,
The display terminal displays the crystal structure image of the surface of the soft magnetic material imaged by the imaging unit and the crystal structure of the surface of the soft magnetic material as information about the variation in the coercive force of the soft magnetic material. A coercive force evaluation system for a soft magnetic material, further displaying information on the distribution of grain sizes on the surface of the soft magnetic material obtained by processing a tissue image.
A coercive force evaluation system for a soft magnetic material according to claim 6,
The display terminal displays an evaluation result of the coercive force variation of the soft magnetic material as the information about the coercive force variation of the soft magnetic material. rating system.
A coercive force evaluation system for a soft magnetic material according to claim 6,
The information processing system processes the crystal structure image of the surface of the soft magnetic material captured by the imaging unit, measures the grain size of the soft magnetic material, and obtains the variation in the grain size. and a storage unit for storing the relationship between the variation in coercive force and the variation in grain size measured in advance for a soft magnetic material different from the soft magnetic material, and the soft magnetic material obtained by the image processing unit. A coercive force variability of the soft magnetic material is evaluated based on the data of the variability of the grain size of the material and the relationship between the coercive force variability and the grain size variability stored in the storage unit. A coercive force evaluation system for a soft magnetic material, comprising: a magnetic force variation evaluation unit.