WO2012039198A1

WO2012039198A1 - Hot displacement measuring device, hot displacement measuring method, and electric resistance measuring device

Info

Publication number: WO2012039198A1
Application number: PCT/JP2011/067763
Authority: WO
Inventors: 吉本　修; 岡田　雅樹
Original assignee: 東洋炭素株式会社
Priority date: 2010-09-22
Filing date: 2011-08-03
Publication date: 2012-03-29

Abstract

In order to obtain a hot displacement measuring device, a hot displacement measuring method, and an electric resistance measuring device which are capable of measuring the hot displacement amount and/or the electric resistivity easily and accurately in a high-temperature range, an electric resistance measuring device is characterized by being provided with a measuring chamber (1) in which a sample (10) is placed, holding members (4, 5) for holding the sample (10) in the measuring chamber (1), a direct-current power source (14) for passing a direct current through the sample (10) held by the holding members (4, 5) to heat the sample, a temperature measuring means for measuring the temperature of a measurement portion of the sample (10), and an electric resistivity measuring means for measuring the electric resistivity of the sample (10), and by being configured such that a wall portion (1a) constituting the outer peripheral portion of the measuring chamber (1) is formed from a material through which heat rays due to radiation from the sample (10) are transmitted, and the heat rays from the sample (10) are applied directly to the wall portion (1a) of the measuring chamber (1), pass therethrough, and are emitted to the outside.

Description

Hot displacement measuring device, hot displacement measuring method, and electrical resistance measuring device

The present invention measures a hot displacement measuring apparatus and a hot displacement measuring method capable of measuring a hot displacement for obtaining a coefficient of thermal expansion and the like, and measures an electrical resistivity of a sample that can be heated by energization. The present invention relates to an electrical resistance measuring device.

Various methods such as a differential dilatometer method, a push rod dilatometer method, and a microscopic telescope method are known as methods for measuring the amount of hot displacement for obtaining the coefficient of thermal expansion.

In the differential type and push rod type thermal expansion measurement methods, there is a problem that there is a limit to the heat resistance of the constituent devices, and measurement in a high temperature range is not possible. Further, there is a problem that there is no highly accurate standard substance in the high temperature range, and high measurement accuracy cannot be obtained.

In the microscopic telescope methods described in Patent Documents 1 to 4, imaging is difficult due to light emitted by the sample itself in a high temperature range, and even if measurement is possible, high measurement accuracy cannot be obtained. In addition, there is a problem that a small sample cannot be measured because the cameras are arranged side by side to image both ends of the sample.

In the microscopic telescope method described in

Patent Documents

5 and 6, a laser is used. In the high temperature range (1500 ° C. or higher), the sample emits light, so that heat radiation beyond the measurement wavelength range may occur, resulting in a problem that the S / N ratio deteriorates and high measurement accuracy cannot be obtained.

In addition, in the microscopic telescope method described in Patent Documents 1 to 5, the sample is indirectly heated, so that a heat insulating material and a cooling facility are required. In Patent Document 6, the sample is heated by energization. However, heat radiation is generated from the sample, and the surrounding material is heated to a high temperature by the radiant heat. For this reason, a heat insulating material and cooling equipment are needed.

Patent Document 6 and Patent Document 7 disclose a thermal expansion coefficient measuring device for measuring a thermal expansion coefficient at a high temperature. In these thermal expansion coefficient measuring apparatuses, a structure is employed in which the periphery of the sample is covered with a heat insulating material or a reflector serving as a sample container. The temperature in the measurement part of the sample is measured optically through an optical window formed in such a heat insulating material or reflector. Further, when a thermocouple is used for temperature measurement, a hole is formed in a heat insulating material or the like, a thermocouple is inserted into the hole, and the tip of the thermocouple is placed in the measurement part of the sample. Such a structure was the same in a conventional electrical resistance measuring apparatus that measures electrical resistivity at high temperatures.

Therefore, when the periphery of the sample measurement part is covered with a heat insulating material or a reflecting plate as in the above prior art, it is necessary to form an optical window or a hole in the heat insulating material or the reflecting plate in order to measure the temperature or the like. There is a problem that the structure of the measuring apparatus becomes complicated.

In the measurement of electrical resistivity in a high temperature range, an inert gas such as argon is generally used as the atmosphere gas of the sample heated to a high temperature. However, as disclosed in Non-Patent Document 1, since an inert gas such as argon gas is ionized and discharge occurs in a high temperature range, it is difficult to accurately measure the electrical resistivity. was there.

JP 60-39540 A Japanese Patent Laid-Open No. 61-7452 JP 61-172041 A Japanese Patent Laid-Open No. 06-167468 JP 2004-333154 A JP 2009-128066 A Japanese Patent Application Laid-Open No. 8-128977

A first object of the present invention is to provide a hot displacement measuring device and a hot displacement measuring method capable of measuring a hot displacement amount easily and accurately in a high temperature range.

A second object of the present invention is to provide an electrical resistance measuring apparatus capable of accurately measuring electrical resistivity in a high temperature range with a simple structure.

<First aspect>
A hot displacement measuring apparatus according to a first aspect of the present invention includes a measurement chamber in which a sample is installed, a heating unit for heating the sample, a temperature measuring unit for measuring the temperature in the measurement unit of the sample, A projection lens for enlarging and projecting the measurement unit, and a pair of imaging means for imaging each of the images at both ends of the measurement unit of the sample magnified by the projection lens are provided.

According to the first aspect of the present invention, each of the images at both ends of the measurement part of the sample magnified by the projection lens is picked up by different image pickup means, and the difference in displacement (displacement amount) between the both ends between the predetermined temperatures. ), The amount of hot displacement can be obtained. For this reason, since there is no part which contacts a sample directly, the amount of hot displacement can be easily measured even in a high temperature range.

In addition, since the images at both ends of the measurement unit are enlarged and each of the images at both ends is captured by different imaging means, measurement can be performed even if the sample is small. That is, it is possible to measure not only the length direction of the sample but also a minute amount of displacement in the radial direction of the sample. In addition, since no laser or the like is used, the S / N ratio is not lowered due to light emission from the sample in a high temperature range, and measurement can be performed with high accuracy.

Moreover, since it can be measured by the projection lens and the imaging means, it can be measured with a simple structure.

In the first aspect of the present invention, it is preferable that the heating means is a direct current power source for passing a direct current through the sample. By directing a direct current from a direct current power source, the sample can be directly heated, and thus a facility such as a heater necessary for indirect heating is not necessary, and measurement can be performed with a simple structure. In addition, it is economical because it is not necessary to raise the temperature of the entire measurement chamber.

Also, unlike the heating method using a heater, the ambient temperature can be made relatively low. For this reason, a projection lens, an imaging means, etc. can be installed near a sample, and an apparatus structure can be made small.

In the first aspect of the present invention, the wall portion constituting the outer peripheral portion of the measurement chamber is formed of a material that transmits heat rays due to radiation from the sample, and the heat rays from the sample are directly applied to the wall portion of the measurement chamber. It is preferable to be configured to be irradiated and radiated to the outside. By forming the wall portion of the measurement chamber from a material that transmits heat rays, the temperature rise of the measurement chamber wall portion can be suppressed. For this reason, a heat insulating material and cooling equipment become unnecessary. By forming the wall of the measurement chamber from a material that transmits heat rays, for example, even if the temperature of the sample is increased to about 3000 ° C., the temperature around the sample in the measurement chamber can be suppressed to an increase to about 200 ° C. it can.

Moreover, since the temperature rise in the measurement chamber can be suppressed, it is possible to suppress the discharge of the ionized inert gas and the occurrence of discharge when an inert gas such as argon is used as the atmosphere gas in the measurement chamber. it can. For this reason, measurement with higher accuracy is possible without affecting imaging in a high temperature range.

In the first aspect of the present invention, it is preferable that the material of the wall portion of the measurement chamber has a light transmittance of 80% or more at a wavelength of 0.4 to 2.0 μm. That is, the light transmittance at each wavelength in the above range is preferably 80% or more. Heat rays due to radiation from the sample are generated in a wide wavelength range, and the intensity increases as the temperature increases. However, the strength is not strong in the low temperature region, and it is considered that the contribution to the temperature rise for the object irradiated with heat rays is not so great. Further, the intensity of the heat rays due to radiation becomes shorter as the temperature becomes higher, and becomes a peak at a wavelength of 2.0 μm or less particularly at 1500 ° C. or higher, and the influence of heating due to radiation cannot be ignored. Therefore, particularly when the temperature of the sample is 1500 ° C. or higher, the wall portion transmits more light in the wavelength region of 2.0 μm or less, thereby suppressing the temperature rise of the wall portion, and consequently, inside the measurement chamber. Temperature rise can also be suppressed.

In the first aspect of the present invention, the wall of the measurement chamber is not particularly limited, but preferred examples include quartz glass and alumina. Since these materials easily transmit the heat ray, the temperature does not increase, and the temperature in the wall of the measurement chamber and the temperature in the measurement chamber can be suppressed. In particular, quartz glass is preferably used. In particular, quartz glass is preferable because it is transparent and has high heat resistance, so that a heated sample can be directly observed. For this reason, it is not necessary to install a window etc. in the wall part of a measurement chamber, and it can measure a high temperature easily with a thermal radiation type thermometer. In addition, other physical characteristics that can be measured by observing the sample can be easily measured. In addition, quartz glass has a small coefficient of friction, and the holding member can easily move freely when the holding member is placed directly in the measurement chamber.

In the first aspect of the present invention, the image of the measurement part of the sample is enlarged by the projection lens, and both ends in the radial direction are picked up by the image pickup means. Therefore, the wall part of the measurement chamber needs to be transparent. is there. Since quartz glass is transparent and has high heat resistance, it is particularly preferable as a material for forming the wall of the measurement chamber in the present invention. Further, by using one projection lens, it is possible to easily measure the amount of hot displacement by enlarging even a minute sample (for example, the radial direction of the sample).

In the first aspect of the present invention, the distance between the outer peripheral wall of the measurement chamber and the sample is preferably 50 mm or more. Since the heat rays due to the radiation from the sample are further attenuated according to the reach distance, the longer the distance from the sample, the harder the irradiated object is heated. In the present invention, the wall portion of the outer peripheral portion of the measurement chamber is made of a material that is difficult to be heated by radiation heat rays, and the wall portion can be further prevented from being heated by separating the wall portion by 50 mm or more. Note that the wall portion of the outer peripheral portion of the measurement chamber is preferably cylindrical in terms of ease of taking a distance from the sample, and the diameter is preferably 100 mm or more. Further, in order to replace the measurement chamber with an inert gas, the volume is preferably not too large, and the diameter is preferably 200 mm or less.

In the first aspect of the present invention, an illumination device that irradiates light to both ends of the sample may be further provided. By providing such an illumination device, an image can be taken with sufficient contrast from a low temperature range to a high temperature range. Therefore, the position of the end portion in the sample can be detected more accurately. When imaging is possible due to self-emission of the sample in a high temperature range, the measurement can be performed by switching off the illumination device.

In the first aspect of the present invention, it is preferable that a diaphragm or a filter is further provided between the sample and the projection lens. The diaphragm and / or filter can adjust the amount of light and remove light having an unnecessary wavelength, so that the position of the end of the sample can be detected more accurately.

In addition, by providing it between the sample and the projection lens, one aperture or filter can be provided. When provided between the projection lens and the imaging means, it is necessary to provide a diaphragm and / or a filter for each of the pair of imaging means. Moreover, it becomes necessary to adjust each diaphragm and / or filter individually, which is complicated.

The method for measuring a hot displacement according to the first aspect of the present invention includes a step of installing a sample in a measurement chamber, an enlarged measurement unit of the sample installed in the measurement chamber, and projecting both ends in a radial direction in an image of the measurement unit. Heating the sample while imaging each of the parts, and increasing the temperature; and determining the hot displacement of the sample from the temperature difference in the temperature increase and the displacement at both ends due to the temperature increase. It is characterized by providing.

According to the hot displacement measuring method of the first aspect of the present invention, the amount of hot displacement can be measured easily and accurately at high temperatures.

<Second aspect>
According to a second aspect of the present invention, a DC current is passed through the measurement chamber in which the sample is installed, a holding member for holding the sample in the measurement chamber, and the sample held in the holding member, and heating An electrical resistance measuring device comprising: a direct current power source for measuring, a temperature measuring means for measuring a temperature in a measurement part of the sample; and an electrical resistivity measuring means for measuring the electrical resistivity of the sample. And the wall part constituting the outer peripheral part of the measurement chamber is formed of a material that transmits heat rays by radiation from the sample, and the heat ray from the sample is directly irradiated to the wall part of the measurement chamber. It is characterized by being radiated to the outside.

In the measurement of electrical resistivity in the high temperature range of a sample that can be heated by energization, conventionally, in order to prevent the diffusion of heat and raise the temperature of the sample, a heat insulating material is provided around the sample measurement part. In addition, a cooling facility or the like has been provided in order to prevent a temperature rise in the outer peripheral portion of the measurement chamber and to reduce the danger particularly when the measurement person touches the hand. However, the present inventors have formed the wall portion constituting the outer peripheral portion of the measurement chamber from a material that transmits heat rays due to radiation from the sample, so that the wall portion constituting the outer peripheral portion of the measurement chamber and the measurement chamber can be reduced. It has been found that the temperature rise can be suppressed, and the electrical resistivity in the high temperature range can be measured more accurately and accurately with a simple structure without requiring a heat insulating material or a cooling facility.

For example, even if the sample temperature is raised to 3000 ° C., according to the present invention, the temperature around the sample in the measurement chamber can be increased to about 200 ° C., for example. That is, conventionally, since the heat insulating material and the shielding material covering the periphery of the sample are materials that absorb the heat rays from the sample, the temperature rises as the sample is heated. Due to the temperature rise of the heat insulating material and the shielding material, the temperature around the sample also rises to a high temperature, and it is difficult to accurately measure the electrical resistivity at high temperature due to the influence of gas around the sample. Furthermore, since the temperature of the outer peripheral part of a measurement chamber becomes high, the cooling equipment was needed. The present inventors changed such a conventional idea, and configured so that the heat rays from the sample were directly irradiated to the wall portion constituting the outer peripheral portion of the measurement chamber, and further absorbed the heat rays into the wall portion. It has been found that by using a difficult material, temperature rise in the wall portion and the measurement chamber constituting the outer peripheral portion of the measurement chamber can be suppressed. In the second aspect of the present invention, the heat rays from the sample directly pass through the wall of the measurement chamber and are almost radiated to the outside. For this reason, since there is almost no member that absorbs the heat rays from the sample in the measurement chamber, the temperature in the outer circumference of the measurement chamber and the measurement chamber is not increased to a high temperature, with a simple structure and high accuracy, in the high temperature range. Electrical resistivity can be measured. Furthermore, since the wall part of the outer peripheral part of the measurement chamber is in contact with the external atmosphere, it also has an effect of releasing heat to the outside, and the temperature is hardly increased.

In addition, even when an inert gas such as argon is used as the atmospheric gas in the measurement chamber, the temperature around the sample heated by energization does not become too high, so that the inert gas is ionized and discharge occurs. Can be prevented. For this reason, the influence on the electrical resistivity measurement by discharge can be reduced, and a more accurate electrical resistivity can be measured.

In the second aspect of the present invention, the material of the wall of the measurement chamber is preferably the same material as the wall of the measurement chamber in the first aspect.

In the second aspect of the present invention, it is preferable that the holding member is held in the measurement chamber so as to be movable in the length direction of the sample installed in the measurement chamber. When a direct current is applied to the sample and heated, the sample expands thermally. By holding the holding member in the measurement chamber so that it can move in the length direction of the sample, even if the sample expands in the length direction due to the thermal expansion of the sample, the holding member moves accordingly. The strain load on the sample due to the thermal expansion of the sample can be reduced, and deformation of the sample can be prevented. That is, the holding member is not fixed in the measurement chamber, but is directly placed in the measurement chamber. Thereby, the holding member can be moved on the measurement chamber. The measurement chamber is preferably cylindrical, and the holding member is preferably semicircular and placed along the shape of the cylindrical measurement chamber. Thereby, stability of a holding member can be improved and a measurement can be made easy.

Also, in the second aspect of the present invention, it is preferable that a reflector for reflecting the heat rays from the sample is provided between the sample measurement unit and the holding member. By providing such a reflector, it is possible to reduce the temperature rise of the holding member due to the heat rays from the sample. Therefore, the temperature rise in the wall part of the outer peripheral part of the measurement chamber and the measurement chamber can be further suppressed. Moreover, deterioration of the holding member due to heat can be prevented.

In the second aspect of the present invention, the distance between the outer peripheral wall of the measurement chamber and the sample is preferably 50 mm or more, as in the first aspect. The wall portion of the outer peripheral portion of the measurement chamber is preferably cylindrical in view of ease of distance from the sample, and the diameter is preferably 100 mm or more. Further, in order to replace the measurement chamber with an inert gas, the volume is preferably not too large, and the diameter is preferably 200 mm or less.

The temperature measuring means used in the second aspect of the present invention includes a thermocouple that measures a low temperature region and a radiation thermometer that measures a high temperature region. In the low temperature range (room temperature to about 1300 ° C.), the temperature can be measured with a thermocouple, and in the high temperature range (about 900 ° C. or higher), the temperature can be measured with a radiation thermometer. Thereby, more accurate temperature can be measured from a low temperature range to a high temperature range.

As described above, the electrical resistance measurement apparatus according to the second aspect of the present invention can use an inert gas such as argon gas as the atmospheric gas in the measurement chamber. In this case, it is preferable to further include an inlet for introducing an inert gas into the measurement chamber, an outlet for discharging the gas from the measurement chamber, and an exhaust means for exhausting the gas from the outlet.

The atmospheric gas in the measurement chamber in the second aspect of the present invention is not limited to an inert gas, but the use of an inert gas as the atmospheric gas prevents the sample from being denatured due to oxidation or the like. Can do. When an inert gas is used, as described above, the inert gas may be ionized at a high temperature range, thereby impairing the accuracy of electrical resistance measurement. According to the second aspect of the present invention, as described above, since the temperature rise in the measurement chamber can be suppressed, ionization of the inert gas can be suppressed. Accordingly, it is possible to reduce the adverse effect on the measurement of electric resistance due to the ionization of the inert gas, and it is possible to measure the electric resistivity more accurately.

In the second aspect of the present invention, a displacement amount measuring means for measuring the displacement amount of the edge in the radial direction of the measurement portion of the sample may be further provided. By using such a displacement amount measuring means, the coefficient of thermal expansion of the sample can be measured.

The displacement measuring means is preferably an optical measuring means. As described above, the wall of the measurement chamber is made of a transparent material, and the displacement of the edge of the sample measurement section in the radial direction can be easily measured by the optical measurement means provided outside the measurement chamber. can do.

According to the first aspect of the present invention, the amount of hot displacement can be measured easily and accurately in a high temperature range.

According to the second aspect of the present invention, the electrical resistivity in the high temperature range can be accurately measured with a simple structure.

FIG. 1 is a schematic diagram showing a hot displacement measuring device or an electric resistance measuring device according to an embodiment of the present invention. FIG. 2 is a perspective view showing a measurement chamber of the hot displacement measuring device or the electrical resistance measuring device of one embodiment according to the present invention. FIG. 3 is a perspective view showing a measuring unit of the hot displacement measuring device or the electric resistance measuring device shown in FIG. FIG. 4 is a plan view showing a measuring section of the hot displacement measuring device or the electric resistance measuring device shown in FIG. FIG. 5 is a sectional view taken along line AA shown in FIG. FIG. 6 is a plan view showing a holding member used in the hot displacement measuring device or the electrical resistance measuring device shown in FIG. FIG. 7 is a cross-sectional view taken along line AA shown in FIG. FIG. 8 is a plan view showing a presser plate used in the hot displacement measuring device or the electric resistance measuring device shown in FIG. FIG. 9 is a cross-sectional view taken along line AA shown in FIG. FIG. 10 is a plan view showing a sample to be measured by the hot displacement measuring device or the electric resistance measuring device shown in FIG. FIG. 11 is a side view of the sample shown in FIG. FIG. 12 is a side view showing a reflector used in the hot displacement measuring device or the electrical resistance measuring device shown in FIG. FIG. 13 is a plan view showing the reflector shown in FIG. FIG. 14 is a side view showing a metal plate used for manufacturing the reflector shown in FIGS. 12 and 13. FIG. 15 is a diagram schematically showing a hot displacement measuring device or an electric resistance measuring device according to an embodiment of the present invention. FIG. 16 is a perspective view illustrating a measurement unit of the electrical resistance measurement apparatus. FIG. 17 is a diagram showing the relationship between the measurement temperature and the resistance change rate in one sample measured using the electrical resistance measurement apparatus according to one embodiment of the present invention. FIG. 18 is a diagram showing the relationship between the measurement temperature and the resistance change rate in another sample measured using the electrical resistance measurement device according to one embodiment of the present invention. FIG. 19 is a diagram showing the relationship between the temperature and resistance of a sample measured by a conventional measuring apparatus.

Hereinafter, the present invention will be described with reference to specific embodiments, but the present invention is not limited to the following embodiments.

<First aspect>
FIG. 1 is a schematic diagram showing a hot displacement measuring apparatus according to an embodiment of the first aspect of the present invention.

The sample 10 is installed in a measurement chamber described later. In FIG. 1, the measurement chamber is not shown. An optical filter (or diaphragm) 21 and a projection lens 22 are provided outside the measurement chamber. The projection lens 22 is for enlarging and projecting both end portions 10 a and 10 b in the measurement unit of the sample 10. An optical filter (or diaphragm) 21 is provided between the sample 10 and the projection lens 22. The optical filter 21 adjusts the amount of light, removes light with an unnecessary wavelength, etc., and passes through the optical filter 21. Light enters the projection lens 22. The image of the measurement part of the sample 10 is incident on one projection lens 22 and then projected onto one-

dimensional CCDs

23 and 24 as a pair of imaging means. The one-dimensional CCD 24 images one end portion 10a of the sample 10. Further, the other end portion 10 b of the sample 10 is imaged on the one-dimensional CCD 23. In the present invention, the projection lens 22 images one end portion 10a in the radial direction in the image of the enlarged measurement portion of the sample 10 with the one-dimensional CCD 24 and the other end portion 10b with the one-dimensional CCD 23. Therefore, by appropriately adjusting the positions of the one-dimensional CCD 23 and the one-dimensional CCD 24, it is possible to correspond to the measurement of the sample 10 having various sizes.

The position of the other end 10b of the sample 10 can be detected by the inflection point 25a in the electric signal 25 from the one-dimensional CCD 23. Similarly, the position of the one end portion 10a of the sample 10 can be detected by the inflection point 26a of the electric signal 26 from the one-dimensional CCD 24. Thereby, the displacement amount with respect to the sample of the predetermined | prescribed temperature of the one end part 10a and the other end part 10b can be measured, and the distance from the one end part 10a of the sample 10 to the other end part 10b can be measured.

When the sample 10 is heated and thermally expanded, the sample 10 also expands in the radial direction, so that the distance between the one end 10a and the other end 10b changes. Thereby, the amount of hot displacement of the sample at a predetermined temperature difference can be obtained, and the coefficient of thermal expansion can be calculated.

FIG. 2 is a perspective view showing a measurement chamber of the hot displacement measuring apparatus according to one embodiment of the first aspect of the present invention. As shown in FIG. 2, the measurement chamber 1 is configured by arranging O-rings between both ends of a wall portion 1a made of a quartz glass tube, and a cap 2 and a cap 3 and fixing them with clips. . In the present embodiment, the cap 2 and the cap 3 are made of bakelite, but are not particularly limited as long as they have heat resistance, and may be metal or resin. A pipe serving as an inlet 18 for introducing an inert gas into the measurement chamber 1 is inserted into the cap 2. An inert gas is introduced into the measurement chamber 1 through the introduction port 18. In this embodiment, argon (Ar) is used as the inert gas. As the inert gas, other inert gases such as neon (Ne) and krypton (Kr) may be used. Further, nitrogen gas can be used instead of the inert gas.

Further, an exhaust port 19 is formed in the cap 3 provided on the opposite side. The exhaust port 19 is formed to exhaust the gas in the measurement chamber 1. Note that the exhaust port 19 is not shown in FIG. An exhaust pump (not shown) as exhaust means for exhausting the gas in the measurement chamber 1 is connected to the exhaust port 19.

After exhausting the gas in the measurement chamber 1 from the exhaust port 19, the atmosphere in the measurement chamber 1 can be changed to an argon gas atmosphere by introducing argon gas from the introduction port 18.

The sample 10 whose electrical resistivity is measured by the hot displacement measuring device of this embodiment is installed in the measurement chamber 1 by being held by the holding

members

4 and 5 in the measurement chamber 1.

As shown in FIG. 2, an electric wire 8 is connected to the holding member 4, and the electric wire 8 passes between the cap 2 and the wall portion 1a and is led to the outside. Similarly, an electric wire 9 is connected to the holding member 5, and the electric wire 9 is led to the outside through between the cap 3 and the wall portion 1 a. The

electric wires

8 and 9 are connected to a DC power source (not shown). By holding the sample 10 between the holding member 4 connected to the electric wire 8 and the holding member 5 connected to the electric wire 9, the sample 10 is supplied with a direct current from a DC power source, and the sample 10 is heated. Is done.

The quartz glass tube constituting the wall portion 1a is supported on a table 33 by

support members

31 and 32. In the present embodiment, a quartz glass tube having a diameter of 120 mm is used, and the transmittance of the quartz glass having a wavelength of 0.4 to 2.0 μm is 80% or more.

FIG. 3 is an enlarged perspective view showing the measurement unit of the hot displacement measuring apparatus shown in FIG.

As shown in FIG. 3, the holding member 4 is configured by combining a pedestal portion 4a and a pressing plate 4e. Similarly, the holding member 5 is also configured by combining a pedestal portion 5a and a pressing plate 5e. The pedestals 4a and 5a are made of graphite in the present embodiment. The holding plates 4e and 5e are made of copper in this embodiment.

4 is a plan view showing a measuring section of the hot displacement measuring apparatus shown in FIG. 2, and FIG. 5 is a cross-sectional view taken along line AA shown in FIG.

FIG. 6 is a plan view showing the pedestal 5a, and FIG. 7 is a cross-sectional view taken along the line AA in FIG. FIG. 8 is a plan view showing the pressing plate 5e, and FIG. 9 is a cross-sectional view taken along the line AA shown in FIG.

The pedestal portion 4a has the same structure as the pedestal portion 5a, and the presser plate 4e has the same structure as the presser plate 5e.

As shown in FIGS. 3 and 4, one end portion of the sample 10 is disposed in a groove 5i (see FIGS. 6 and 7) formed in the pedestal portion 5a, and a holding plate 5e is disposed thereon. Then, the bolt of the fixing tool 5b composed of a bolt and a nut is passed through the hole 5f of the pedestal portion 5a and the hole 5j of the holding plate 5e, and tightened with the nut, so that the pedestal portion 5a and the holding plate 5e are sandwiched and fixed. Yes.

Similarly, the other end portion of the sample 10 is sandwiched and fixed between the pedestal portion 4a and the pressing plate 4e by fixing the pedestal portion 4a and the pressing plate 4e with the fixture 4b.

FIG. 5 shows a state in which the sample 10 is sandwiched and fixed between the pedestal 5a and the holding plate 5e.

As shown in FIG. 5, the bottom surface of the pedestal portion 5 a has a semicircular shape along the inner surface of the wall portion 1 a, and the pedestal portion 5 a is arranged by being inserted into the cylindrical wall portion 1 a, It is not fixed to the part 1a. Similarly, the pedestal part 4a is inserted into the wall part 1a and is not fixed to the wall part 1a. Accordingly, the holding

members

4 and 5 are held in the measurement chamber 1 so as to be movable in the length direction of the sample 10 in the measurement chamber 1.

As shown in FIGS. 3 and 4, a reflector 6 is provided between the measurement member of the sample 10, that is, the portion of the sample 10 positioned between the holding member 4 and the holding member 5 and the holding member 4. Yes. Similarly, a reflector 7 is provided between the measurement unit of the sample 10 and the holding member 5. The distance between the reflector 6 and the reflector 7 is not particularly limited, and may be changed according to the length of the sample 10. That is, the

reflectors

6 and 7 are fixed to the holding

members

4 and 5, and the distance is changed together with the holding

members

4 and 5 depending on the length of the sample 10.

FIG. 12 is a side view showing the reflector 6, and FIG. 13 is a plan view showing the reflector 6. The reflector 6 is manufactured by processing a metal plate made of stainless steel SUS304 having the shape shown in FIG. As shown in FIG. 14, a cutout portion 6a through which the sample 10 is passed is formed, and cutouts 6d and 6e are formed on both sides thereof. The hatched portions outside the cuts 6d and 6e are extracted by punching. The flaps 6b and 6c shown in FIGS. 12 and 13 are formed by bending the notches 6d and 6e at the base portions thereof. The flap portions 6b and 6c are formed with notches for allowing the attachment screws 4c to pass therethrough. The reflector 7 has the same shape as the reflector 6.

As shown in FIG. 4, the attachment screw 4c is passed through the flap portion of the reflector 6, and the reflector 6 is attached to the pedestal portion 4a. Similarly, the reflector 7 is attached to the pedestal 5a by passing the attachment screw 5c through the flap of the reflector 7. As shown in FIGS. 5, 6, and 7, the attachment screw 5 c is attached by being screwed into a hole 5 g formed in the pedestal portion 5 a.

Since the

reflectors

6 and 7 are made of stainless steel as described above, the heat rays radiated from the sample 10 can be reflected. The reflector 6 is provided between the measurement unit of the sample 10 and the holding member 4, and the reflector 7 is provided between the measurement unit of the sample 10 and the holding member 5. Therefore, at the time of measurement, the heat rays radiated from the sample 10 can be reflected so as not to be applied to the holding member 4 and the holding member 5. For this reason, it can suppress that the holding member 4 and the holding member 5 absorb a heat ray, and a temperature rise. For this reason, it can suppress that the temperature in the measurement chamber 1 rises. Further, the holding member 4 and the holding member 5 can be prevented from being deteriorated by the heat rays from the sample 10. The

reflectors

6 and 7 preferably reflect at least infrared rays.

A fixing tool 5d made of a bolt and a nut is attached to the hole 5h shown in FIG. 6, and the electric wire 9 is attached to the holding member 5 by the fixing tool 5d. Similarly, the fixture 4d is attached to a hole formed in the pedestal portion 4a, and the electric wire 8 is connected to the holding member 4 by the fixture 4d.

FIG. 15 is a diagram schematically showing the hot displacement measuring apparatus of the present embodiment.

As shown in FIG. 15, the sample 10 is disposed in the measurement chamber 1 in which the wall portion 1 a is made of quartz glass. The other end of each of the electric wire 8 and the electric wire 9 having one end connected to the DC power source 14 is connected to the sample 10. By applying a direct current to the sample 10, the sample 10 can be heated and the temperature of the sample 10 can be raised. An ammeter 15 is provided between the DC power supply 14 and the sample 10. As the DC power source 14, it is preferable to use a constant voltage constant current power source.

The temperature of the measurement part of the sample 10 is measured by the thermocouple 13 in the low temperature range. The thermocouple 13 is attached to the sample 10 with an adhesive. Therefore, in the present embodiment, the thermocouple 13 is disposable. Data measured by the thermocouple 13 is sent to a temperature measurement circuit / data logger 17. Further, the temperature of the measurement part of the sample 10 in the high temperature range is measured by a radiation type thermometer 16 provided outside the measurement chamber 1. The temperature data measured by the radiation type thermometer 16 is sent to a temperature measurement circuit / data logger 17. Based on the temperature data measured in this way, a signal is sent from the temperature measurement circuit / data logger 17 to the DC power source 14 to control the current or voltage to be applied to the sample 10 and to control the temperature increase rate of the sample 10. Can do. The displacement data measured by the optical displacement measuring device 20 is also sent to the temperature measurement circuit / data logger 17 to derive the displacement amount of the sample at each temperature with respect to the sample at a predetermined temperature.

An optical displacement measuring device 20 is provided outside the measurement chamber. The optical displacement measuring device 20 is the device described with reference to FIG.

As described above, in the present embodiment, the wall portion 1a of the measurement chamber 1 is formed of quartz glass. Quartz glass is a material that transmits heat rays and transmits heat rays generated from the sample 10. For this reason, the temperature rise in the measurement chamber 1 can be suppressed, and the amount of hot displacement in the high temperature region can be accurately measured with a simple structure without requiring a heat insulating material or a cooling facility.

When the temperature of the measurement part of the sample 10 was raised to about 3000 ° C. with the radiation thermometer 16, the temperature in the wall 1a above the sample 10 was measured and found to be 396 ° C. Moreover, it was 149 degreeC in the place about 100 mm away from the center of the measurement part of the sample 10, ie, above the

reflectors

6 and 7. FIG. Moreover, when the temperature in the end part of the measurement chamber 1, that is, in the vicinity of the

caps

2 and 3, is measured, it is about 100 ° C., and it can be seen that the temperature in the measurement chamber 1 is extremely low.

Therefore, in this embodiment, the temperature rise around the measurement unit of the measurement chamber 1 can be suppressed. Therefore, the heat insulating material and the cooling equipment, which are conventionally required, are no longer necessary.

Moreover, since the temperature rise of 1 of a measurement chamber can be suppressed, when inert gas, such as argon, is used as atmospheric gas in the measurement chamber 1, it suppresses that an inert gas ionizes and discharge arises. be able to. For this reason, more accurate measurement is possible without adversely affecting imaging in a high temperature range.

As described above, in the present embodiment, the both ends 10a and 10b in the image of the measurement unit of the sample 10 magnified by the projection lens 22 are imaged by the pair of

imaging units

23 and 24, and the both ends 10a and 10b The amount of hot displacement can be determined from the amount of displacement with respect to the sample having a predetermined temperature of 10b. For this reason, since there is no part which contacts the sample 10 directly, the amount of hot displacement can be easily measured even in a high temperature range.

Further, since no laser or the like is used, it is possible to measure with high accuracy without causing a decrease in the S / N ratio due to light emission from the sample in a high temperature range.

Moreover, since it can measure with the projection lens 22 and the imaging means 23 and 24, it can measure with a simple structure.
<Second aspect>
The measurement chamber of the electrical resistance measurement device of one embodiment according to the second aspect of the present invention is the same as the measurement chamber of the hot displacement measurement device according to the first aspect of the present invention shown in FIG. Since the measurement chamber 1 is as described with reference to FIGS. 3 to 14, its description is omitted.

FIG. 16 is a perspective view showing a state in which the voltage

drop detection terminals

11 and 12 are in contact with the measurement part of the sample 10. As shown in FIG. 16, the tips of the pair of voltage

drop detection terminals

11 and 12 are brought into contact with the measurement part of the sample 10. The voltage

drop detection terminals

11 and 12 are made of graphite. The voltage

drop detection terminals

11 and 12 are supported by support rods 11a and 12a made of stainless steel, respectively. The distance between the tips of the voltage

drop detection terminals

11 and 12 was set to 7 to 15 mm. However, the tip of the voltage

drop detection terminals

11 and 12 may be brought into contact with a location where the sample 10 is soaked, and is not limited to the above range.

A thermocouple 13 is attached to the lower surface of the measurement unit of the sample 10. The thermocouple 13 is attached to the sample 10 with an adhesive. Therefore, in the present embodiment, the thermocouple 13 is disposable.
The electrical resistance measuring device of this embodiment has the same structure as the hot displacement measuring device shown in FIG.

As shown in FIG. 15, the sample 10 is disposed in the measurement chamber 1 in which the wall portion 1 a is made of quartz glass. The other end of each of the electric wire 8 and the electric wire 9 having one end connected to the DC power source 14 is connected to the sample 10. By applying a direct current to the sample 10, the sample 10 can be heated and the temperature of the sample 10 can be raised. As the DC power source 14, a constant voltage constant current power source is preferably used.

The sample 10 is provided so that the voltage

drop detection terminals

11 and 12 are in contact with each other as described above. An ammeter 15 is provided between the DC power supply 14 and the sample 10. By measuring the voltage drop between the voltage

drop detection terminals

11 and 12 and measuring the current value with the ammeter 15, the electrical resistivity in the measurement part of the sample 10 can be obtained. The current value in the ammeter 15 and the value of the voltage drop at the voltage

drop detection terminals

11 and 12 are sent to the temperature measurement circuit / data logger 17 to calculate the electrical resistivity relative to the sample temperature.

The temperature of the measurement part of the sample 10 is measured by the thermocouple 13 in the low temperature range. Data measured by the thermocouple 13 is sent to a temperature measurement circuit / data logger 17. Further, the temperature of the measurement part of the sample 10 in the high temperature range is measured by a radiation type thermometer 16 provided outside the measurement chamber 1. The temperature data measured by the radiation type thermometer 16 is sent to a temperature measurement circuit / data logger 17. Based on the temperature data measured in this manner, a signal is sent from the temperature measurement circuit / data logger 17 to the DC power source 14 to control the amount of current or voltage to be supplied to the sample 10 and to control the rate of temperature increase of the sample 10. be able to.

Further, the optical displacement measuring device 20 described with reference to FIG. 1 is provided outside the measuring chamber 1. The optical displacement amount measuring device 20 is a device for measuring the displacement amount of both end edges in the radial direction of the measurement portion of the sample 10.

As described above, in the present embodiment, the wall portion 1a of the measurement chamber 1 is formed of quartz glass. Quartz glass is a material that transmits heat rays and transmits heat rays generated from the sample 10. For this reason, the temperature rise in the measurement chamber 1 can be suppressed, and the amount of hot displacement and electrical resistivity in the high temperature range can be accurately measured with a simple structure without requiring a heat insulating material or a cooling facility. .

17 and 18 are diagrams showing the relationship between the measurement temperature of the sample measured using the electrical resistance measurement apparatus of the present embodiment and the resistance change rate. Here, as the sample 10, isotropic graphite (manufactured by Toyo Tanso Co., Ltd., grade name “IG-12”: FIG. 17) and isotropic graphite (manufactured by Toyo Tanso Co., Ltd., grade name “TTK-50”: FIG. 18). ) Was used. As shown in FIGS. 17 and 18, the resistance change rate can be accurately measured up to a high temperature of about 2800 ° C.

FIG. 19 shows the measurement results of the isotropic graphite (grade name “IG-110”) shown in FIG. 2 on page 35 of Non-Patent Document 1, which is the prior art. As shown in FIG. 18, when the temperature is 2400K or higher, the resistance value starts to decrease. This is presumably because the argon gas in the vicinity of the sample is ionized, so that the current flows not only through the sample but also through the argon gas, and the apparent electrical resistance of the sample decreases.

On the other hand, in this embodiment, since the temperature rise in the measurement chamber 1 can be suppressed as described above, it is possible to suppress the argon gas, which is the atmospheric gas, from being ionized, and the electricity can be accurately generated. The resistivity can be measured.

In this embodiment, graphite is used as the sample 10, but the sample that can be measured by the apparatus of the present invention is not particularly limited as long as the sample can be heated by energization, such as ceramics and metal. Can also be measured.

DESCRIPTION OF SYMBOLS 1 ... Measurement chamber 1a ... Wall part 2 ... Cap 3 ... Cap 4 ... Holding member 4a ... Base part 4b ... Fixing tool 4c ... Mounting screw 4d ... Fixing tool 4e ... Plate 5 ... Holding member 5a ... Base part 5b ... Fixing part 5c ... Mounting screw 5d ... Fixing tool 5e ... Plate 5f ... Hole 5g ... Hole 5h ... Hole 5i ... Groove 5j ... Hole 6 ... Reflector 6a ... Cut out part 6b, 6c ... Flap part 6d, 6e ... Cut 7 ... Reflector 8 ... Electric wire DESCRIPTION OF SYMBOLS 9 ... Electric wire 10 ... Sample 10a ... One end part 10b ... The other end part 13 ... Thermocouple 14 ... DC power supply 15 ... Ammeter 16 ... Radiation type thermometer 17 ... Temperature measurement circuit and data logger 18 ... Inlet 19 ... Exhaust outlet 20 ... Optical displacement measuring device 21 ... Optical filter 22 ... Projection lens 23 ... One-dimensional CCD
24 ... one-dimensional CCD
25 ... Electric signal 25a ... Inflection point 26 ... Electric signal 26a ...

Inflection point

31, 32 ... Support member 33 ... Stand

Claims

A measurement room where the sample is installed;
Heating means for heating the sample;
Temperature measuring means for measuring the temperature in the measurement part of the sample;
A projection lens for enlarging and projecting the measurement part of the sample;
A hot displacement measuring device comprising: a pair of imaging means for capturing images of both ends of the measurement unit of the sample magnified by the projection lens.
2. The hot displacement measuring apparatus according to claim 1, wherein the heating means is a DC power source for supplying a DC current to the sample.
A wall portion constituting the outer peripheral portion of the measurement chamber is formed of a material that transmits heat rays due to radiation from the sample, and the heat rays from the sample are directly irradiated on the wall portion of the measurement chamber to be external. The hot displacement measuring device according to claim 1 or 2, wherein
4. The hot displacement measuring apparatus according to claim 3, wherein the material of the wall portion of the measuring chamber has a light transmittance of a wavelength of 0.4 to 2.0 μm of 80% or more.
The hot displacement measuring device according to claim 3 or 4, wherein the wall portion of the measuring chamber is made of quartz glass.
The hot displacement measuring apparatus according to any one of claims 3 to 5, wherein a distance between a wall portion of the measuring chamber and the sample is 50 mm or more.
The hot displacement measuring apparatus according to any one of claims 1 to 6, further comprising an illuminating device that irradiates light to both ends of the sample.
The hot displacement measuring apparatus according to any one of claims 1 to 7, further comprising a diaphragm and / or a filter between the sample and the projection lens.
Installing the sample in the measurement chamber;
A process of enlarging and projecting the measurement part of the sample installed in the measurement chamber, heating the sample and raising the temperature while imaging each of the images at both ends of the measurement part with a pair of imaging means When,
A hot displacement measuring method comprising: obtaining a hot displacement amount of the sample from a temperature difference in the temperature rise and a displacement amount of the both end portions due to the temperature rise.
A measurement room where the sample is installed;
A holding member for holding the sample in the measurement chamber;
A DC power supply for heating the sample held by the holding member by applying a direct current to the sample;
Temperature measuring means for measuring the temperature in the measurement part of the sample;
An electrical resistance measuring device comprising electrical resistivity measuring means for measuring the electrical resistivity of the sample,
The wall part which comprises the outer peripheral part of the said measurement chamber is formed from the material which permeate | transmits the heat ray by the radiation from the said sample, and the said heat ray from the said sample is directly irradiated to the said wall part of the said measurement chamber. An electrical resistance measuring device configured to be radiated to the outside.
The electrical resistance measurement apparatus according to claim 10, wherein the material of the wall portion of the measurement chamber has a light transmittance of 80% or more at a wavelength of 0.4 to 2.0 µm.
The electrical resistance measurement apparatus according to claim 10 or 11, wherein the holding member is held in the measurement chamber so as to be movable in a length direction of the sample installed in the measurement chamber.
The reflector according to any one of claims 10 to 12, wherein a reflector for reflecting the heat rays from the sample is provided between the measurement unit of the sample and the holding member. Electrical resistance measuring device.
The electrical resistance measurement apparatus according to any one of claims 10 to 13, wherein a distance between a wall portion of the measurement chamber and the sample is 50 mm or more.
The electrical resistance measuring device according to any one of claims 10 to 14, wherein the temperature measuring means is a thermocouple that measures a low temperature region and a radiation thermometer that measures a high temperature region.
An inlet for introducing an inert gas into the measurement chamber;
An outlet for exhausting gas from the measurement chamber;
The electrical resistance measurement apparatus according to any one of claims 10 to 15, further comprising exhaust means for exhausting gas from the exhaust port.
The electrical resistance measurement apparatus according to any one of claims 10 to 16, wherein the wall portion of the measurement chamber is made of quartz glass.
The electrical resistance measurement apparatus according to any one of claims 10 to 17, further comprising a displacement amount measuring means for measuring a displacement amount of an edge in a radial direction of the measurement portion of the sample.
The electrical resistance measuring device according to claim 18, wherein the displacement measuring means is an optical measuring means.