Evaluation device thermostable properities in high-temperature environment using induction heating

Abstract

The present invention relates to a high-temperature environment heat resistance evaluation device capable of evaluating electromagnetic and heat resistance properties at high temperatures by simulating extreme environments of supersonic speed and ultra-high temperature, and capable of measuring changes in mechanical material properties, including electromagnetic properties according to temperature, through rapid heating and cooling of a specimen using induction heating.

Description

Technology Field

[0001] The present invention relates to a device for evaluating heat resistance characteristics in a high-temperature environment, and more specifically, to a device for evaluating heat resistance characteristics in a high-temperature environment that simulates extreme environments of supersonic speed and ultra-high temperature to evaluate heat resistance characteristics at high temperatures, and is capable of measuring changes in mechanical material properties, including electromagnetic properties according to temperature, through rapid heating and cooling of a specimen using induction heating. Background Technology

[0002] In the aerospace and missile fields, various stealth technologies are being applied to suppress detection by radar and other means, particularly for military purposes, including interference from external noise electromagnetic waves. Recently, there has been a continuous increase in demand for stealth technologies applied to high-temperature regions of several hundred to over 1,000°C, such as the nozzle area of ​​stealth fighters and unmanned aerial vehicles, or the tip of stealth hypersonic missiles.

[0003] Conventional representative electromagnetic wave absorbers are composite materials in which powder of a soft magnetic metal is dispersed into a rubber or plastic matrix, and materials such as chlorinated polyethylene rubber or acrylic rubber are used with atomized powder of a soft magnetic metal such as Sendust, Pharmaloy, and Fe-Cr-Al alloy.

[0004] However, since this type of electromagnetic wave absorbing sheet has limitations in heat resistance, research and development of heat-resistant sheet materials are continuously being carried out in response to the aforementioned demands; in this process, it is important to accurately evaluate the level of low detectability performance of the electromagnetic wave absorber under temperature and time conditions.

[0005] Conventionally, methods for evaluating the performance of electromagnetic wave absorbers typically involved irradiating high-frequency electromagnetic waves using a network analyzer, or connecting a coaxial tube or waveguide to the circuit of a device that measures reflected or incident electromagnetic waves and installing a specimen of the electromagnetic wave absorber to be tested inside.

[0006] These devices typically have a temperature range of 90 to 120°C for evaluation, making it practically impossible to perform evaluations in high-temperature environments of several hundred to 1000°C. In particular, when heating a specimen, there was a significant problem with the risk of damage to the analyzer as heat is transferred to the network analyzer through the connection cable. Prior art literature

[0007] Republic of Korea Published Patent No. 10-2010-0102358 (September 24, 2010) The problem to be solved

[0008] The present invention was created in response to the above-mentioned needs, and the objective of the present invention is to provide a high-temperature environment heat resistance evaluation device capable of evaluating the high-temperature electromagnetic and heat resistance properties of electromagnetic wave absorbing materials by simulating extreme environments of supersonic speed and ultra-high temperature, while using induction heating to rapidly heat and cool specimens in the range of hundreds to thousands of degrees and measuring changes in mechanical material properties, including electromagnetic properties, according to temperature. means of solving the problem

[0009] For the above purpose, the present invention may be characterized by comprising: a fixing part for fixing a specimen composed of a conductive material combined with an electromagnetic wave absorbing material; an induction coil formed to maintain equal spacing corresponding to the shape of the specimen and heating an adjacent specimen through electromagnetic induction by the application of an AC power source; an electromagnetic wave absorption layer inspection module for inspecting the surface of the coating of the specimen heated through the induction coil and comparing and analyzing it with the surface condition of the specimen before heating; and a coil support part that supports the induction coil, but is fixed in position or moved in position so as not to interfere with the induction coil during the operation of the electromagnetic wave absorption layer inspection module.

[0010] At this time, it is preferable to further include a spraying unit that sprays cooling gas to protect the electromagnetic wave absorption layer inspection module from the high temperature of the specimen.

[0011] In addition, the specimen may be formed in the shape of a conical missile tip or an airfoil, and the induction coil may be configured in a conical shape corresponding to the external shape of the specimen.

[0012] In addition, the specimen may be formed in the shape of a hollow tube-shaped missile tip or airfoil, and the induction coil may be configured to be inserted into the specimen.

[0013] In addition, the specimen may be formed in a plate shape, and the induction coil may be configured to be spaced at an equal distance from the surface of the specimen.

[0014] In addition, it is preferable that the electromagnetic wave absorption layer inspection module be configured to optically inspect the surface of the specimen coating layer and to check for changes in porosity and composition, as well as cracks, before and after heating. Effects of the invention

[0015] The present invention provides a high-temperature environment electromagnetic property evaluation device that enables accurate evaluation of the electromagnetic and mechanical material properties of special high-temperature heat-resistant materials and materials with radio wave absorption capabilities manufactured for application in ultra-high temperature environments, and can be used in the development of low-observable technologies and various defense and aerospace fields.

[0016] In particular, rapid heating and cooling of the specimen are achieved by utilizing induction heating instead of a torch, which can suppress carbon accumulation that occurs in high-temperature regions due to specimen heating and can reduce evaluation reliability; furthermore, through the cooling structure, expensive evaluation equipment can be effectively prevented from being damaged by the high heat generated from the specimen. Brief explanation of the drawing

[0017] FIG. 1 is a perspective view showing the application of an electromagnetic measurement module according to the present invention. FIG. 2 is a block diagram showing the control configuration of an evaluation device according to the present invention. FIG. 3 is a perspective view showing the application of an electromagnetic wave absorption layer inspection module according to the present invention. FIG. 4 is an operating state diagram showing the movement of an induction coil according to the present invention. FIG. 5 is a perspective view showing a structure with a heat-blocking structure according to the present invention applied. FIG. 6 is an example diagram showing various types of specimen shapes. FIG. 7 is a structural diagram showing a rectangular specimen and an induction coil shape. FIG. 8 is a structural diagram showing the shape of a curved specimen and an induction coil, FIG. 9 is a structural diagram showing the shape of a flat specimen and an induction coil, FIG. 10 is a structural diagram showing a specimen in the form of an attachment capable of external heating and an induction coil shape. FIG. 11 is a structural diagram showing a specimen in the shape of a pointed end capable of internal heating and an induction coil shape. FIG. 12 is an example diagram showing various specimen shapes with a gap between the electromagnetic wave absorbing material and the conductive material. FIG. 13 is a structural diagram showing a specimen in the form of an externally heating attachment with a gap between the electromagnetic wave absorbing material and the conductive material, and an induction coil shape. FIG. 14 is a structural diagram showing a rectangular specimen with a gap between the electromagnetic wave absorbing material and the conductive material, and an induction coil shape. FIG. 15 is a structural diagram showing a curved specimen and an induction coil shape with a gap between the electromagnetic wave absorbing material and the conductive material. FIG. 16 is a structural diagram showing a flat specimen and an induction coil shape with a gap between the electromagnetic wave absorbing material and the conductive material. FIG. 17 is a structural diagram showing a specimen in the shape of a pointed end capable of internal heating with a gap between an electromagnetic wave absorbing material and a conductive material, and an induction coil shape. Figure 18 is an explanatory diagram illustrating a method of fixing a specimen with a gap between an electromagnetic wave absorbing material and a conductive material. Specific details for implementing the invention

[0018] The configuration of the heat resistance evaluation device for high-temperature environments according to the present invention will be described in detail below with reference to the attached drawings.

[0019] FIG. 1 is a perspective view showing the application of an electromagnetic measurement module according to the present invention, and FIG. 2 is a block diagram showing the control configuration of an evaluation device according to the present invention. The present invention is a device capable of measuring the performance of an electromagnetic wave absorbing material in a high-temperature environment for low-observability technology, that is, changes in electromagnetic wave characteristics and physical properties. The main components for this include a fixed part (110) and an induction coil (120), as well as an electromagnetic measurement module (140) for measuring electromagnetic wave characteristics and an electromagnetic wave absorption layer inspection module (150) for measuring the mechanical material properties of the electromagnetic wave absorbing material, which are provided together or optionally.

[0020] Typically, such electromagnetic wave absorbing materials include hydrocarbon-based materials or non-conductive dielectric materials such as ceramics. Performance evaluation of changes in electromagnetic properties due to heating and cooling of the specimen is performed by applying the material to the surface of a specimen, which is basically a metal material identical or similar to the actual product application form, as well as conductive materials such as SUS and graphite.

[0021] The above fixing part (110) is configured to fix a specimen (S) in which an electromagnetic wave absorbing material is bonded to a conductive material, and fixes the specimen (S) to have a sufficient exposure area so that smooth electromagnetic wave performance evaluation and mechanical material property evaluation can be performed.

[0022] As the above specimen (S) is configured in the form of a metal plate with an electromagnetic wave absorbing material coated on one side, it firmly holds the edge portion so as not to shake or detach during movement and evaluation, and as the above specimen (S) is heated to a high temperature of several hundred to 1000°C for evaluation, the above fixing part (110) is configured with a heat-resistant material that does not get damaged or deformed at high temperatures.

[0023] In the present invention, as a preferred embodiment, the specimen (S) is firmly held by a "┗┛" shaped support (111) having a groove formed on the inside corresponding to the thickness of the specimen so as to hold the left and right sides and the lower edge of the specimen, while allowing installation and removal to be performed by sliding upward through the space formed.

[0024] In addition, as described below, the specimen may be configured in the form of a missile tip or airfoil, such as a cone or a hollow tube to which a substantial electromagnetic wave absorbing material is applied, and a support body (111) may be configured in a suitable shape to fix it.

[0025] The above induction coil (120) is configured to heat the conductive material of a specimen to a high temperature of several hundred to 1000°C through electromagnetic induction, is formed to maintain equal spacing corresponding to the shape of the specimen, and heats adjacent specimens through electromagnetic induction caused by the application of an AC power source.

[0026] That is, by utilizing electromagnetic induction, an induced current flows in a specimen (S) within the high-frequency magnetic field of the induction coil (120), and this induced current generates Joule heat due to losses caused by eddy currents flowing swirling within the specimen (S) and hysteresis losses, and unlike conventional heating methods, heating and measurement of electromagnetic waves in a high-temperature state are possible within minutes.

[0027] In addition, when heating with a torch as in the conventional method, carbon may accumulate on the surface of hydrocarbon-based electromagnetic wave absorbing materials, which can cause distortion of electromagnetic waves. Therefore, in the embodiment of the present invention, the specimen is heated by induction heating to prevent such carbon accumulation.

[0028] The above electromagnetic measurement module (140) is configured to irradiate electromagnetic waves onto a specimen heated through the induction coil (120), measure the reflected waves, and calculate the amount of electromagnetic wave attenuation, and is composed of at least one X-band antenna that irradiates electromagnetic waves onto a specimen fixed at an evaluation position (M).

[0029] The electromagnetic measurement module (140) above can be used to evaluate the low detectability performance of a specimen heated to a high temperature, and the electromagnetic characteristics of a high-temperature environment are evaluated by comparing and analyzing the amount of electromagnetic attenuation caused by the electromagnetic wave absorbing material coated on the specimen before and after heating.

[0030] In the present invention, electromagnetic characteristics can be evaluated by directly heating the specimen to a high temperature of several hundred to 1000°C and transmitting and receiving electromagnetic waves, but the low detectability performance in a high-temperature environment can also be analyzed by evaluating the state of the electromagnetic wave absorbing material on the surface of the specimen, that is, mechanical properties.

[0031] FIG. 3 is a perspective view showing the application of an electromagnetic wave absorption layer inspection module according to the present invention. The electromagnetic wave absorption layer inspection module (150) provided for this purpose is configured to inspect the surface of the coating of a specimen heated through the induction coil (120) and measure the damage state by comparing it with the surface condition of the specimen before heating. Specifically, it is configured to optically verify the surface of the specimen coating layer and to check for changes in porosity and composition and cracks before and after heating.

[0032] Various means can be applied for this purpose, including infrared cameras for surface verification of high-temperature specimens and optical microscopes. This allows for the determination of whether electromagnetic wave absorption performance can be maintained smoothly by using compositional curve methods that record irregularities along a straight line on the specimen surface, identifying changes in porosity and the presence or absence of cracks, and conducting comparative analysis with the pre-heating state.

[0033] By using the above electromagnetic wave absorption layer inspection module (150), the surface condition of a specimen fixed at an evaluation position (M) after heating can be precisely inspected to measure low detectability performance, and the electromagnetic properties of the specimen in a high-temperature environment are evaluated by comparing and analyzing the surface condition of the electromagnetic wave absorbing material coated on the specimen before and after heating. At this time, the heating process of the specimen can be precisely photographed and analyzed using a high-speed camera, etc., which is protected through a transparent window and can photograph the specimen being heated.

[0034] These electromagnetic measurement modules (140) and electromagnetic wave absorption layer inspection modules (150) may be optionally provided, have a structure that allows for detachable replacement, or be provided together to perform an evaluation of electromagnetic characteristics suitable for each characteristic.

[0035] At this time, the induction coil (120) may be heated only when it is in close proximity to the specimen (S), and since the shape of the specimen may interfere with the measurement of the electromagnetic measurement module (140) and the electromagnetic wave absorption layer inspection module (150), it is necessary to move the position after heating the specimen (S). To this end, the coil support part (121) provided basically supports the induction coil (120) and is configured to allow it to be moved from the standby position (W) to the evaluation position (M), and FIG. 4 is an operational state diagram showing the movement of the induction coil according to the present invention.

[0036] As previously mentioned, in the present invention, an induction coil (120) is used to heat the specimen to a high temperature of several hundred to 1000°C, and depending on the shape of the specimen, the induction coil (120) in a close state may interfere with the smooth measurement operation of the electromagnetic measurement module (140) and the electromagnetic wave absorption layer inspection module (150). The standby position (W) and the evaluation position (M) are virtual reference positions set in the device, and the standby position (W) is set so that the induction coil (120) is removed after heating the specimen (S) so as not to interfere with the measurement operation of the electromagnetic measurement module (140) and the electromagnetic wave absorption layer inspection module (150), and the evaluation position (M) is set so that the electromagnetic performance of the fixed specimen is evaluated and the specimen (S) is heated through the induction coil (120), and the induction coil (120) is configured to be movable between the standby position (W) and the evaluation position (M).

[0037] It can be implemented in various ways, and basically, the coil support part (121) can be configured in various forms so that the induction coil (120) can move between the waiting position (W) and the evaluation position (M) set at each end of a virtual straight path, and a rail (122) connecting the waiting position (W) and the evaluation position (M) can be configured, and the coil support part (121) supporting the induction coil (120) can form a movable body in a form that can move along the rail (122).

[0038] As high heat is released from the specimen at a maximum temperature of around 1000°C immediately after being heated through the induction coil (120), damage to the relatively expensive electromagnetic measurement module (140) and electromagnetic wave absorption layer inspection module (150) may occur, and as the high temperature may cause malfunction of the sensitive sensor and measurement error, a method to prevent this is required.

[0039] To this end, a spraying unit (160) may be further included to rapidly remove heat by spraying cooling gas to the evaluation position (M). Various cooling gases may be used, and preferably, effective cooling can be achieved by using nitrogen gas capable of forming ultra-low temperatures through liquid nitrogen vaporization. The spraying unit (160) may be configured to spray cooling gas toward the specimen side for evaluating electromagnetic characteristics due to rapid cooling of the specimen, including the side of the electromagnetic measurement module (140) and / or the electromagnetic wave absorption layer inspection module (150). To this end, a distribution pipe (161) with nozzles (162) formed at intervals along a set section, and a valve for opening and closing the distribution pipe (161) to form a nitrogen curtain may be configured.

[0040] FIG. 5 is a perspective view showing a structure with a heat-blocking structure according to the present invention, wherein a shielding part (130) capable of blocking heat emitted from the specimen may be installed between the specimen at the evaluation position (M) and the electromagnetic measurement module (140) and / or the electromagnetic wave absorption layer inspection module (150).

[0041] At this time, so as not to impede the evaluation of electromagnetic characteristics caused by the shielding part (130), the shielding part (130) may be configured to include a shielding plate (131) that blocks heat from the specimen at the evaluation location to protect the electromagnetic measurement module (140) and / or electromagnetic wave absorption layer inspection module (150) from heat, and to be removable so that the shielding plate (131) does not obstruct the specimen during the measurement operation of the electromagnetic measurement module (140) and / or electromagnetic wave absorption layer inspection module (150).

[0042] The shielding plate (131) may be composed of a curtain or plate-shaped structure made of insulating material and is basically positioned between the specimen at the evaluation location (M) and the electromagnetic measurement module (140) and / or electromagnetic wave absorption layer inspection module (150) to block heat from the specimen. At this time, the shielding plate (131) can be moved or, in the case of a curtain-shaped shielding plate (131), folded so that the shielding plate (131) does not cover the specimen during the measurement operation of the electromagnetic measurement module (140) and / or electromagnetic wave absorption layer inspection module (150). Typically, the measurement operation of the electromagnetic measurement module (140) and / or electromagnetic wave absorption layer inspection module (150) takes about 10 seconds, so damage to the electromagnetic measurement module (140) and / or electromagnetic wave absorption layer inspection module (150) caused by heat emitted from the specimen can be sufficiently prevented. In the attached drawings, as a preferred embodiment, the shielding part (130) is configured to have a guide part (133) in the form of a rail formed on the upper, lower, left, or right sides of the shielding plate (131) and a jig connected to the shielding plate (131), so that the shielding plate (131) can be moved along the guide part (133), thereby illustrating a method of moving the position of the shielding plate (131). In addition, the shielding part can be configured in various other ways to allow for temporary removal, attachment, and positional movement of the shielding plate (131).

[0043] With the above-described series of configurations, the induction coil (120), the electromagnetic measurement module (140) and / or the electromagnetic wave absorption layer inspection module (150), the shielding part (130), and the injection part (160) can be individually or collectively controlled through a separate control module (170).

[0044] FIG. 6 is an example diagram showing various types of specimen shapes, where 6(a) shows a cone-shaped specimen like a missile tip, 6(b) shows a flat plate-shaped specimen, 6(c) shows a curved-shaped specimen, and 6(d) shows a hollow tube-shaped specimen of a missile tip. As previously mentioned, the specimen (S) is formed by combining a non-conductive dielectric material (S1) and a conductive material (S2), and the non-conductive dielectric material (S1), such as ceramic, is heated through induction heating of the conductive material (S2), such as SUS or graphite. In the attached drawings, for easy identification, the electromagnetic wave absorbing material (S1) in a room temperature state is shown in orange, the electromagnetic wave absorbing material in a heated state is shown in red, the conductive material (S2), represented by graphite, is shown in blue, and the induction coil (120) is shown in green.

[0045] FIG. 7 is a structural diagram showing a rectangular specimen and an induction coil shape, and FIG. 8 is a structural diagram showing a curved specimen and an induction coil shape, showing a specimen (S) positioned inside the induction coil (120) and heating taking place as previously illustrated.

[0046] FIG. 9 is a structural diagram showing the shape of a flat specimen and an induction coil. As described in FIG. 7 and 8, a pancake-shaped induction coil can be configured and a specimen placed in the center to perform heating work. However, while this configuration may result in reduced heating efficiency and take a long time, as shown in FIG. 9, the induction coil (120) is configured to be at an equal distance from the surface of the specimen (S), thereby improving heating efficiency and shortening the heating time.

[0047] FIG. 10 is a structural diagram showing a specimen and an induction coil shape capable of external heating, wherein the specimen (S) is formed in the shape of a conical missile tip or airfoil, and the induction coil (120) is formed in a conical shape corresponding to the external shape of the specimen (S), thereby allowing the induction coil (120) and the specimen (S) to maintain equal spacing, thereby improving heating efficiency and shortening heating time.

[0048] FIG. 11 is a structural diagram showing a specimen in the shape of a tip capable of internal heating and an induction coil shape, wherein the specimen is formed in the shape of a hollow tube missile tip or airfoil, and the induction coil (120) is configured to be inserted into the specimen (S).

[0049] As explained through FIGS. 7 to 10, the present invention basically requires that when the heating operation is performed with the induction coil (120) adjacent to the outside of the specimen (S), the induction coil (120) be moved so as not to interfere during the operation of the electromagnetic measurement module (140) or the electromagnetic wave absorption layer inspection module (150), as previously mentioned. However, when the heating operation is performed with the induction coil (120) inserted inside the specimen (S) as in FIG. 11, the induction coil (120) is not interfered with during the operation of the electromagnetic measurement module (140) or the electromagnetic wave absorption layer inspection module (150), so the induction coil (120) can be fixed in position.

[0050] Figures 6 to 11 attached illustrate specimens in which an electromagnetic wave absorbing material is in direct contact with a conductive material, such as graphite or metal, through a process such as coating. In this case, electromagnetic wave characteristics or mechanical material properties of the electromagnetic wave absorbing material are measured while the electromagnetic wave absorbing material is combined with the conductive material, but it is possible to measure electromagnetic wave characteristics or mechanical material properties of the electromagnetic wave absorbing material after heating the specimen and removing only the electromagnetic wave absorbing material.

[0051] FIG. 12 is an example diagram showing various specimen shapes with a gap between an electromagnetic wave absorbing material and a conductive material, wherein 12(a) shows a cone-shaped specimen like a missile tip, 12(b) shows a flat plate-shaped specimen, 12(c) shows a curved surface-shaped specimen, and 12(d) shows a hollow tube-shaped specimen of a missile tip, and unlike FIG. 6, the specimen is formed in a shape where a non-conductive dielectric material and a conductive material are separated by a certain distance.

[0052] Similarly, adjacent non-conductive dielectric materials are heated through induction heating of conductive materials such as SUS and graphite. For easy identification, electromagnetic wave absorbing materials at room temperature are represented in orange, electromagnetic wave absorbing materials in a heated state in red, conductive materials represented by graphite in blue, and induction coils in green.

[0053] FIG. 13 is a structural diagram showing a specimen in the form of an externally heatable tip and an induction coil shape with a gap between an electromagnetic wave absorbing material and a conductive material, wherein the specimen (S) is formed in the shape of a conical missile tip or an airfoil, and a gap is formed between the graphite or conductive material and the non-conductive dielectric material and they are maintained in close proximity.

[0054] The induction coil (120) is configured in a conical shape corresponding to the external shape of the specimen (S), and the induction coil and the specimen are kept at an equal distance, and the graphite or conductive material is heated through induction heating, and the electromagnetic wave absorbing material separated from it is also heated through heat transfer.

[0055] When the target temperature is reached, the induction heating device is stopped and the induction coil is separated from the specimen, and the conductive material and the electromagnetic wave absorbing material are separated. Subsequently, electromagnetic wave characteristics or mechanical properties are measured for the non-conductive material separated from the conductive material while it is heated to a high temperature.

[0056] FIG. 14 is a structural diagram showing a rectangular specimen and an induction coil shape with a gap between an electromagnetic wave absorbing material and a conductive material, and FIG. 15 is a structural diagram showing a curved specimen and an induction coil shape with a gap between an electromagnetic wave absorbing material and a conductive material. As shown in the figure, a specimen (S) is positioned inside the induction coil with a gap formed between a graphite or conductive material and a non-conductive dielectric material, maintaining a close state, and heating is performed.

[0057] Likewise, graphite or a conductive material is heated through induction heating, and a separate electromagnetic wave absorbing material is also heated through heat transfer. When the target temperature is reached, the induction heating device is stopped, the induction coil is separated from the specimen, and the conductive material and the electromagnetic wave absorbing material are separated to measure electromagnetic wave characteristics or mechanical properties.

[0058] FIG. 16 is a structural diagram showing a flat specimen and an induction coil shape with a gap between an electromagnetic wave absorbing material and a conductive material. It is configured such that a pair of pancake-shaped induction coils are formed, and a specimen is positioned in the middle where a gap is formed between a graphite or conductive material and a non-conductive dielectric material and the coil is kept in close proximity.

[0059] Likewise, graphite or a conductive material is heated through induction heating, and a separate electromagnetic wave absorbing material is also heated through heat transfer. When the target temperature is reached, the induction heating device is stopped, the induction coil is separated from the specimen, and the conductive material and the electromagnetic wave absorbing material are separated to measure electromagnetic wave characteristics or mechanical properties.

[0060] FIG. 17 is a structural diagram showing a specimen in the shape of a tip capable of internal heating with a gap between an electromagnetic wave absorbing material and a conductive material, and an induction coil shape, wherein the specimen is formed in the shape of a hollow tube missile tip or airfoil with a gap formed between a graphite or conductive material and a non-conductive dielectric material and maintaining a close state, and the induction coil (120) is configured to be inserted into the specimen (S).

[0061] Likewise, graphite or a conductive material is heated through induction heating, and a separated electromagnetic wave absorbing material is also heated through heat transfer, and in this case, the induction coil can be fixed in position without the separation work described above.

[0062] FIG. 18 is an explanatory diagram illustrating a method of fixing a specimen with a gap between an electromagnetic wave absorbing material and a conductive material. It shows a configuration in which a non-conductive material (S1) is fixed by a fixing part (110) that fixes the non-conductive material (S1) and a fixing part (110') that fixes the conductive material (S2) are separated and a gap is formed between the conductive material (S2), represented by graphite.

[0063] Through this, heating can be performed by positioning the non-conductive material (S1) and the conductive material (S2) in adjacent states, that is, together between the induction coil (120), and after heating is finished, the induction coil (120) is removed and the fixing part (110') jig holding the conductive material (S2) is removed, and then the high-temperature environment electromagnetic and heat resistance characteristics evaluation can be performed.

[0064] The rights of the present invention are not limited to the embodiments described above but are defined by what is stated in the claims, and it is obvious that a person skilled in the art may make various modifications and adaptations within the scope of the rights described in the claims. Explanation of the symbols

[0065] 110: Fixed part 111: Support body 120: Induction coil 121: Coil support 130: Shielding section 131: Shielding plate 132: Jig 133: Guide section 140: Electromagnetic measurement module 150: Electromagnetic wave absorption layer inspection module 160: Spray section 161: Distribution pipe 162: Nozzle 170: Control Module M: Heating and evaluation position W: Standby position S: Specimen S1: Non-conductive material S2: Conductive material

Claims

Claim 1 As an evaluation device for heat resistance characteristics in a high-temperature environment of an electromagnetic wave absorbing material, the device comprises: a specimen (S) configured such that an electromagnetic wave absorbing material, which is a non-conductive dielectric material (S1), and a conductive material (S2) are separated at a certain distance from each other; a fixing part (110) for fixing the non-conductive dielectric material (S1) and a fixing part (110') for fixing the conductive material (S2); an induction coil (120) formed to maintain equal spacing corresponding to the shape of the specimen (S) and heating the non-conductive dielectric material (S1) through heat transfer by heating the adjacent conductive material (S2) through electromagnetic induction caused by the application of an AC power source; an electromagnetic wave absorbing layer inspection module (150) that optically checks the surface of the non-conductive dielectric material (S1) heated through the induction coil (120), inspects for changes in porosity and composition and cracks before and after heating, and compares and analyzes the surface condition of the specimen before heating; and a device that supports the induction coil (120) and A rail (122) formed with a movable body for moving the coil support (121), which is fixed in position or moved in position so as not to interfere with the induction coil (120) during operation of the electromagnetic wave absorption layer inspection module (150); a shielding plate (131) that blocks heat from the specimen to protect the electromagnetic wave absorption layer inspection module (150) from heat, and a shielding part (130) that removes the shielding plate (131) so as not to obstruct the specimen during the measurement operation of the electromagnetic wave absorption layer inspection module (150); and a spraying part (160) that protects the electromagnetic wave absorption layer inspection module (150) from the high temperature of the specimen by spraying cooling gas through a distribution pipe (161) with nozzles (162) formed at intervals along a set section and a valve that opens and closes the distribution pipe (161).A high-temperature environment heat resistance evaluation device characterized by being composed of, and after heating of the conductive material (S2) through the induction coil (120), separating the induction coil (120) and simultaneously removing the fixing part (110') that fixes the conductive material (S2), leaving only the non-conductive dielectric material (S1), and then performing an optical inspection through the electromagnetic wave absorption layer inspection module (150). Claim 2 A high-temperature environment heat resistance evaluation device according to claim 1, wherein the specimen (S) is formed in the shape of a conical missile tip or airfoil, and the induction coil (120) is configured in a conical shape corresponding to the external shape of the specimen. Claim 3 A high-temperature environment heat resistance evaluation device according to claim 1, wherein the specimen (S) is formed in the shape of a hollow tube-shaped missile tip or airfoil, and the induction coil (120) is configured to be inserted into the specimen. Claim 4 A high-temperature environment heat resistance evaluation device characterized in that, in claim 1, the specimen (S) is formed in a plate shape, and the induction coil (120) is configured to be at an equal distance from the surface of the specimen. Claim 5 delete

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