JP2020030191A - Ceramic inner structure observation device and inner structure analysis system, ceramic inner structure observation method and inner structure analysis method, and ceramic manufacturing method - Google Patents

Abstract

To enable in-situ observation of a defatting step and a sintering step of ceramic, and elucidation of change in inner structure.SOLUTION: For a compact 1 which is produced by molding a raw material of ceramic and which is being subjected to heat treatment in a heat treatment furnace 11, light in an infrared region is applied from the outside of the heat treatment furnace 11 using an optical interference tomographic image generation device 20 to generate an optical interference tomographic image by optical interference tomography. Thus, an inner structure of the compact in a heat treatment process of ceramic in the heat treatment furnace can be observed as the optical interference tomographic image generated by the optical interference tomographic image generation device 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ceramic internal structure observation device and an internal structure observation analysis system, a ceramic internal structure observation method and an internal structure analysis method, and a ceramic manufacturing method.

  It is known that the internal structure of ceramics greatly changes during the process from raw material powder to slurry, compact, and sintered compact. Conventionally, a method using an optical microscope (for example, see Non-Patent Document 1) and a method using X-ray CT (for example, see Non-Patent Documents 2 and 3) have been used for observing the internal structure of ceramics.

  It is known that the characteristics of ceramics are governed by the internal structure of the ceramics. Therefore, if the process of forming the structure in the ceramics process chain from raw materials to the final product, ceramics, can be accurately grasped and the structure can be controlled, ceramics with excellent functions and high reliability can be manufactured. . In addition, if it is possible to evaluate the structure of a slurry, a molded body, a sintered body, etc. that changes every moment during the manufacturing process in real time by utilizing such an observation method of the structure forming process, it is necessary to rely on visual observation or craftsmanship. In addition, it is possible to detect the cause of the formation of the non-uniform structure in the relatively previous step and remove it.

  Furthermore, if 100% inspection of the internal structure of the final product can be performed at high speed, with high resolution and in a wide range at low cost, the reliability of the product can be improved and the cost required for the inspection can be reduced.

  Thus, it is extremely important to dynamically and three-dimensionally observe and scientifically understand the structure forming process in the ceramic manufacturing process in order to improve the yield and reliability of the ceramic.

  On the other hand, there are many control factors for each unit operation in the ceramics manufacturing process. For example, in the dispersion of ceramic fine particles, the type and amount of the dispersant correspond to control factors. Dispersion of the ceramic fine particles in the dispersion medium is a complicated phenomenon involving adsorption of the dispersant to the ceramic fine particles, wettability of the dispersion medium to the ceramic fine particles, and the like. For this reason, control factors for preparing the slurry have been apparently optimized based on intuition and experience.

  Also, phenomena related to the interface between the particles and the liquid phase, such as the affinity for the solvent and the adsorption behavior of the dispersant, should be different for each ceramic fine particle. Therefore, considering the subsequent molding process, it is necessary to optimize the control factors in consideration of the viscosity of the slurry, the solid content in the slurry, the organic matter (binder, plasticizer, lubricant, etc.) contained in the slurry, and the like. .

  When the sheet-shaped molded body is dried, the structure should be dynamically changed from a structure in which the ceramic fine particles are dispersed in the liquid to a structure in which the solids are in contact with each other. This change is similar to aggregation. If, at the same time as drying of the compact, the changes in the internal structure of the compact can be accurately grasped and the control factors for the formation of the structure can be elucidated scientifically, the drying temperature for obtaining a homogeneous compact without cracks and deformation, It is believed that time and atmosphere can be determined more analytically. Furthermore, even in the process of sintering a compact, which consumes a lot of energy, the temperature rise profile largely depends on an artistic setting. If the control factors in the sintering process can be scientifically elucidated and optimized appropriately, the amount of energy consumption can be reduced, and the cost can be reduced.

  As described above, if the understanding of the structure forming process in the ceramics manufacturing process and the chemical elucidation of the control factors can be realized, it is possible to systematize the ceramics manufacturing process technology. Then, through optimization of the entire ceramics process chain, it is possible to solve various technical problems which are obstacles to the spread of ceramics. As a result, in the production of ceramics, it is possible to realize an improvement in yield, a reduction in cost, an increase in reliability, and the like.

  Conventionally, although there has been a high-temperature microscope (for example, see Patent Literature 1) as an apparatus for observing a material surface at a high temperature, the inside cannot be observed.

  In addition, X-ray CT was used as a device for observing the inside of a substance. However, since it takes time to measure, it is not possible to measure in real time changes in internal structure due to sintering, degreasing, dehydration, etc. that occur during firing. could not.

  Further, the optical coherence tomography is one of the methods for observing the inside of a material at high speed and high resolution, but has been used only for observation at room temperature (for example, see Patent Document 2).

Japanese Utility Model Publication No. 5-36356 JP-A-2002-310899

K.Uematsu, J.-Y.Kim, Z.Kato, N.Uchida, K.Saito, ”Direct Observation Method for InternaL Structure of Ceramic Green Body -ALumina Green Body as an ExampLe”, The Ceramic Society of Japan, 199 0, 98 [5], p515-516 T.Hondo, Z.Kato, S.Tanaka, ”Enhancing the contrast of Low-density packing regions in images of ceramic powder compacts using a contrast agent for micro-X-ray computer tomography”, JorunaL of the Ceramic Society of Japan , 2014,122 [7], p574-576 D. Bernard et al. "First didect 3D visualization of microstructrural evolutions during sintering through X-ray computed microtomgraphy" Acta Materialia. 53 (2005) 121-128

  As described above, the characteristics of ceramics greatly depend on the internal structure, but the structure changes for each manufacturing process such as mixing, molding, degreasing, and firing. In particular, in the degreasing process and the firing process, which are performed by heating at a high temperature, large changes in the substance such as melting, evaporation, thermal decomposition, oxidation, and sintering shrinkage of the added organic substance occur, and the volume change also occurs. It can happen.

  The internal structure of the ceramic may be non-uniform due to, for example, non-uniform density and porosity, coarse particles, pores, cracks, impurities, and second phases. It is known that when these are present inside the ceramics, they can be a starting point of destruction, which causes a reduction in strength and significantly lowers the mechanical reliability of the ceramics. Such heterogeneity of the internal structure of ceramics has optical heterogeneity.

  Therefore, it is important to understand and control the structural change of the molded body due to degreasing and firing, that is, the optically inhomogeneous state, in producing an excellent ceramic.

  Accordingly, an object of the present invention is to provide a high-speed and high-resolution three-dimensional observation of internal structure changes at high temperatures, which cannot be observed conventionally, simultaneous measurement of changes in internal structures and densities, The purpose of the present invention is to enable simultaneous measurement of changes in internal structure and changes in weight in situ.

  That is, an object of the present invention is to provide an internal observation method (OCT (Optical Coherence Tomography: Optical Coherence Tomography)) capable of observing the internal structure of an opaque substance using optical interference, thereby realizing structural changes in a high-temperature environment in real time. By observing, it is possible to observe in-situ during the degreasing process and firing process of ceramics, and to clarify the change in internal structure, the internal structure observation device and internal structure analysis system of ceramics, the internal structure observation method and internal structure analysis of ceramics It is an object of the present invention to provide a method and a method for producing ceramics.

  Other objects of the present invention and specific advantages obtained by the present invention will become more apparent from the description of the embodiments described below.

  The present invention relates to an apparatus for observing the internal structure of ceramics, which comprises a heat treatment furnace for performing a heat treatment on a molded body formed by molding a ceramic raw material, and An optical coherence tomographic image generating unit for performing optical coherence tomography by irradiating light in an infrared region from the optical coherence tomographic image, and as an optical coherence tomographic image generated by the optical coherence tomographic image generating unit, It is characterized in that the internal structure of the compact can be observed during the heat treatment process of the ceramics by the heat treatment furnace.

  The apparatus for observing the internal structure of a ceramic according to the present invention may be configured such that, for example, the optical axis of the light in the infrared region irradiated on the compact by the optical coherence tomographic image generation unit is set to be 1 to the normal direction of the observation surface of the compact. It may be configured to be inclined at a predetermined angle within an angle range of 10 to 10 °.

  In addition, the ceramic internal structure observation device according to the present invention includes, for example, a posture adjustment mechanism that varies a holding posture of the optical coherence tomographic image generation unit, and the posture adjustment mechanism is configured to irradiate an infrared region that irradiates the molded body. The optical coherence tomographic image generation unit can be held in a state where the optical axis of light is inclined at a predetermined angle within the range of 1 to 10 ° with respect to the normal direction of the observation surface of the molded body. .

  Further, the apparatus for observing the internal structure of a ceramic according to the present invention includes, for example, a posture adjusting mechanism that changes a holding posture of the molded body in the heat treatment furnace, and an infrared region irradiated by the optical coherence tomographic image generation unit. The molded body can be held by the attitude adjustment mechanism in a state where the normal direction of the observation surface with respect to the optical axis of light is inclined at a predetermined angle within the above-described angle range of 1 to 10 °.

  Further, the apparatus for observing the internal structure of a ceramic according to the present invention further includes, for example, a weighing device including a weighing dish on which the compact is placed in the heat treatment furnace, and forming the ceramic in a heat treatment process of the ceramics by the heat treatment furnace. The weight change can be measured together with the observation of the structure inside the body.

  The present invention also provides a system for analyzing the internal structure of ceramics, which comprises a heat treatment furnace for performing a heat treatment on a compact formed by molding a ceramic raw material, and a heat treatment furnace for treating the compact during heat treatment in the heat treatment furnace. An optical coherence tomographic image generating apparatus for generating optical coherence tomographic images by irradiating light in the infrared region from outside of the apparatus and an image analysis process for the optical coherence tomographic images generated by the coherent tomographic image generating apparatus And an optical analysis heterogeneity in the internal structure of the formed body during the heat treatment process of the ceramics by using the optical coherence tomographic image generated by the coherence tomographic image generation device. It is characterized in that image analysis processing is performed to determine whether a state has occurred.

  The internal structure analysis system for ceramics according to the present invention is, for example, such that the optical axis of light in the infrared region irradiated on the molded body by the optical coherence tomographic image generating apparatus is 1 to the normal direction of the observation surface of the molded body. It may be configured to be inclined at a predetermined angle within an angle range of 10 to 10 °. .

  Further, the ceramic internal structure analysis system according to the present invention includes, for example, a posture adjustment mechanism that varies the holding posture of the optical coherence tomographic image generation device, and the posture adjustment mechanism allows an infrared region of the molded body to be irradiated to the compact. The optical coherence tomographic image generating apparatus can be held in a state where the optical axis of light is inclined at a predetermined angle within the above-mentioned angle range of 1 to 10 ° with respect to the normal direction of the observation surface of the molded body. .

  Furthermore, the internal structure analysis system for ceramics according to the present invention includes, for example, a posture adjustment mechanism that varies a holding posture of the compact in the heat treatment furnace, and an infrared region irradiated by the optical coherence tomographic image generation device. The molded body can be held by the attitude adjustment mechanism in a state where the normal direction of the observation surface with respect to the optical axis of light is inclined at a predetermined angle within the above-described angle range of 1 to 10 °.

  Furthermore, the internal structure analysis system for ceramics according to the present invention further includes a weighing device including a weighing dish on which the compact is placed in the heat treatment furnace, and the inside of the compact during the heat treatment of the ceramics by the heat treatment furnace. It is possible to measure the weight change together with the observation of the structure.

  The present invention also relates to a method for observing the internal structure of ceramics, which comprises a heat treatment step of subjecting a molded body obtained by molding a raw material of ceramics to a heat treatment with a heat treatment furnace; An optical coherence tomographic image generating step of performing optical coherence tomography by irradiating light in an infrared region from outside of the heat treatment furnace to generate an optical coherence tomographic image, and optical interference generated in the optical coherence tomographic image generating step As a tomographic image, it is possible to observe the internal structure of the compact during the heat treatment process of the ceramics.

  The present invention also relates to a method for analyzing the internal structure of ceramics, comprising: a heat treatment step of subjecting a molded body obtained by molding a raw material of ceramics to a heat treatment by a heat treatment furnace; An optical coherence tomographic image generating step of performing optical coherence tomography by irradiating light in an infrared region from outside the furnace and generating an optical coherence tomographic image, and an image of the optical coherence tomographic image generated in the optical coherence tomographic image generation step An image analysis processing step of performing an analysis processing, wherein in the image analysis processing step, an image analysis processing is performed to determine whether an optically inhomogeneous state occurs in a structure inside the molded body in a heat treatment process of the ceramics. I do.

  Further, the present invention relates to a method for producing ceramics, comprising: a heat treatment step of subjecting a molded body obtained by molding a raw material of ceramics to a heat treatment by a heat treatment furnace; An optical coherence tomographic image generating step of performing optical coherence tomography by irradiating light in an infrared region from outside of the optical coherence tomographic image and using the optical coherence tomographic image generated in the optical coherence tomographic image generating step An image analysis processing step of performing an image analysis processing to determine whether an optical inhomogeneous state has occurred in the structure inside the molded body in the heat treatment step of the ceramics, and based on the image analysis result in the image analysis processing step, And a control step of changing conditions for heat treatment of the ceramics by the heat treatment furnace.

  According to the present invention, an optical coherence tomographic image generating apparatus that generates an optical coherence tomographic image by an internal observation method (OCT (optical coherence tomography)) capable of observing the internal structure of an opaque substance using optical interference is heat-treated. By attaching it to the device and devising the observation method, it is possible to observe the structural changes in a high-temperature environment in real time, so that the in-situ observation and clarification of internal structural changes during the degreasing and sintering processes of ceramics are possible. It is possible to provide a ceramic internal structure observation apparatus and an internal structure analysis system, a ceramic internal structure observation method and an internal structure analysis method, and a ceramic manufacturing method. When firing while performing, after the ceramic is densified, firing can be stopped before the heterogeneous structure appears, such as ceramic It is possible to optimize based on experimental facts, not intuition and manufacturing experience.

1 is a block diagram illustrating a configuration of a ceramic internal structure analysis system to which the present invention has been applied. It is a schematic diagram which shows the structure of the optical coherence tomographic image generation apparatus in the said internal structure analysis system. It is a flowchart showing the procedure of the ceramics internal structure observation method performed in the ceramics internal structure analysis system. In the system for analyzing the internal structure of ceramics, the normal θ of the observation surface of the molded body during firing and the angle θ formed by the optical axis of the light in the infrared region to be irradiated are 1.3 °, 5.2 °, 8.2 °. 4A to 4C are optical coherence tomographic images obtained by in-situ observation of a molded body in a heat treatment furnace by an optical coherence tomographic image generating apparatus for the experimental examples 1) to 3), wherein (A) shows an angle θ = 1. Optical coherence tomographic image of experimental example 1) at 3 °, (B) Optical coherent tomographic image of experimental example 2) at angle θ = 5.2 °, and (C) Experimental example 3 at angle θ = 8.2 °. 6) is an optical coherence tomographic image. In the internal structure analysis system for ceramics described above, the angle θ between the normal axis of the observation surface of the molded body during firing and the optical axis of light in the infrared region to be irradiated was set to 0 °, 0.4 °, 12.1 °. Regarding Experimental Examples 4) to 6), optical coherence tomographic images obtained by in-situ observation of a molded body in a heat treatment furnace by an optical coherence tomographic image generating apparatus, and (A) is an experimental example in which the angle θ = 0 ° 4B) Optical coherence tomographic image, (B) Optical coherence tomographic image of experimental example 5) with angle θ = 0.4 °, (C) Optical coherence tomographic image of experimental example 6) with angle θ = 12.1 ° It is an image. In the internal structure analysis system for ceramics, the optical coherence tomographic image is obtained by in-situ observation of the internal structure of the alumina molded body in the heat treatment furnace by the optical coherence tomographic image generation apparatus, and (A) shows the image before firing. It is an optical coherence tomographic image of a molded body, (B) is 1400 ° C., (C) is 1500 ° C., (D) is 1600 ° C., (E) is an optical coherence tomographic image of the molded body after holding at 1600 ° C. for 5 minutes. is there. It is a flowchart showing the procedure of the ceramics internal structure analysis method performed in the ceramics internal structure analysis system. 1 is a block diagram illustrating a configuration of a ceramic internal structure analysis system to which the present invention has been applied. It is a flowchart which shows the procedure of the analysis processing performed with respect to the optical coherence tomographic image produced | generated by the said optical coherence tomographic image generation apparatus in the said ceramics internal structure analysis system. It is a flowchart which shows the procedure of the machine learning process of the speckle noise elimination method performed by the learning device in the said ceramic internal structure analysis system. It is an image which shows the example of a speckle noise removal process, (A) is an output image, (B) is an input image, (C) is an image from which an input image is extracted by trimming, (D) is an OCT observation image. . It is a flowchart which shows the procedure of the speckle noise removal processing which uses the original image several times and is performed when detecting the pores in a molded object in the said ceramic internal structure analysis system. It is an image which shows the example of a speckle noise removal process, (A) is an output image, (B) is an input image, (C) is an image from which an input image is extracted by trimming, (D) is an OCT observation image. . It is a flowchart which shows the procedure of the speckle noise removal process which uses the original image several times and is performed when detecting the heterogeneous area | region in a molded object in the said ceramic internal structure analysis system. It is an image which shows the example of a speckle noise removal process, (A) is an output image, (B) is an input image, (C) is an image from which an input image is extracted by trimming, (D) is an OCT observation image. . It is a flowchart which shows the procedure of the speckle noise removal process which uses the original image several times and is performed when detecting the heterogeneous area | region in a molded object in the said ceramic internal structure analysis system. It is a block diagram showing composition of a manufacturing system of ceramics to which the present invention is applied. It is a flowchart showing the procedure of the manufacturing method of the ceramics performed in the above-mentioned ceramics manufacturing system. 1 is a block diagram illustrating a configuration of a ceramic internal structure analysis system to which the present invention has been applied. FIG. 4 is a process chart showing a procedure of an internal structure analysis method performed in the ceramic internal structure analysis system. In the system for analyzing the internal structure of ceramics, an optical coherence tomographic image of a molded article obtained by in-situ observation of a degreasing process of ceramics, wherein (A) is an optical coherence tomographic image obtained at 30 ° C. ) Is an optical coherence tomographic image obtained at 50 ° C., (C) is an optical coherence tomographic image obtained at 158 ° C., (D) is an optical coherence tomographic image obtained at 304 ° C., and (E) is an image at 600 ° C. It is the obtained optical coherence tomographic image. It is a block diagram showing composition of a manufacturing system of ceramics to which the present invention is applied. It is a flowchart showing the procedure of the manufacturing method of the ceramics performed in the above-mentioned ceramics manufacturing system.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that common constituent elements will be described with common reference symbols attached in the figure. Further, it is needless to say that the present invention is not limited to the following examples, and can be arbitrarily changed without departing from the gist of the present invention.

  The present invention is applied to, for example, a ceramic internal structure analysis system 100 having a configuration as shown in the block diagram of FIG.

  The ceramic internal structure analysis system 100 includes a heat treatment apparatus 10, an optical coherence tomographic image generation apparatus 20, and an image analysis processing apparatus 30.

  The heat treatment apparatus 10 in the internal structure analysis system 100 includes a heat treatment furnace 11 composed of a high-temperature electric furnace for performing a heat treatment such as a degreasing treatment or a sintering treatment on a compact 1 formed by molding a ceramic raw material. The operation of the heat treatment furnace 11 can be controlled by a control unit 17 having a measurement / control unit 15 using a processing unit (central processing unit) and an information processing unit 16.

  The optical coherence tomographic image generation device 20 in the internal structure analysis system 100 includes, for example, a light source 21, a half mirror 22, a reference mirror 23, and a detector 24 as shown in the schematic diagram of FIG. And a camera head unit 25 including an optical interference system constituted by a light source 21, a detector 24, and an information processing unit 26.

  The light source 21 irradiates the sample 1 with light in the infrared region.

  In the internal structure analysis system 100, the sample 1 is the compact 1 that is being heat-treated in the heat treatment furnace 11, that is, ceramics.

  In general, what is obtained by a molding process, what is degreased is called a molded body, and what is sintered by firing at high temperature is called a sintered body. Call body.

  The light source 21 emits light having a center wavelength from 700 nm (nanometers) to 2000 nm and reflected by the ceramics according to the present embodiment. The light reflected by the ceramics is, for example, light that is not absorbed by the ceramics.

  The half mirror 22 is provided on the optical path of the light emitted from the light source 21. The half mirror 22 is arranged such that a surface 22a on the light source 21 side is inclined at an angle of 45 ° toward the light source 21 with respect to the optical path.

  The half mirror 22 divides the light emitted from the light source 21 into irradiation light for irradiating the sample (molded body) 1 and reference light incident on the reference mirror 23. Then, the half mirror 22 reflects the divided irradiation light and makes it incident on the sample (molded body) 1. The half mirror 22 transmits the divided reference light and makes it enter the reference mirror 23.

  The reference mirror 23 is provided on an optical path of light emitted from the light source 21.

  The reference mirror 23 reflects the reference light transmitted through the half mirror 22 and returns the reflected light to the half mirror 22. Therefore, the reference mirror 23 is provided so as to face the half mirror 22.

  The reference mirror 23 is movable along the optical path of the light emitted from the light source 21. That is, the distance between the reference mirror 23 and the half mirror 22 can be adjusted. Instead of making the reference mirror 23 movable, a similar function may be performed by using a variable wavelength light source.

  The detectors 24 are provided on the optical path of return light obtained by irradiating the sample (molded body) 1 with irradiation light and on the optical path of reference light. The reference light is reflected by the reference mirror 23, returns to the half mirror 22, and is further reflected by the half mirror 22.

  The half mirror 22 and the reference mirror 23 of the optical coherence tomographic image generation device 20 constitute an interference optical system.

  The detector 24 is for observing the interference light between the return light and the reference light.

  Here, the internal structure analysis system 100 includes a stand 40 having a support 41 erected on a base 41, and the heat treatment furnace 11 of the heat treatment apparatus 10 is installed on the base 41. A camera head unit 25 including an interference optical system composed of a half mirror 22 and a reference mirror 23 of the optical coherence tomographic image generation device 20 is provided at a front end of an arm 43 extending laterally from an upper end of the support column 42. The holding posture is variably adjusted at a position above the heat treatment furnace 11 on the base 41 by the head holding unit 44 thus obtained.

  The heat treatment furnace 11 of the heat treatment apparatus 10 can place the molded body 1 on the sample table 12 in the furnace by opening the upper lid 14 having the window 14A, and outside the furnace with the upper lid 14 closed. The molded article 1 in the furnace can be observed through the window 14A.

  That is, the stand 40 is capable of moving and adjusting the camera head unit 25 of the optical coherence tomographic image generating apparatus 20 in three-dimensional (X, Y, Z) directions, and is capable of adjusting the rotation angle position around the X axis and the Y axis. The head holding unit 44 variably adjusts the holding posture at a position above the heat treatment furnace 11 on the base 41.

  The heat treatment furnace 11 of the heat treatment apparatus 10 is configured to hold the molded body 1 on the sample stage 12 by operating a sample stage arm 13 provided with the sample stage 12 at the tip from outside the heat treatment furnace 11. Is provided.

In the internal structure analysis system 100, the optical axis of light in the infrared region irradiated on the molded body 1 from the camera head unit 25 of the optical coherence tomographic image generation device 20 is measured by the method of the observation surface 1 </ b> A of the molded body 1. The optical coherence tomographic image generation device 20 generates an optical coherence tomographic image in a state where the optical coherence tomographic image generation device 20 is inclined at a predetermined angle θ within an angle range of 1 to 10 ° with respect to the line direction. Here, both the holding posture of the camera head unit 25 and the holding posture of the molded body 1 on the sample stage 12 are variably adjustable. However, by providing one of the posture adjusting mechanisms, the molded body 1 can be adjusted. Can be inclined with respect to the normal direction of the observation surface 1 </ b> A of the molded body 1.

  The observation or photographing of the internal structure of the sample (molded body) 1 by the optical coherence tomographic image generation device 20 is performed as follows.

  That is, the light source 21 emits light in the infrared region. Here, the light in the infrared region is light having a center wavelength from 700 nm to 2000 nm, and is light reflected by ceramics.

  The half mirror 22 divides the light emitted from the light source 21 into irradiation light for irradiating the sample (molded body) 1 and reference light incident on the reference mirror 23. The half mirror 22 reflects the divided irradiation light and makes it incident on the sample (molded body) 1. Further, the half mirror 22 transmits the divided reference light and makes it enter the reference mirror 23. That is, the irradiation light split by the half mirror 22 is applied to the sample (molded body) 1 in the furnace through the window 14A provided in the upper lid 14 of the heat treatment furnace 11 of the heat treatment apparatus 10.

  Irradiation light that has entered the sample (molded body) 1 is reflected at an interface having a difference in refractive index, such as the surface and internal structure of the sample (molded body) 1, and returns as light to the surface of the sample (molded body) 1, The light is emitted from the observation surface 1A. The return light emitted from the observation surface 1A is incident on the half mirror 22 of the optical coherence tomographic image generation device 20 through the window 14A of the heat treatment furnace 11 of the heat treatment device 10.

  The return light obtained by irradiating the sample (molded body) 1 with the irradiation light and the reference light reflected back by the reference mirror 24 are superimposed again on the half mirror 22. At this time, if the return light from the sample (molded body) 1 and the reference light from the reference mirror 24 pass at the same distance, the two lights strengthen each other. On the other hand, if the return light from the sample (molded body) 1 and the reference light from the reference mirror 24 have a different distance and the phases of the light are reversed, the two lights cancel each other out.

  Here, the distance between the reference mirror 24 and the half mirror 22 is adjusted by moving the reference mirror 24 constituting the optical interference system, and a position where the two lights interfere with each other and are strengthened on the detector 24 is observed. From this observation, it is possible to know at which depth in the sample (molded body) 1 the reflective surface is located. Thereby, the internal structure of the sample (molded body) 1 can be observed. Further, by imaging the inspection result, the internal structure of the sample (molded body) 1 can be photographed.

  That is, the optical coherence tomographic image generation apparatus 20 transmits the light in the infrared region emitted from the light source 21 of the optical coherence tomographic image generation unit 27 to the heat treatment furnace 11 through the optical interference system included in the camera head unit 25. The sample (molded body) 1 being heat-treated in the heat treatment furnace 11 is irradiated from the window 14A to return light from the sample (molded body) 1 obtained by the optical interference system included in the camera head 25. Detecting the interference light with the reference light by the detector 24 of the optical coherence tomographic image generation unit 27 performs optical coherence tomography of the sample (molded body) 1, and is obtained as a detection output by the detector 24. An optical coherent tomographic image is generated from the information processing unit 26 using, for example, a personal computer (PC) from the distance image information based on the interference light. As a method of generating a tomographic image by the optical coherence tomographic image generation unit 27 of the optical coherence tomographic image generation device 20, a known tomographic image generation method in optical coherence tomography can be used.

  The direction of the tomographic image generated by the optical coherence tomographic image generation unit 27 is not limited to a specific direction. For example, the optical coherence tomographic image generation device 20 three-dimensionally scans the sample (molded body) 1, and the information processing unit 26 of the optical coherence tomographic image generation unit 27 generates a three-dimensional image of the sample (molded body) 1. You may do so. Thus, the optical coherence tomographic image generation unit 27 can generate a tomographic image at an arbitrary position and in an arbitrary direction within the scan range of the sample (molded body) 1.

  By using the optical coherence tomographic image generation apparatus 20 having the above-described configuration, a change in the internal structure at a high temperature, which cannot be observed conventionally, can be observed in three dimensions at high speed and high resolution. In addition, not only the internal structure but also a change in external dimensions can be measured, and a change in density can be measured simultaneously with the internal structure. That is, observation or imaging of the internal structure of the sample (molded body) 1 can be performed in real time. Further, the observation of the internal structure of the sample (molded body) 1 can be recorded in a moving image.

  In the optical coherence tomographic image generating apparatus 20, the light from the light source 21 is a light in the infrared region having a center wavelength of 700 nm to 2000 nm and reflected by the sample (molded body) 1 as a sample (molded body). The sample (molded body) 1 made of ceramics is observed by irradiating 1) and moving the reference mirror 24. This makes it possible to three-dimensionally observe the internal structure of ceramics that could not be observed conventionally. When a variable wavelength light source is used instead of making the reference mirror 24 movable, the sample (molded body) 1 is observed by adjusting the wavelength and intensity of light emitted from the variable wavelength light source. Is also good.

  In the ceramic internal structure analysis system 100, the heat treatment apparatus 10 and the optical coherence tomographic image generation apparatus 20 can observe the internal structure of the ceramic according to the procedure shown in the process diagram of FIG.

  FIG. 3 is a process chart showing a procedure of a method for observing the internal structure of ceramics, which is performed in the internal structure analysis system 100 for ceramics.

  In the heat treatment step S <b> 1, a heat treatment such as a degreasing treatment or a sintering treatment is performed on a molded body 1 formed by molding a ceramic raw material by a heat treatment furnace 11 of a heat treatment apparatus 10.

  In the optical coherence tomographic image generation step S2, the optical coherence tomographic image generation device 20 applies infrared rays to the molded body 1 being heat-treated in the heat treatment step S1 from the outside of the heat treatment furnace 11 through the window 14A. Optical coherence tomography is performed by irradiating the light of the area to generate an optical coherence tomographic image.

  In the heat treatment apparatus 10 and the optical coherence tomographic image generation apparatus 20 in the ceramic internal structure analysis system 100, a heat treatment furnace 11 performs a heat treatment such as a degreasing treatment or a sintering treatment on the molded body 1 obtained by molding the ceramic raw material. And a light interference process for irradiating the compact 1 under heat treatment in the sintering process S1 with light in the infrared region from outside the heat treatment furnace 11 to perform optical coherence tomography and generate optical coherence tomographic images. A tomographic image generation step S2, wherein the optical coherence tomographic image generated in the optical coherence tomographic image generation step S2 is a method for observing the internal structure of a ceramic body in which the internal structure of the compact during the heat treatment process of the ceramic can be observed. Can be performed.

  In the internal structure analysis system 100 for ceramics, the heat treatment apparatus 10 performs a heat treatment such as a degreasing treatment or a sintering treatment on the molded body 1 formed by molding the ceramic raw material by a heat treatment furnace 11, and The optical coherence tomographic image generating apparatus 20 generates an optical coherence tomographic image by irradiating the compact 1 being sintered in the heat treatment furnace 11 with light in an infrared region from outside the heat treatment furnace 11 to perform optical coherence tomography. The heat treatment apparatus 10 and the optical coherence tomographic image generation apparatus 20 use the optical coherence tomographic image generated by the optical coherence tomography image generation unit 27 as the optical coherence tomographic image inside the compact during the heat treatment of the ceramics by the heat treatment furnace 11. Functions as an internal structure observation device for ceramics whose structure can be observed.

  Here, when an optical coherence tomographic image is generated by the optical coherence tomographic image generation apparatus 20, the optical axis of light in the infrared region irradiated from the camera head unit 25 to the molded body 1 is measured by the method of the observation surface 1A of the molded body 1. If the direction coincides with the line direction, noise appears in the optical coherence tomographic image (OCT) image due to strong reflection from the surface of the observation surface 1A, but this noise can be greatly reduced by inclining the image.

  FIG. 4 shows that in the ceramic internal structure analysis system 100, the angle θ between the normal direction of the observation surface 1A of the molded body 1 during firing and the optical axis of the light in the infrared region to be irradiated is 1.3 °, 5 °. Regarding Experimental Examples 1) to 3) at 2 ° and 8.2 °, the optical coherence tomographic image obtained by in-situ observation of the molded body 1 in the heat treatment furnace 11 by the optical coherence tomographic image generation device 20 was used. is there. In FIG. 4, (A) is an optical coherence tomographic image of Experimental Example 1) at an angle θ = 1.3 °, (B) is an optical coherent tomographic image of Experimental Example 2) at an angle θ = 5.2 °, (C) is an optical coherence tomographic image of Experimental Example 3) at an angle θ = 8.2 °.

  FIG. 5 shows that in the ceramic internal structure analysis system 100, the angle θ between the normal line method of the observation surface 1A of the molded body 1 during firing and the optical axis of the light in the infrared region to be irradiated is 0 °, 0. It is the optical coherence tomographic image obtained by in-situ observation of the molded object in a heat treatment furnace with the optical coherence tomographic image generation apparatus about Experimental Examples 4) to 6) at 4 ° and 12.1 °. In FIG. 5, (A) is an optical coherence tomographic image of Experimental Example 4) at an angle θ = 0 °, (B) is an optical coherent tomographic image of Experimental Example 5) at an angle θ = 0.4 °, and (C). Is an optical coherence tomographic image of Experimental Example 6) at an angle θ = 12.1 °.

  That is, the optical coherence tomographic image generated by the optical coherence tomographic image generation device 20 for the compact 1 being heat-treated in the heat treatment furnace 11 of the heat treatment device 10 is an experiment shown in FIGS. As in the optical coherence tomographic images of Examples 1) to 3), the angle θ between the normal direction of the observation surface 1A of the molded body 1 and the optical axis of the light in the infrared region to be irradiated is 1.3 °. At 2 ° and 8.2 °, the noise was extremely small. On the other hand, as in the optical coherence tomographic images of Experimental Examples 4) to 6) shown in FIGS. When the angle θ between the normal line method of the observation surface 1A and the optical axis of the light in the infrared region to be irradiated is 0 °, 0.4 °, 12.1 °, a large amount of noise appears.

  As described above, the optical coherence tomographic image for generating an optical coherence tomographic image by irradiating the compact 1 being heat-treated in the heat treatment furnace 11 with light in an infrared region from outside the heat treatment furnace 11 to generate an optical coherence tomography image In order to make it possible to observe the internal structure of the compact during the heat treatment process of the ceramics by the heat treatment furnace 11 by the generating device 20, an infrared region irradiated onto the compact 1 from the camera head 25 of the optical coherence tomographic image generating device 20. In the state where the optical axis of the light is inclined by a predetermined angle θ within an angle range of 1 to 10 ° with respect to the normal direction of the observation surface 1A of the molded body 1, noise is generated by the optical coherence tomographic image generation device 20. A small optical coherence tomographic image can be generated.

  Here, in the ceramic internal structure analysis system 100, the optical coherence tomographic image obtained by in-situ observation of the internal structure of the alumina molded body in the heat treatment furnace 11 by the optical coherence tomographic image generation device 20 is shown in FIG. (A) to (E).

6 (A) to 6 (E) show 0.2 wt% MgO powder (500A, Ube Material) with respect to Al ₂ O ₃ powder (TMDAR, Daimei Chemical Co., Ltd.) having an average particle size of 0.1 μm. After the addition of paraffin as a binder to the raw material powder to which the raw material powder is added and granulation by sieve, a molded body is obtained by uniaxial molding and CIP molding, and the degreased molded body 1 is set in the heat treatment furnace 11 of the heat treatment apparatus 10. The optical coherence tomographic image obtained by continuously performing OCT observation by the optical coherence tomographic image generation device 20 while raising the temperature to 1600 ° C. at 100 ° C. per minute and holding at 1600 ° C. for 5 minutes. is there. In FIG. 6, (A) is an optical coherence tomographic image of the compact before firing, (B) is 1400 ° C., (C) is 1500 ° C., (D) is 1500 ° C., (E) is 1600 ° C. for 5 minutes. It is an optical coherence tomographic image of the compact 1 in each stage after holding.

  Furthermore, the dimensions of the molded body 1 were measured from the obtained optical coherence tomographic image obtained by the optical coherence tomographic image generation device 20, and the shrinkage ratio and the relative density could be calculated.

  In the internal structure analysis system 100 for ceramics, the optical coherence tomographic images of FIGS. 6A to 6E obtained by the optical coherence tomographic image generation device 20 are side cross sections near the center of the compact 1 in each firing process. Is shown. In these optical coherence tomographic images, for example, a region where the reflection of light generated in an inhomogeneous region having a difference in refractive index such as pores and alumina is more brightly displayed. In any of the optical coherence tomographic images, despite being observed at a high temperature, it is not affected by radiation at all, and the internal structure of the molded body 1 is clearly observed as in the case of room temperature. It is observed that the whole body contracts. Observation of the molded body 1 before firing revealed that bright island-shaped regions were distributed, and thus it is considered that in the molding stage, heterogeneity, that is, distribution in density occurred. On the other hand, since a bright and conspicuous region was not observed from 1400 ° C. to 1500 ° C. (relative density of 90% obtained from the dimensions), the large density distribution was resolved and the internal structure was considered to be relatively homogeneous. . However, at 1600 ° C. (99% relative density), a bright and dark island-like region of about 100 to 200 μm appeared. A dark area means that there are few areas to be reflected, and is a higher density area. Although the internal structure became uniform as a whole with the passage of time, a bright region was newly generated afterwards, which is considered to be due to locally grown pores due to the inhomogeneity of the molded body.

  As described above, the generation of the optical coherence tomographic image by the optical coherence tomographic image generating apparatus 20 is an effective method for in-situ observation of the sintering process of ceramics. It can be clarified that they occur and grow and disappear.

  In the ceramic internal structure analysis system 100, the image analysis processing device 30 performs an image analysis process on the optical coherence tomographic image generated by the optical coherence tomographic image generation device 20. An integration unit 32 is provided.

  The image analysis processing device 30 uses the optical coherence tomographic image generated by the optical coherence tomographic image generation device 20 to generate an optically inhomogeneous state in the internal structure of the compact during the degreasing process and the sintering process of ceramics. The image processing unit 31 performs an analysis process as to whether or not the image data is present.

  In the ceramic internal structure analysis system 100, optical interference for generating an optical coherence tomographic image by an internal observation method (OCT (Optical Coherence Tomography)) capable of observing the internal structure of an opaque substance using optical interference. By attaching the tomographic image generation device 20 to the heat treatment device 10, it is possible to clarify the internal structure change in a high-temperature environment in real time, and further, for example, by performing sintering while performing in-situ observation of the sintering process. After the ceramics are densified, firing can be stopped before the appearance of a heterogeneous structure. For example, it is possible to optimize the ceramics based on experimental facts rather than intuition and experience.

  In the ceramic internal structure analysis system 100, the heat treatment apparatus 10, the optical coherence tomographic image generation apparatus 20, and the image analysis processing apparatus 30 can analyze the internal structure of the ceramic according to the procedure shown in the process diagram of FIG. it can.

  FIG. 7 is a process chart showing the procedure of a method for analyzing the internal structure of ceramics, which is performed in the internal structure analysis system 100 for ceramics.

  That is, in the heat treatment step S <b> 1, a heat treatment is performed by the heat treatment furnace 11 of the heat treatment apparatus 10 on the molded body 1 formed by molding the ceramic raw material.

  In the optical coherence tomographic image generation step S2, the optical coherence tomographic image generation device 20 applies infrared rays to the molded body 1 being heat-treated in the heat treatment step S1 from the outside of the heat treatment furnace 11 through the window 14A. Optical coherence tomography is performed by irradiating the light of the area to generate an optical coherence tomographic image.

  In the analysis processing step S3, analysis processing is performed on the optical coherence tomographic image generated in the optical coherence tomographic image generation step S2 to determine whether an optically inhomogeneous state has occurred in the structure inside the compact during the heat treatment of the ceramics.

  In the ceramic internal structure analysis system 100, an optical coherence tomographic image obtained by in-situ observation of the molded body 1 being heat-treated by the heat treatment furnace 11 of the heat treatment apparatus 10 by the optical coherence tomography image generation apparatus 20 is performed by an image analysis processing apparatus. By performing an analysis process at 30 to determine whether an optically inhomogeneous state has occurred, it is possible to determine whether the sintered state of the compact 1 in the furnace is good or not.

  For example, with respect to the optical coherence tomographic image near the center of the compact 1 in each of the firing steps shown in FIGS. 6A to 6E, the image analysis processing device 30 analyzes whether an optically inhomogeneous state has occurred. By performing the processing, it is possible to analyze a situation in which the entire compact 1 shrinks with a rise in temperature, and determine an optimum sintering condition.

  Here, the image analysis processing device 30 may have a learning function of a learning device 35, like the ceramic internal structure analysis system 100A shown in the block diagram of FIG.

  FIG. 8 is a block diagram showing a configuration of a ceramic internal structure analysis system 100A to which the present invention is applied.

  The Lamix internal structure analysis system 100A includes a heat treatment apparatus 10, an optical coherence tomographic image generation apparatus 20, an image analysis processing apparatus 30, and a learning apparatus 35.

  The image analysis processing device 30 includes a first communication unit 310, a first storage unit 320, and a first control unit 330. The first control unit 330 includes an analysis processing unit 331, a speckle noise removal processing unit 332, and a non-uniform state detection unit 333. The learning device 35 includes a second communication unit 350, a second storage unit 360, and a second control unit 370. The second storage unit 360 includes a learning data storage unit 361. The second control unit 370 includes a learning data acquisition unit 371 and a machine learning unit 372.

  The heat treatment apparatus 10 and the optical coherence tomographic image generation apparatus 20 in the ceramic internal structure analysis system 100A are the same as the heat treatment apparatus 10 and the optical coherence tomographic image generation apparatus 20 in the ceramic internal structure analysis system 100 shown in FIG. 8 are given the same reference numerals and description thereof is omitted.

  The internal structure analysis system 100A performs optical coherence tomography by irradiating light in the infrared region from outside the heat treatment furnace 11 into the heat treatment furnace 11 of the heat treatment apparatus 10 by the optical coherence tomographic image generation apparatus 20. As a result, a tomographic image of the sample, that is, the molded body 1 during the heat treatment is acquired, and the state of the molded body 1 is analyzed based on the luminance in the tomographic image.

  The image analysis processing device 30 is configured using a computer such as a personal computer (PC) or a workstation (Workstation).

  The first communication unit 310 of the image analysis processing device 30 communicates with another device. In particular, the first communication unit 310 communicates with the optical coherence tomographic image generation device 20 and receives tomographic image data obtained as a measurement result of the molded body 1 by the optical coherence tomography image generation device 20. Further, the first communication unit 310 communicates with the second communication unit 350 of the learning device 35 to transmit tomographic image data of the molded body 1 to the learning device 35. Further, the first communication unit 310 communicates with the second communication unit 350 of the learning device 35 and receives the learning result of the speckle noise (Speckle Noise) removal processing by the learning device 35 from the learning device 35.

  The first storage section 320 stores various data. The first storage unit 320 is configured using a storage device included in the image analysis processing device 30.

  The first control unit 330 controls various units of the image analysis processing device 30 to perform various processes. The first control unit 330 is configured by a CPU (Central Processing Unit, central processing unit) included in the image analysis processing device 30 reading a program from the first storage unit 320 and executing the program.

The image analysis processing device 30 and the learning device 35 may be configured as one device, for example, configured using the same computer.
The operation of the internal structure analysis system 100A will be described.
FIG. 9 is a flowchart showing a procedure of an analysis process performed in the ceramic internal structure analysis system 100A.

  The internal structure analysis system 100A performs an analysis process on the optical coherence tomographic image generated by the optical coherence tomographic image generation device 20 according to the procedure shown in the flowchart of FIG.

  That is, when the image analysis processing is started in the image analysis processing device 30, first, the analysis processing unit 331 starts a loop L1 for performing processing for each type of optically inhomogeneous state (step S21). Examples of types of optical heterogeneity include, but are not limited to, pores and cracks.

  Next, the speckle noise removal processing unit 332 of the analysis processing unit 331 performs speckle noise removal processing on the optical coherence tomographic image generated by the optical coherence tomographic image generation device 20 (Step S22).

  The learning device 35 determines the speckle noise removal method by performing machine learning for each state of the molded body and for each type of optically inhomogeneous state. Examples of the type of the state of the molded body include, but are not limited to, the relative density and the remaining amount of the organic substance.

  The speckle noise elimination processing unit 332 includes, among the speckle noise elimination methods determined by the learning device 35, the structure inside the molded body in the tomographic image to be analyzed and the optical heterogeneity to be treated in the loop L1. A speckle noise removal method according to the type of state is used.

  Alternatively, the learning device 35 may select a speckle noise removal method for each state of the molded body, for each type of optically inhomogeneous state, and according to the type of the material constituting the ceramic. For example, the user may input the type of the substance constituting the ceramics to the learning device 35, and the learning device 35 may select a speckle noise removal method according to the user input.

  Next, the non-uniform state detection unit 333 of the analysis processing unit 331 detects an optically non-uniform state in the sample (molded body) 1 using the tomographic image after noise removal obtained in step S22 (step S23). ). Specifically, the non-uniform state detection unit 333 detects an optically non-uniform part in the tomographic image after noise removal.

  When detecting an optically inhomogeneous portion, the inhomogeneous state detection unit 333 determines the type of the optically inhomogeneous state based on the size and shape of the optically inhomogeneous portion.

  Then, the analysis processing unit 331 performs termination processing of the loop L1 (Step S24).

  Specifically, the analysis processing unit 331 determines whether or not the processing of the loop L1 has been performed for all types of the optically inhomogeneous state.

  If it is determined that there is a type of unprocessed optically inhomogeneous state, the process returns to step S21, and the processing of the loop L1 is continuously performed for the type of unprocessed optically inhomogeneous state.

  On the other hand, when it is determined that the processing of the loop L1 has been performed for all types of the optically inhomogeneous state, the analysis processing unit 331 ends the loop L1.

  When the loop L1 ends in step S24, the analysis processing unit 331 ends the analysis processing illustrated in the flowchart of FIG.

  FIG. 10 is a flowchart showing a procedure of a machine learning process of the speckle noise removing method executed by the learning device 35 in the ceramic internal structure analysis system 100A.

  In the internal structure analysis system 100A, the machine learning unit 372 of the learning device 35 performs a machine learning process of a speckle noise removing method according to, for example, a procedure of a process illustrated in a flowchart of FIG.

  The learning data storage unit 361 of the learning device 35 stores learning data for each state of the compact and for each type of optically inhomogeneous state.

  The machine learning unit 372 performs the learning process shown in the flowchart of FIG. 10 for each state of the molded body and for each type of the optically inhomogeneous state, and for each state of the molded body and for the type of the optically inhomogeneous state. A speckle noise removal method is determined for each case.

  That is, the machine learning unit 372 starts a loop L2 that performs a process for each state of the compact (step S31).

  Further, the machine learning unit 372 starts a loop L3 that performs a process for each type of the optically inhomogeneous state (step S32).

  Next, the machine learning unit 372 acquires learning data (step S33). Specifically, the machine learning unit 372 learns the internal structure of the molded object to be processed in the loop L2 and the learning data of the type of the optically inhomogeneous state to be processed in the loop L3. Read from the data storage unit 381.

  Next, the machine learning unit 372 machine-learns the speckle noise removal method using the learning data obtained in step S33 (step S34). By this machine learning, the machine learning unit 372 generates the speckle noise in the case of the structure inside the molded body to be processed in the loop L2 and the type of the optically inhomogeneous state to be processed in the loop L3. Determine the removal method.

  Then, the machine learning unit 372 performs termination processing of the loop L3 (Step S35). Specifically, the machine learning unit 372 determines whether or not the processing of the loop L3 has been performed for all types of the optically inhomogeneous state.

  If it is determined that there is a type of unprocessed optically inhomogeneous state, the process returns to step S32, and the processing of the loop L3 is continuously performed on the type of unprocessed optically inhomogeneous state.

  On the other hand, when it is determined that the processing of the loop L3 has been performed for all types of the optically inhomogeneous state, the machine learning unit 372 ends the loop L3.

  When the loop L3 ends in step S35, the machine learning unit 372 performs termination processing of the loop L2 (step S36). The machine learning unit 372 determines whether or not the processing of the loop L2 has been performed for all the structures inside the compact. When it is determined that there is an unprocessed structure inside the formed body, the process returns to step S31, and the processing of the loop L2 is continuously performed on the unprocessed structure inside the formed body.

  On the other hand, when it is determined that the processing of the loop L2 has been performed for all the structures inside the molded body, the machine learning unit 372 ends the loop L2.

  When the loop L2 ends in step S36, the machine learning unit 372 ends the learning processing illustrated in the flowchart of FIG.

  Alternatively, the machine learning unit 372 may perform machine learning for each state of the molded body, for each type of the optically inhomogeneous state, and for each type of the substance constituting the ceramic. For this purpose, the machine learning unit 372 performs, in the learning process shown in the flowchart of FIG. 10, a loop for each state of the molded body and a loop for each type of optically inhomogeneous state, The processing of a triple loop including this loop may be performed.

  The machine learning unit 372 uses, for example, learning data including a weight image in addition to an original image and a target image, and uses both a genetic algorithm (Genetic Algorithm; GA) and genetic programming (Genetic Programming; GP). Machine learning by evolutionary calculation is performed to determine the processing procedure for speckle noise removal processing.

  In the genetic programming, the same processing as in the case of the genetic algorithm is performed on a tree whose operation is represented by a tree structure.

  The speckle noise removal processing unit 332 performs the speckle noise removal processing shown in accordance with the processing procedure determined by the machine learning unit 372.

  However, as described above, the machine learning algorithm used by the machine learning unit 372 is not limited to a specific one.

  In the internal structure analysis system 100 for ceramics, the speckle noise removal processing unit 332 performs each state of the molded body and each type of the optically inhomogeneous state in step S22 in the analysis processing shown in the flowchart of FIG. As one of the speckle noise removal processing, for example, extraction is performed from an image as shown in FIG. 11C in which an OCT observation image shown in FIG. 11D is subjected to contrast averaging (leveling) processing. By using the original image shown in FIG. 11B obtained by trimming the region as an input image a plurality of times and performing speckle noise removal processing according to the procedure shown in the flowchart of FIG. The target image as shown in (1) can be obtained.

  The speckle noise removal processing unit 332 of the machine learning unit 372 performs the speckle noise removal processing according to, for example, the procedure shown in the flowchart of FIG.

  In the case where the machine learning unit 392 detects pores in the molded body, the processing procedure of FIG. 12 is determined by machine learning.

  The speckle noise removal processing unit 293 performs the speckle noise removal processing of FIG. 12 on the input image [000] shown in FIG. 11B according to the processing procedure determined by the machine learning unit 392. Obtain the target image as shown in FIG.

  In the speckle noise removal processing shown in the flowchart of FIG. 12, [Min] is the minimum processing for outputting the minimum value of the pixels in a 3 × 3 window centered on the target pixel for each pixel.

  [Exp] is a 3 × 3 window expansion (Expansion) process.

  [BDA] is a BinarizationDiscriminantAnalysis process for performing binarization based on a threshold calculated using a discriminant analysis method.

  [Gau] is a Gaussian filter for smoothing an image using a 3 × 3 window Gaussian filter.

  [LEX] is LinearExpand (255 × (f−15) / (255−15 ×)) processing.

  [Ave] is Average ((f1 + f2) / 2) processing.

  [LBW] is a LowAreaPerBoxW process that leaves a low filling factor (less than 0.9) for the circumscribed rectangle.

  [BoS] is BoundedSum (f1 + f2) processing.

  [BoP] is BoundedProd (f1 + f2-255) processing.

  [Open] is Opening (minimum value filter → maximum value filter) processing.

  [Mea] is an averaging (Mean) process of outputting, for each pixel, an average value of pixels in a 3 × 3 window centered on the pixel of interest.

  [VIn] is the dispersion image hmax.

  [Gam] is Gamma ((γ = 2.0) pow (f / 255, 1 / γ) × 255) processing for brightening an image.

  [LCo] is LinearContract ((255−15 × 2) × f / 255 + 15) processing.

  [ReC] is ReduceColor (f / 16 × 16 + 8) processing.

  [000] is an input image, that is, an image before speckle noise removal.

  Further, in the internal structure analysis system 100 for ceramics, the speckle noise removal processing unit 332 performs, in step S22 in the analysis process shown in the flowchart of FIG. As an example of the speckle noise removal processing performed on the OCT observation image shown in FIG. 13 (D), for example, the OCT observation image shown in FIG. 13 (C) is subjected to contrast averaging (horizontalization) processing. By using the original image shown in FIG. 13B obtained by trimming the extraction region as an input image a plurality of times and performing speckle noise removal processing according to the procedure shown in the flowchart of FIG. The target image as shown in (A) can be obtained.

  FIG. 14 shows an example of a structure inside the molded body different from the case of FIG. 11 and a processing procedure in the case of an optically inhomogeneous state, for example, when detecting a crack in the molded body.

  In the case where the machine learning unit 372 detects a crack in the compact, the processing procedure of FIG. 14 is determined by machine learning.

  The speckle noise removal processing unit 332 performs the processing in FIG. 14 according to the processing procedure determined by the machine learning unit 372.

  In the speckle noise elimination process shown in the flowchart of FIG. 14, [LAW] is a LargeArea process that sets a small area (less than the average area) to 255.

  [BDA] is a BinarizationDiscriminantAnalysis process for performing binarization based on a threshold calculated using a discriminant analysis method.

  [Me9] is a Mean9 process of outputting, for each pixel, an average value of pixels in a 9 × 9 window centered on the pixel of interest.

  [AlP] is AlgebraicProd (f1 × f2 / 255) processing.

  [LEX] is LinearExpand (255 × (f−15) / (255−15 ×) processing).

  [LTr] is LinearTransformation processing for extending the histogram.

  [LiP] is LightPixel processing for setting a pixel value smaller than a threshold value (average gradation value) to 0.

[Max] is a Maximum process of outputting, for each pixel, the maximum value of the pixels in a 3 × 3 window centered on the pixel of interest.
[LoS] is LogicalSum (max (f1, f2)) processing.

  [Ave] is Average ((f1 + f2) / 2) processing.

  [LT2] is LinearTransformation2 processing for extending the histogram while ignoring gradation values of less than 0.1% of the total number of pixels in the histogram.

  [Lap] is a Laplacian process for detecting edges with a Laplacian filter of a 3 × 3 window.

  [SqS] is SquareS ((γ = 0.5) pow (f / 255, 1 / γ) × 255) that slightly darkens the image.

  [Squ] is a Square ((γ = 0.9) pow (f / 255, 1 / γ) × 255) process for darkening an image.

  [000] is an input image, that is, an image before speckle noise removal.

  Further, in the internal structure analysis system 100 for ceramics, the speckle noise removal processing unit 332 performs, in step S22 in the analysis processing shown in the flowchart of FIG. As an example of the speckle noise removal processing performed on the OCT observation image shown in FIG. 15D, for example, the OCT observation image shown in FIG. 15C is subjected to contrast averaging (horizontalization) processing. By using the original image shown in FIG. 15B obtained by trimming the extraction region as an input image a plurality of times and performing speckle noise removal processing according to the procedure shown in the flowchart of FIG. The target image as shown in (A) can be obtained.

  In step S22 of the learning process shown in the flowchart of FIG. 9, the speckle noise removal processing unit 332 performs one of the speckle noise removal processes performed for each state of the molded body and for each type of the optically inhomogeneous state. The processing of FIG. 16 is performed.

  FIG. 16 illustrates an example of a processing procedure in which the speckle noise removal processing unit 332 detects an inhomogeneous region in a molded body, for example, as a processing procedure for performing the speckle noise removal processing.

  In the case where the machine learning unit 372 detects an inhomogeneous region in the compact, the processing procedure of FIG. 16 is determined by machine learning.

  The speckle noise removal processing unit 332 performs the processing in FIG. 16 according to the processing procedure determined by the machine learning unit 372.

  In the speckle noise removal processing shown in the flowchart of FIG. 16, [BDA] is a BinarizationDiscriminantAnalysis processing for performing binarization based on a threshold calculated using a discriminant analysis method.

  [Med] is Median processing for outputting, for each pixel, the median value of the pixels in a 9 × 9 window centered on the pixel of interest.

  [Gau] is a Gaussian filter for smoothing an image using a 3 × 3 window Gaussian filter.

  [BoP] is: BoundedProd ((f1 + f2-255)) processing.

  [BiM] is a BinarizationMean process for performing binarization using the average gradation value as a threshold value.

  [Me9] is a Mean9 process of outputting, for each pixel, an average value of pixels in a 9 × 9 window centered on the pixel of interest.

  [Clo] is Closing (maximum value filter → minimum value filter) processing.

  [ReC] is ReduceColor (f / 16 × 16 + 8) processing.

  [LAW] is a LargeArea process for setting a small area (less than the average area) to 255.

  [BDA] is a BinarizationDiscriminantAnalysis process for binarizing with a threshold calculated using a discriminant analysis method.

  [DaP] is DarkPixel processing for setting a pixel value equal to or larger than a threshold value (average gradation value) to 255.

  [Mea] is a Mean process for outputting, for each pixel, an average value of pixels in a 3 × 3 window centered on the pixel of interest.

  [Th] is a thinning method of Thinning Hilditch.

  [Max] is a Maximum process of outputting, for each pixel, the maximum value of a pixel in a 3 × 3 window centered on the pixel of interest.

  [VIn] is the dispersion image hmax.

  [Open] is an Opening (minimum value filter → maximum value filter) process.

  [LEX] is LinearExpand (255 × (f−15) / (255−15 ×)) processing.

  [DrP] is DrasticSun (f1 = 0 → f2, f2 = 0 → f1, f1, f2 ≠ 0 → 255) processing.

  [000] is an input image, that is, an image before speckle noise removal.

  In the ceramic internal structure analysis system 100A, the speckle noise removal processing unit 332 performs the removal processing of the speckle noise caused by the fine particles constituting the structure inside the molded body in the tomographic image, and the nonuniform state detection unit 333 performs the processing. In the tomographic image after the speckle noise removal processing, based on the shape and the size of the area where the luminance is different from the other, it is determined which of the structures inside the molded body has an optically inhomogeneous state. It is possible to detect a target heterogeneous state with high accuracy. Moreover, since the machine learning unit 372 determines the processing method in the speckle noise removal processing based on the machine learning for each state of the molded body, the speckle noise removal processing unit 332 performs processing according to the internal structure of the molded body. The method of the speckle noise removal processing can be selected, and the speckle noise removal processing can be performed with high accuracy.

  Since the machine learning unit 372 determines the processing method in the speckle noise removal processing based on the machine learning for each type of the optically inhomogeneous state, the speckle noise removal processing unit 332 determines the type of the optically inhomogeneous state. Speckle noise removal processing can be performed every time. This is expected to improve the accuracy of detecting the non-uniform state by the non-uniform state detection unit 333.

  The machine learning unit 372 performs machine learning based on learning data obtained by specifying the type of the optically inhomogeneous state by a method other than the method based on optical coherence tomography. Accordingly, it is expected that the classification of the learning data for each type of the optically inhomogeneous state can be performed with high accuracy.

  Since the learning data can be classified with high accuracy for each type of optically inhomogeneous state, it is expected that the learning accuracy of the method of removing speckle noise by the machine learning unit 372 will be improved.

  The above-described ceramic internal structure analysis systems 100 and 100A are provided with an optical coherence tomographic image obtained by in-situ observation of the molded body 1 being heat-treated by the heat treatment furnace 11 of the heat treatment apparatus 10 by the optical coherence tomographic image generation apparatus 20, By performing an analysis process of whether or not an optically inhomogeneous state has occurred in the image analysis processing device 30, it is possible to determine whether the sintered state of the compact 1 in the furnace is good or not, and to determine the optimum sintering conditions. Therefore, by changing the sintering conditions of the ceramics in the heat treatment furnace 11 of the heat treatment apparatus 10 based on the analysis result by the image analysis processing apparatus 30, the optimum sintering can be performed by the heat treatment furnace 11. For example, a ceramic manufacturing system 110 having a configuration as shown in the block diagram of FIG. 17 capable of sintering the compact 1 under the conditions can be constructed.

  FIG. 17 is a block diagram showing a configuration of a ceramic manufacturing system 110 to which the present invention is applied.

  The ceramic manufacturing system 110 shown in FIG. 17 performs the heat treatment of the ceramics in the heat treatment furnace 11 of the heat treatment apparatus 10 based on the analysis result by the image analysis processing apparatus 30 in the ceramic internal structure analysis system 100 shown in FIG. The condition is changed, and the analysis result by the image processing unit 31 of the image analysis processing device 30 is given to the information processing unit 16 of the control device 17 of the heat treatment device 10 via the data integration unit 32. ing.

  The components of the ceramic production system 110 are the same as those of the internal structure analysis system 100 for ceramics shown in FIG. 1, and therefore, the same components are denoted by the same reference numerals in FIG. Description is omitted.

  In the ceramic manufacturing system 110, the heat treatment apparatus 10 performs a heat treatment on the compact 1 formed by molding the ceramic raw material in a heat treatment furnace 11 composed of a high-temperature electric furnace.

The inorganic compound, which is a raw material of the ceramic, may be any substance that transmits light in the infrared region, and is not limited to a specific substance. Examples of such inorganic compounds, silicon oxide _(Si0 2), silicon nitride _{(Si 3 N} 4), hydroxyapatite _{(Calc (PO 4) 6 (} OH) 2), aluminum oxide _{(Al 2 0} 3), boron nitride (BN), yttrium oxide _{(Y 2 0} 3), zinc oxide (Zn0), titanium oxide _(Ti0 2), carbonate force calcium (CAC0 ₃₎ and barium titanate (BaTi0 _3), and the like.

  The heat treatment furnace 11 of the heat treatment apparatus 10 can control the temperature and time of the heat treatment on the compact 1 by the measurement / control unit 15 of the control device 17 using a CPU (Central Processing Unit). .

  In the ceramic manufacturing system 110, the analysis result by the image processing unit 31 of the image analysis processing device 30 is provided to the information processing unit 16 of the control device 17 of the heat treatment device 10 via the data integration unit 32, and the measurement / control unit Through the step 15, the temperature and time of the heat treatment on the compact 1 during the heat treatment in the heat treatment furnace 11 are controlled according to the above analysis results.

  That is, the ceramic production system 110 includes a heat treatment apparatus 10 for performing heat treatment on a molded body obtained by molding a ceramic raw material by a heat treatment furnace 11 and a molded body 1 which is being heat-treated in the heat treatment furnace 11. An optical coherence tomographic image generating device 20 for irradiating light in the infrared region from outside the heat treatment furnace 11 to perform optical coherence tomography and generate an optical coherent tomographic image, and an optical coherence tomographic image generated by the coherent tomographic image generating device 20 An image analysis processing device 30 for performing an image analysis process for determining whether an optically inhomogeneous state occurs in the internal structure of the formed body during the heat treatment process of the ceramics by using the image; The measurement and control unit 15 that changes the condition of the heat treatment of the ceramics in the heat treatment furnace 11 based on the analysis result by the device 30 Provided.

In the ceramic manufacturing system 110, the ceramic manufacturing process is performed by the heat treatment apparatus 10, the optical coherence tomographic image generation apparatus 20, and the image analysis processing apparatus 30 according to the procedure shown in the process diagram of FIG.
FIG. 18 is a process diagram showing a procedure of a method of manufacturing ceramics performed in the ceramics manufacturing system 110.

  That is, in the heat treatment step S <b> 1, a heat treatment is performed by the heat treatment furnace 11 on the molded body 1 formed by molding the ceramic raw material in the heat treatment apparatus 10.

  In the optical coherence tomographic image generation step S2, light in the infrared region is irradiated from the outside of the heat treatment furnace 11 by the optical coherence tomography image generation apparatus 20 to the molded body 1 being heat-treated in the heat treatment step S1 to perform optical coherence tomography. An optical coherence tomographic image is generated.

   In the analysis processing step S3, the image analysis processing apparatus 30 uses the optical coherence tomographic image generated in the optical coherence tomographic image generation step S2 to generate an optically inhomogeneous state in the internal structure of the compact during the heat treatment process of the ceramics. An analysis process is performed to determine whether any error has occurred.

  In the control step S4, the condition of the heat treatment of the ceramics by the heat treatment furnace 11 in the heat treatment step S1 is changed based on the analysis result in the analysis processing step S3.

  As described above, in the ceramics manufacturing system 110, by controlling the manufacture of the ceramics based on the analysis result by the image analysis processing device 30, it is possible to improve the accuracy of the ceramics manufacture, for example, to reduce the frequency of occurrence of pores and cracks. There is expected.

  The present invention is applied to, for example, a ceramic internal structure analysis system 200 having a configuration as shown in the block diagram of FIG.

  The ceramic internal structure analysis system 200 is different from the ceramic internal structure analysis system 200 shown in FIG. 1 in that a weighing device 50 including a weighing dish 51 on which the compact 1 is placed in the heat treatment furnace 11 is provided. Thus, it is possible to observe the structure inside the compact during the heat treatment process of the ceramics by the heat treatment furnace 11 and measure the weight change.

  Other components in the ceramic internal structure analysis system 200 are the same as the components of the ceramic internal structure analysis system 100 shown in FIG. 1, and therefore, the same components are denoted by the same reference numerals in FIG. , Its detailed description is omitted

  That is, the ceramic internal structure analysis system 200 includes a heat treatment apparatus 10 including a heat treatment furnace 11 for performing a heat treatment on a molded body 1 formed by molding a ceramic raw material, and a molded body being heat-treated in the heat treatment furnace 11. 1. An optical coherence tomographic image generating apparatus 20 for irradiating light in the infrared region from outside the heat treatment furnace 11 to generate optical coherent tomographic images by performing optical coherence tomographic imaging, and light generated by the coherent tomographic image generating apparatus 20 An image analysis processing device 30 that performs an image analysis process on an interference tomographic image, and a weighing device 50 that includes a weighing dish 51 on which the molded body 1 is placed in the heat treatment furnace 11 are provided.

  The weighing device 50 includes an electronic balance 53 having a movable column 52 displaceable together with a weighing dish 51 on which the molded body 1 is placed in the heat treatment furnace 11 and a weighing control device 56.

   The weighing control device 56 includes a CPU (Central Processing Unit) and includes a weighing / control unit 54 and a weighing information processing unit 55.

  In the internal structure analysis system 200 for ceramics, the electronic balance 53 of the weighing device 50 and the heat treatment furnace 11 of the heat treatment device 10 are placed on the base 41 of the stand 40 in a stacked state. The compact 1 is placed on a weighing dish 51 provided at the upper end of the movable column 52 of the electronic balance 53 inserted from the above.

  The electronic balance 53 measures the weight change of the mounted compact 1 via the movable column 52 movable in the vertical (Z) axis direction together with the weighing dish 51.

  In the ceramic internal structure analysis system 200, the weighing device 50 transmits the result of the weighing measurement by the electronic balance 53 whose operation is controlled by the weighing / control unit 54 of the weighing control device 56 to the weighing information processing unit 55 of the weighing control device 56. Output via.

  Therefore, in the ceramic internal structure analysis system 200, the weight change in the heat treatment process of the ceramics by the heat treatment furnace 11 is measured by the weighing device 50 including the weighing dish 51 on which the compact 1 is placed in the heat treatment furnace 11. can do.

  Further, in the ceramic internal structure analysis system 200, the heat treatment furnace on the base 41 is provided by the head holding portion 44 provided at the front end of the arm 43 extending laterally from the upper end of the column 42 of the stand 40. The optical axis of light in the infrared region irradiated onto the molded body 1 from the camera head unit 25 of the optical coherence tomographic image generation apparatus 20 whose holding posture is variably adjusted at a position above the molded body 1 is adjusted. The optical coherence tomographic image generating apparatus 20 can generate an optical coherence tomographic image with less noise in a state where the optical coherence tomographic image generating device 20 is tilted at a predetermined angle θ within an angle range of 1 to 10 ° with respect to the normal direction of the observation surface 1A. I can do it.

  In the ceramic internal structure analysis system 200, the internal structure of the ceramic is analyzed by the heat treatment apparatus 10, the optical coherence tomographic image generation apparatus 20, and the image analysis processing apparatus 30 according to the procedure shown in the process diagram of FIG. .

  FIG. 20 is a process chart showing a procedure of an internal structure analysis method performed in the ceramic internal structure analysis system 200.

  That is, in the heat treatment step S <b> 1, a heat treatment is performed by the heat treatment furnace 11 on the molded body 1 formed by molding the ceramic raw material in the heat treatment apparatus 10.

  In the optical coherence tomographic image generation step S2, light in the infrared region is irradiated from the outside of the heat treatment furnace 11 by the optical coherence tomography image generation apparatus 20 to the molded body 1 being heat-treated in the heat treatment step S1 to perform optical coherence tomography. An optical coherence tomographic image is generated.

   In the analysis processing step S3, the image analysis processing apparatus 30 uses the optical coherence tomographic image generated in the optical coherence tomographic image generation step S2 to generate an optically inhomogeneous state in the internal structure of the compact during the heat treatment process of the ceramics. An analysis process is performed to determine whether any error has occurred.

  Further, in the weight change measuring step S4, the weight change during the heat treatment of the ceramics by the heat treatment furnace 11 is measured by the weighing device 50.

  That is, in the ceramic internal structure analysis system 200, the image analysis processing device 30 applies the optical coherence tomographic image generated by the coherence tomographic image generation device 20 to the compact 1 being fired in the heat treatment furnace 11. In addition to performing the image analysis processing, the weight change during the heat treatment of the ceramics by the heat treatment furnace 11 can be measured by the weighing device 50.

  Here, the characteristics of the ceramics greatly depend on the internal structure, and the structure changes for each manufacturing process such as mixing, molding, degreasing, and firing. In particular, in the degreasing process, a large substance change such as melting, evaporation, thermal decomposition, and oxidation of the added organic substance occurs, and a volume change occurs, so that the molded article may be cracked or deformed.

  In the ceramic internal structure analysis system 200, the coherence tomographic image generation device 20 generates an optical coherence tomographic image and the weight change can be measured by the weighing device 50 for the compact 1 in the heat treatment furnace 11. In-situ observation of the degreasing process of ceramics and change of internal structure can be clarified.

  21A to 21E show optical coherence tomographic images of the molded body 1 obtained by in-situ observation of the degreasing process of the ceramics in the ceramic internal structure analysis system 200. FIG.

(A) to (E) of FIG. 21 show that 0.5 wt% of Y ₂ O ₃ powder (Shin-Etsu Chemical Co., Ltd.) was added to AlN powder (Tokuyama Co., H grade) as a raw material powder. RU-P) and wet mixed in ethanol. 10 wt% of paraffin as a binder (Junsei Chemical Co., mp. 46-48 ° C.) and 10 wt% of bis (2-ethylhexyl) phthalate as a lubricant (Fuji Film Wako Pure Chemical Co., Ltd.) ) And granulation, and then a molded body 1 is produced by uniaxial molding and CIP molding, and an infrared condensing heating electric furnace (IR-TP-1-2, Yonekura Seisakusho Co., Ltd.) is used as the heat treatment furnace 11. ), The molded body 1 is degreased at a maximum temperature of 600 ° C. and 1.0 mL / min in the air, and the state of the degreasing process is observed through the quartz glass window 14 above the heat treatment furnace 11 through the OCT (IVS-00-). WE, santec Co., Ltd., image analysis processing device with center wavelength 1300 nm, axial resolution 4.4 μm (refractive index n = 1), lateral resolution 9 μm, focal depth 0.3 mm, scan speed 20 kHz) It is an optical coherence tomographic image of the molded article 1 during degreasing obtained by performing in-situ observation using No. 30.

  The change in weight of the molded body 1 during degreasing was measured using an electronic balance (AP225WD, Shimadzu Corporation) 53.

  In FIG. 21, (A) is an optical coherence tomographic image obtained at 30 ° C., and the change in weight of the molded body 1 at this time was 0.0%.

  (B) is an optical coherence tomographic image obtained at 50 ° C., and the weight change of the molded body 1 at this time was 0.0%.

  (C) is an optical coherence tomographic image obtained at 158 ° C., and the weight change of the molded body 1 at this time was 0.3%.

  (D) is an optical coherence tomographic image obtained at 304 ° C., and the weight change of the molded body 1 at this time was 5.8%.

  (E) is an optical coherence tomographic image obtained at 600 ° C., and the weight change of the molded body 1 at this time was 9.6%.

  The molded body 1 has white and black regions, but in the optical coherence tomographic image, regions having different refractive indexes are detected as white, and regions where no light reflection occurs are detected as black.

  When the change in the optical coherence tomographic image during the degreasing was followed, it was observed that the internal structure changed substantially uniformly at around 50 ° C. This is considered to be because the temperature around the melting point of paraffin added as a binder was 50 ° C., and the paraffin was melted and AlN particles were rearranged.

  Subsequently, at around 158 ° C., it was observed that the white mass flowed in the air. It is considered that this is because paraffin was volatilized from the surface of the molded body, turned into an aerosol in the air, and flowed into the air in the heat treatment furnace 11. In addition, it was observed that the molded body moved during the heating, and that the internal structure changed continuously due to the appearance of regions having different contrasts between light and dark.

  As described above, in the ceramic internal structure analysis system 200, by observing the degreasing process of the ceramic molded body 1 using the interference tomographic image generation device 20, it is observed that the internal structure changes as the degreasing progresses, Internal observation changes can be clarified.

  The internal structure analysis system 200 for ceramics as described above uses the optical coherence tomographic image generation apparatus 20 to observe the molded article 1 being degreased in the heat treatment furnace 11 of the heat treatment apparatus 10 in-situ. The analysis processing device 30 performs an analysis process to determine whether an optically inhomogeneous state has occurred, and the weight change during the degreasing process of the ceramics by the heat treatment furnace 11 can be measured by the weighing device 50. Since the quality of the degreasing state of the molded body 1 can be determined and the optimal degreasing condition can be determined, the heat treatment furnace of the heat treatment apparatus 10 can be determined based on the analysis result by the image analysis processing apparatus 30. By changing the conditions for degreasing the ceramics in 11, the heat treatment furnace 11 can degreasing the compact 1 under the optimal degreasing conditions Example, if it is possible to build a ceramics manufacturing system 210 configured as shown in the block diagram of FIG. 22.

  FIG. 22 is a block diagram showing a configuration of a ceramic manufacturing system 210 to which the present invention is applied.

  This ceramic manufacturing system 210 is based on the analysis result by the image analysis processing device 30 and the observation result by the weighing device 50 in the ceramic internal structure analysis system 200 shown in FIG. The degreasing condition and the sintering condition of the ceramics are changed. The analysis result by the image processing unit 31 of the image analysis processing device 30 and the observation result by the weighing device 50 are transmitted to the heat treatment device 10 through the data integration unit 32. The information is provided to the information processing unit 16 of the control device 17.

  The components of the ceramic manufacturing system 210 are the same as the components of the ceramic internal structure analysis system 200 shown in FIG. 19, and therefore, the same components are denoted by the same reference numerals in FIG. Detailed description is omitted.

  In the ceramic manufacturing system 210, the heat treatment apparatus 10 performs a heat treatment such as a degreasing treatment or a sintering treatment on a molded body 1 formed by molding a ceramic raw material by a heat treatment furnace 11 composed of a high-temperature electric furnace.

  The heat treatment furnace 11 of the heat treatment apparatus 10 can control the temperature and time of the heat treatment on the compact 1 by the measurement / control unit 15 of the control device 17 using a CPU (Central Processing Unit). .

  In the ceramic manufacturing system 210, the analysis result by the image processing unit 31 of the image analysis processing device 30 and the observation result by the weighing device 50 are transmitted to the information processing unit 16 of the control device 17 of the heat treatment device 10 via the data integration unit 32. Given by the measurement / control unit 15, the temperature and time of the degreasing process and the sintering process on the compact 1 during the heat treatment such as the degreasing process and the sintering process in the heat treatment furnace 11 are analyzed by the image processing unit 31. And control according to the observation result by the weighing device 50.

  That is, the ceramics manufacturing system 210 includes a heat treatment apparatus 10 that performs heat treatment such as degreasing or sintering on a molded body 1 formed by molding a ceramic raw material by a heat treatment furnace 11, An optical coherence tomographic image is generated by irradiating light in the infrared region from outside the heat treatment furnace 11 to the compact 1 which is performing a heat treatment such as a degreasing process or a sintering process to generate an optical coherence tomographic image. Using the image generating device 20 and the optical coherence tomographic image generated by the coherent tomographic image generating device 20, whether an optically inhomogeneous state has occurred in the structure inside the compact during the degreasing process and the sintering process of the ceramics An image analysis processing device 30 for performing image analysis processing, and a weighing device for measuring a weight change in a degreasing process and a sintering process of the ceramics by the heat treatment furnace 11. 50, the heat treatment apparatus 10 measures and changes the degreasing condition and sintering condition of the ceramics in the heat treatment furnace 11 based on the analysis result by the image analysis processing device 30 and the observation result by the weighing device 50. The control unit 15 is provided.

  Then, in the ceramic manufacturing system 210, the ceramic manufacturing process is performed by the heat treatment apparatus 10, the optical coherence tomographic image generation apparatus 20, the image analysis processing apparatus 30, and the weighing apparatus 50 according to the procedure shown in the process diagram of FIG. You.

   FIG. 23 is a process diagram showing a procedure of a method for manufacturing ceramics performed in the ceramics manufacturing system 210.

  That is, in the heat treatment step S <b> 11, in the heat treatment apparatus 10, a heat treatment such as a degreasing treatment or a sintering treatment is performed by the heat treatment furnace 11 on the molded body 1 obtained by molding the ceramic raw material.

  In the optical coherence tomographic image generation step S12, the light in the infrared region from the outside of the heat treatment furnace 11 by the optical coherence tomography image generation apparatus 20 is applied to the molded body 1 that is performing the heat treatment such as the degreasing treatment and the sintering treatment in the heat treatment step S11. To perform optical coherence tomography to generate an optical coherence tomographic image.

In the analysis processing step S13, the image analysis processing apparatus 30 uses the optical coherence tomographic image generated in the optical coherence tomographic image generation step S12 to generate the inside of the molded body in a heat treatment process such as a degreasing process or a sintering process of ceramics. An analysis process is performed to determine whether the structure has an optically inhomogeneous state.
In the weight change measuring step S14, the weight change of the molded body 1 in the heat treatment process such as the degreasing process and the sintering process of the ceramic is measured by the weighing device 50.

  In the control step S15, the degreasing conditions and sintering conditions of the ceramics by the heat treatment furnace 11 in the heat treatment step S11 are changed based on the analysis results in the analysis processing step S13 and the observation results in the weight change measurement step S14. .

  As described above, in the ceramic manufacturing system 210, by controlling the manufacturing of the ceramic based on the analysis result by the image analysis processing device 30 and the observation result by the weighing device 50, for example, the frequency of occurrence of pores and cracks can be reduced. This can be reliably prevented, and the accuracy of ceramics production can be improved.

  Reference Signs List 1 molded body, 1A observation surface, 10 heat treatment apparatus, 11 heat treatment furnace, 13 sample table arm, 14 upper lid 14A window, 15 measurement / control unit, 16 information processing unit, 17 control device, 20 optical coherence tomographic image generation device, 21 Light source, 22 half mirror, 23 reference mirror, 24 detector, 25 camera head unit, 26 information processing unit, 27 optical coherence tomographic image generation unit, 30 image analysis processing device, 31 image processing unit, 32 data integration unit, 35 learning Apparatus, 41 base, 42 support, 40 stand, 25 camera head, 43 arm, 44 head holder, 51 weighing dish, 50 weighing device, 52 movable column, 53 electronic balance, 54 weighing / control unit, 55 weighing information Processing unit, 56 Weighing control device, 100 Internal structure analysis system for ceramics, 100A Internal structure solution for Lamix System, 110 ceramics manufacturing system, 200 ceramics internal structure analysis system, 210 ceramics manufacturing system, 310 first communication unit, 320 first storage unit, 330 first control unit, 331 analysis processing unit, 332 speckle noise removal Processing section, 333 non-uniform state detection section, 350 second communication section, 360 second storage section, 370 second control section, 361 learning data storage section, 371 learning data acquisition section, 372 machine learning section, S1 heat treatment step , S2 optical coherence tomographic image generation step, S3 analysis processing step, S4 weight change measurement step, S11 heat treatment step, S12 optical coherence tomographic image generation step, S13 analysis processing step, S14 weight change measurement step, S15 control step

Claims (13)

A heat treatment furnace for performing heat treatment on a molded body formed by molding a ceramic raw material;
An optical coherence tomographic image generation unit that generates an optical coherence tomographic image by performing optical coherence tomography by irradiating light in the infrared region from outside the heat treatment furnace to the molded body that is being heat-treated in the heat treatment furnace,
An internal structure observation apparatus for ceramics, wherein an internal structure of a formed body during a heat treatment process of the ceramics by the heat treatment furnace can be observed as an optical coherence tomographic image generated by the optical coherence tomographic image generation unit.   The optical coherence tomographic image generation unit inclines the optical axis of light in the infrared region irradiated on the molded body by a predetermined angle within a range of 1 to 10 ° with respect to a normal direction of an observation surface of the molded body. 2. The apparatus for observing the internal structure of ceramics according to claim 1, wherein: An attitude adjustment mechanism that varies a holding attitude of the optical coherence tomographic image generation unit,
By the attitude adjusting mechanism, the optical axis of the light in the infrared region irradiated on the molded body is inclined at a predetermined angle within the range of 1 to 10 ° with respect to the normal direction of the observation surface of the molded body. 3. The apparatus for observing an internal structure of a ceramic according to claim 2, wherein the apparatus holds an optical coherence tomographic image generation unit. An attitude adjusting mechanism that varies a holding attitude of the molded body in the heat treatment furnace,
The posture adjusting mechanism is in a state where the normal direction of the observation surface is inclined at a predetermined angle within the above-mentioned 1 to 10 ° angle range with respect to the optical axis of the light in the infrared region irradiated by the optical coherence tomographic image generation unit. The apparatus for observing the internal structure of a ceramic according to claim 1, wherein the apparatus holds the formed body. Further, a weighing device including a weighing dish on which the molded body is placed in the heat treatment furnace,
5. The apparatus for observing the internal structure of ceramics according to claim 3, wherein the change in weight can be measured together with the observation of the internal structure of the compact during the heat treatment of the ceramics by the heat treatment furnace. A heat treatment furnace for performing heat treatment on a molded body formed by molding a ceramic raw material;
An optical coherence tomographic image generating apparatus that generates an optical coherence tomographic image by performing light coherence tomography by irradiating light in an infrared region from outside the heat treatment furnace to the molded body that is being heat-treated in the heat treatment furnace,
An image analysis processing device that performs image analysis processing on the optical coherence tomographic image generated by the coherence tomographic image generation device,
Using the optical coherence tomographic image generated by the coherent tomographic image generation device, the image analysis processing device performs an image analysis process to determine whether an optically inhomogeneous state occurs in the structure inside the compact during the heat treatment process of the ceramics. An internal structure analysis system for ceramics.   The optical coherence tomographic image generating apparatus inclines the optical axis of light in the infrared region irradiated on the molded body by a predetermined angle within a range of 1 to 10 ° with respect to a normal direction of an observation surface of the molded body. The internal structure analysis system for ceramics according to claim 6, wherein: An attitude adjustment mechanism that varies a holding attitude of the optical coherence tomographic image generation apparatus,
The posture adjusting mechanism causes the optical axis of light in the infrared region irradiated on the molded body to be inclined at a predetermined angle within the angle range of 1 to 10 ° with respect to the normal direction of the observation surface of the molded body. 8. The ceramic internal structure analysis system according to claim 7, wherein the system holds an optical coherence tomographic image generation device. An attitude adjusting mechanism that varies a holding attitude of the molded body in the heat treatment furnace,
The attitude adjusting mechanism is configured to tilt the normal direction of the observation surface with respect to the optical axis of the light in the infrared region irradiated by the optical coherence tomographic image generation device at a predetermined angle within the above angle range of 1 to 10 °. The internal structure analysis system for ceramics according to claim 7, wherein the molded body is held. A weighing device including a weighing dish on which the molded body is placed in the heat treatment furnace,
The ceramic internal structure analysis system according to any one of claims 6 to 9, wherein a change in weight can be measured together with observation of a structure inside the compact during a heat treatment process of the ceramics by the heat treatment furnace. . A heat treatment step of heat-treating a molded body obtained by molding a ceramic raw material by a heat treatment furnace;
An optical coherence tomographic image generation step of generating an optical coherence tomographic image by performing optical coherence tomography by irradiating light in the infrared region from outside the heat treatment furnace to the molded body during the heat treatment in the heat treatment step,
A method for observing the internal structure of ceramics, wherein an internal structure of a formed body during a heat treatment process of ceramics can be observed as an optical coherence tomographic image generated in the optical coherence tomographic image generating step. A heat treatment step of heat-treating a molded body obtained by molding a ceramic raw material by a heat treatment furnace;
An optical coherence tomographic image generating step of generating an optical coherence tomographic image by irradiating light in an infrared region from outside the heat treatment furnace to the molded body during the heat treatment in the heat treatment step,
An image analysis processing step of performing image analysis processing on the optical coherence tomographic image generated in the optical coherence tomographic image generation step,
In the above-mentioned image analysis processing step, an internal structure analysis method for ceramics is performed, wherein an image analysis processing is performed to determine whether an optically inhomogeneous state occurs in a structure inside the molded body during the heat treatment process of the ceramics. A heat treatment step of heat-treating a molded body obtained by molding a ceramic raw material by a heat treatment furnace;
An optical coherence tomographic image generation step of generating an optical coherence tomographic image by irradiating light in an infrared region from outside the heat treatment furnace to the molded body during the heat treatment in the heat treatment step,
Using the optical coherence tomographic image generated in the optical coherence tomographic image generation step, an image analysis processing step of performing an image analysis processing as to whether or not an optically inhomogeneous state occurs in the structure inside the molded body in the heat treatment process of the ceramics; ,
Controlling the condition of heat treatment of the ceramics by the heat treatment furnace in the heat treatment step based on an image analysis result in the image analysis processing step.