Method and system for measuring high temperature viscosity of quartz glass

Abstract

The application belongs to the field of quartz glass, and particularly relates to a quartz glass high-temperature viscosity measurement method and a measurement system. The quartz glass high-temperature viscosity measurement method comprises the following steps: selecting quartz glass with less than 1 ppm of metal impurities and hydroxyl content as a standard sample, placing the quartz glass sample to be measured and the quartz glass standard sample in a crucible with a hole at the bottom respectively, heating to a measurement temperature, making the quartz glass sample flow out from the hole at the bottom of the crucible, and recording the deformation amount l of the quartz glass sample at the measurement temperature; calculating the viscosity of the quartz glass standard sample at the measurement temperature according to a quartz glass standard sample viscosity formula lgeta = (2.67*10 4 / T)-6.7; and calculating the viscosity of the quartz glass sample to be measured by using a linear proportional relationship of the deformation amount lgeta A *l A =lgeta B *l B . The application does not depend on a high-temperature viscometer commonly used in the detection industry, has higher temperature adaptability and simple operability, and is suitable for a high-temperature environment in an actual production process.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of quartz glass, and particularly relates to a quartz glass high-temperature viscosity measurement method and a measurement system. BACKGROUND

[0002] Quartz glass is made of pure natural quartz (such as crystal, quartz sand, etc.) or silicon compounds prepared by a chemical vapor deposition process. Quartz glass has a low thermal expansion coefficient, high temperature resistance, excellent chemical stability, excellent electrical insulation, optimal ultraviolet spectrum performance, and visible and near-infrared spectrum performance, and higher mechanical properties than ordinary glass. Therefore, it is an excellent material indispensable to space technology, atomic energy industry, national defense equipment, automation systems, and semiconductor, metallurgy, chemical industry, light industry, building materials, and other industries in modern cutting-edge technology.

[0003] Quartz glass, as an important basic raw material, is subjected to a high-temperature environment with a temperature of up to 1800℃ or above during melting and heat treatment in the production process. The glass can flow at such a high temperature. In order to evaluate the flowability, the viscosity of the glass needs to be measured. However, the high-temperature viscometer used in the detection industry can test a temperature of up to about 1700℃, which is still far from the actual heat treatment temperature. Therefore, a method for measuring the viscosity of quartz glass at high temperature needs to be developed. SUMMARY

[0004] In view of this, the purpose of the present application is to provide a quartz glass high-temperature viscosity measurement method and a measurement system. The method of the present application can test the viscosity of quartz glass at high temperature (above 1800℃), and can realize the relative comparison of the viscosity of various quartz glasses at high temperature.

[0005] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical solutions:

[0006] The present application provides a quartz glass high-temperature viscosity measurement method, comprising the following steps:

[0007] A flowing sample of quartz glass melt is provided; the quartz glass melt comprises a quartz glass standard sample A and a quartz glass sample to be measured B, the content of metal impurities and hydroxyl in the quartz glass standard sample A is less than 1 ppm; the temperature of the quartz glass melt is greater than 1730℃;

[0008] The temperature record deformation image of the quartz glass melt is kept, and the deformation amounts l A and l B of the flowing melt are obtained, respectively;

[0009] The linear proportional relationship lgη A *l Algη B * B , the viscosity of the quartz glass sample to be measured is calculated;

[0010] lgη in the linear proportional relationship of the deformation amount A According to the viscosity formula shown in formula I:

[0011] lgη T = (2.67 x 10 4 / T) - 6.7 formula I,

[0012] In formula I, the unit of temperature T is K.

[0013] Preferably, the shape of the quartz glass melt before melting is cylindrical, and the size is φ25mm*25mm.

[0014] Preferably, the quartz glass melt is obtained by melting quartz glass in a crucible, the bottom of the crucible is provided with a hole, and the flowing sample of the quartz glass melt flows out through the hole, and the material of the crucible includes one or more of graphite, tungsten and molybdenum.

[0015] Preferably, the hole is a circular hole, and the diameter of the circular hole is 5mm.

[0016] Preferably, the surface roughness Ra of the inner surface of the crucible is 0.1-0.4μm.

[0017] Preferably, the quartz glass melt is obtained by heating quartz glass, and the heating rate is 2-3℃ / min.

[0018] Preferably, the time for maintaining the temperature of the quartz glass melt is 0.5-4 hours.

[0019] Preferably, the temperature of the quartz glass melt is recorded during the deformation process, and the deformation amount of the flowing melt is obtained by using image processing software.

[0020] Preferably, the deformation amount of the flowing melt is obtained according to the position difference of the flowing sample of the quartz glass melt at the beginning and end of recording.

[0021] The application also provides a quartz glass high-temperature viscosity measurement system, which comprises a crucible with a hole at the bottom for containing a sample;

[0022] A high-temperature furnace with a light-transmitting observation port, wherein the crucible is placed in the high-temperature furnace;

[0023] A camera arranged outside the high-temperature furnace, used for recording the deformation of the quartz glass melt through the light-transmitting observation port.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention provides a method for measuring the high-temperature viscosity of quartz glass, comprising the following steps:

[0026] A flow sample of quartz glass melt is provided; the quartz glass melt includes quartz glass standard A and quartz glass test sample B, wherein the content of metallic impurities and hydroxyl groups in quartz glass standard A is less than 1 ppm; and the temperature of the quartz glass melt is greater than 1730℃.

[0027] By maintaining the temperature and deformation images of the molten quartz glass, the deformation l of the outflowing melt can be obtained. A and l B ;

[0028] Using the linear proportional relationship lgη of deformation variables A *l A =lgη B *l B The viscosity of the quartz glass sample was calculated.

[0029] lgη in the linear proportional relationship of deformation variables A According to the viscosity formula shown in Equation I:

[0030] lgη T = (2.67 × 10 4 / T)-6.7 Formula I,

[0031] In Equation I, the unit of temperature T is K.

[0032] The method for measuring the high-temperature viscosity of quartz glass in this invention does not rely on the high-temperature viscometers commonly used in the testing industry, has high temperature adaptability, and is suitable for high-temperature environments in actual production processes.

[0033] Furthermore, this invention uses a camera to record the deformation process of the quartz glass sample, and employs image processing technology to make the measurement process more intuitive and accurate, thereby improving the reliability of the measurement results. The method of this invention can accurately measure the viscosity of quartz glass at high temperatures (1730–1850°C), which helps to evaluate the performance of quartz glass, optimize the production process, and promote basic research.

[0034] The present invention also provides a system for measuring the high-temperature viscosity of quartz glass. The device has a simple structure, is easy to operate, and is easy to promote and apply. Attached Figure Description

[0035] In order to make the technical solutions in the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments will be briefly introduced. Obviously, the accompanying drawings in the following description only need to be some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0036] Figure 1 The device for measuring the high-temperature viscosity of quartz glass in the embodiments is shown in the schematic diagram, wherein 1 is a high-temperature resistant crucible, 2 is quartz glass, 3 is a crucible placing table, 4 is a high-temperature furnace, 5 is an observation port, and 6 is an industrial camera. DETAILED DESCRIPTION

[0037] The present application provides a method for measuring the high-temperature viscosity of quartz glass, comprising the following steps:

[0038] A flowing sample of a quartz glass melt is provided; the quartz glass melt comprises a quartz glass standard sample A and a quartz glass sample to be measured B, the content of metal impurities and hydroxyl groups in the quartz glass standard sample A is less than 1 ppm, and the temperature of the quartz glass melt is greater than 1730 ℃;

[0039] The temperature of the quartz glass melt is recorded to obtain a deformation image, and the deformation amount l A and l B of the flowing melt are obtained respectively;

[0040] The linear proportional relationship lgη A *l A =lgη B *l B of the deformation amount is used to calculate the viscosity of the quartz glass sample to be measured;

[0041] The linear proportional relationship lgη A According to the viscosity formula shown in formula I:

[0042] lgη T = (2.67 x 10 4 / T)-6.7 formula I,

[0043] In formula I, the unit of temperature T is K.

[0044] In the present application, the materials and equipment used are commercially available in the art unless otherwise specified.

[0045] The present application provides a flowing sample of a quartz glass melt; the quartz glass melt comprises a quartz glass standard sample A and a quartz glass sample to be measured B, the content of metal impurities and hydroxyl groups in the quartz glass standard sample A is less than 1 ppm, and the temperature of the quartz glass melt is greater than 1730 ℃.

[0046] In the present application, the temperature of the quartz glass melt (the temperature of the measurement of the high-temperature viscosity) is preferably 1800-1850°C, more preferably 1825°C.

[0047] In the present application, the metal impurities and the hydroxyl content in the quartz glass standard sample A are both less than 1 ppm, and the viscosity formula satisfies formula I:

[0048] lgη T = (2.67 x 10 4 / T) - 6.7 formula I,

[0049] In formula I, the unit of the temperature T is K;

[0050] For example, at temperatures of 1800°C, 1825°C and 1850°C respectively, according to formula I, the lgη of the quartz glass standard sample A (i.e. lgηA) is 6.17, 6.03 and 5.88 respectively, and the η of the quartz glass standard sample A (i.e. ηA) is 1.78 x 105Pa·s, 1.74 x 105Pa·s and 1.69 x 105Pa·s respectively. T T The unit of η is dPa·s.

[0051] In the present application, the shape of the quartz glass melt before melting is preferably cylindrical, and the size is preferably φ25mm*25mm. The shapes of the quartz glass standard sample A and the quartz glass sample to be measured B before melting are preferably consistent, so as to eliminate the influence of gravity and prevent the influence of different shapes on the deformation.

[0052] In the present application, the container for containing the quartz glass melt is preferably a crucible, and the material of the crucible is preferably one or more of graphite, tungsten and molybdenum; the material of the crucible in the present application is high-temperature resistant.

[0053] In the present application, the crucible preferably has a hole in the center of the bottom, and the hole is preferably a circular hole, and the diameter of the circular hole is preferably 5mm. The crucible is preferably polished before use, and the surface roughness Ra of the inner surface of the crucible after polishing, which is in contact with the quartz glass sample, is preferably 0.1-0.4μm. The inner surface of the crucible in the present application is smooth, which can reduce the friction, make the quartz glass deform smoothly, prevent the influence of the roughness on the deformation, and further affect the viscosity value measured.

[0054] In the present application, the flowing sample of the quartz glass melt is preferably formed by the flow of the quartz glass melt under the action of gravity, specifically, the quartz glass melt is placed in a crucible with a hole in the bottom, and the melt flows out of the hole under the action of gravity.

[0055] In the present application, the quartz glass melt is preferably obtained by melting quartz glass in a crucible, and the crucible has a hole in the bottom, and the flowing sample of the quartz glass melt flows out of the hole.

[0056] ​In the present application, the heating rate from room temperature to the measuring temperature is preferably 2-3℃ / min, more preferably 2.5℃ / min. The heating is preferably carried out in a high-temperature furnace which is preferably provided with a light-transmitting window (observation port) for facilitating the recording of the quartz glass melt deformation process using a video camera.

[0057] The present application records the temperature deformation image of the quartz glass melt, and obtains the deformation amount l of the flowed-out melt A and l B .

[0058] In the present application, the time for keeping the temperature (measuring temperature) of the quartz glass melt is preferably 0.5-4 hours, more preferably 1-2 hours. During the keeping of the measuring temperature, the quartz glass sample has a ready viscous flow, and the quartz glass sample flows out from the central hole at the bottom of the crucible under the action of gravity, forming a cylindrical deformation.

[0059] In the present application, the recording of the deformation image and the obtaining of the deformation amount of the flowed-out melt preferably include: recording the deformation process of the quartz glass sample using a video camera, and obtaining the deformation amount (deformation distance l) of the quartz glass sample using image processing software; more preferably, the deformation amount of the flowed-out melt is obtained according to the position difference of the flowing sample of the quartz glass melt at the beginning and end of recording (the image recorded by the video is used in cooperation with the temperature record, for example, when the temperature reaches 1800℃, the position of the quartz glass outflow end face is recorded once, and the position of the quartz glass outflow end face is recorded again after half an hour of constant temperature, and the deformation amount of the quartz glass at 1800℃ for half an hour is obtained by subtracting the two positions).

[0060] In the present application, the main technical parameters of the video camera preferably include: pixel size: 2.2μm*2.2μm; resolution @ frame rate: 2592*1944 maximum @ 24FPS; sensitivity: 18.8ke- / lux*sec.

[0061] The deformation amount l A and l B is obtained, and then the present application calculates the viscosity of the quartz glass sample to be measured using the linear proportional relationship lgη A *l A of the deformation amount. B *l B

[0062] The lgη A in the linear proportional relationship of the deformation amount is obtained according to the viscosity formula shown in formula I:

[0063] lgη T =(2.67×10 4 / T)-6.7 formula I, ​

[0064] In formula I, the unit of temperature T is K.

[0065] In the present application, the metal impurities and hydroxyl content in quartz glass standard sample A are less than 1 ppm, and the viscosity satisfies formula I, and the temperature T is substituted into the calculation to obtain lgη A .

[0066] The present application also provides a quartz glass high-temperature viscosity measurement system, comprising a bottom-holed crucible for containing a sample;

[0067] A high-temperature furnace with a light-transmitting observation port, wherein the crucible is placed in the high-temperature furnace;

[0068] A camera arranged outside the high-temperature furnace and configured to record the deformation of the quartz glass melt through the light-transmitting observation port.

[0069] In the present application, the camera records the deformation process of the quartz glass in the high-temperature furnace through the light-transmitting window (light-transmitting observation port), and the camera is arranged outside the high-temperature furnace. The high-temperature furnace is used to heat the quartz glass sample, and the crucible is used to contain the quartz glass sample.

[0070] In the present application, the main technical parameters of the camera preferably include: pixel size: 2.2 μm*2.2 μm; resolution @ frame rate: 2592*1944 maximum @ 24FPS; sensitivity: 18.8 ke- / lux*sec.

[0071] In the present application, the hole of the bottom-holed crucible is preferably located at the center of the bottom of the crucible, and the hole is preferably a circular hole, and the diameter of the circular hole is preferably 5 mm. The surface roughness Ra of the inner surface of the crucible is preferably 0.1-0.4 μm.

[0072] In the present application, the measurement system preferably further comprises a crucible placement table.

[0073] The present application provides an efficient quartz glass high-temperature viscosity measurement method and measurement system for the quartz glass industry. The importance of measuring the high-temperature viscosity of quartz glass includes the following aspects:

[0074] 1) The present application measures the high-temperature viscosity of quartz glass, which can evaluate the physical properties of the material, including its high-temperature deformation resistance, thermal stability, etc. Especially for quartz glasses prepared by different processes and with different hydroxyl and metal impurity contents, this method is simple and convenient to test their relative viscosity. Without prior determination of the hydroxyl and metal impurity content in the quartz glass, the viscosity at high temperature can be obtained.

[0075] 2) The invention measures the high-temperature viscosity of quartz glass, which helps better understand and optimize the high-temperature heat treatment process of quartz glass. For example, understanding the regularity of viscosity change with temperature can guide the formulation of temperature control strategies in the production process.

[0076] 3) High-temperature viscosity is an important physical property of glassy materials. The invention measures the high-temperature viscosity of quartz glass, which helps better understand the physical properties and behavior of glassy materials and promote scientific research in related fields.

[0077] In order to further illustrate the invention, the measurement method and measurement system of the high-temperature viscosity of quartz glass provided by the invention are described in detail below in conjunction with the drawings and examples, but they cannot be understood as limiting the scope of protection of the invention.

[0078] Example 1

[0079] 1. The schematic diagram of the device for measuring the high-temperature viscosity of quartz glass is shown in Figure 1 , wherein 1 is a high-temperature resistant crucible, 2 is quartz glass, 3 is a crucible placement table, 4 is a high-temperature furnace, 5 is an observation port, and 6 is an industrial camera.

[0080] The high-temperature furnace is used to heat the quartz glass sample, and the observation port is a light-transmitting window; the industrial camera is used to record the deformation process of the quartz glass sample at high temperature, and is equipped with image processing software to analyze the deformation size (deformation amount) of the quartz glass; the main technical parameters of the industrial camera include:

[0081] 1) Pixel size: 2.2 μm * 2.2 μm;

[0082] 2) Resolution @ frame rate: 2592 * 1944 maximum @ 24 FPS

[0083] 3) Sensitivity: 18.8 ke- / lux*sec.

[0084] 2. The method for measuring the high-temperature viscosity of quartz glass comprises the following steps:

[0085] 1) Respectively place the quartz glass standard sample and the quartz glass sample to be measured in the graphite crucible (high-temperature resistant crucible) and place it in the high-temperature furnace, and raise the temperature to the temperature to be measured; the diameter of the circular hole at the bottom center of the graphite crucible is 5 mm, and the surface roughness Ra of the part of the inner surface of the crucible contacting the quartz glass is 0.4 μm.

[0086] The quartz glass standard sample used in this example is A, and the quartz glass samples to be measured are B and C, and the contents of hydroxyl and metal impurities are as follows:

[0087] A: Hydroxyl content less than 1 ppm, metal impurities less than 1 ppm;

[0088] B: hydroxyl content less than 10 ppm, metal impurities 25 ppm;

[0089] C: hydroxyl content greater than 1000 ppm, impurities less than 1 ppm.

[0090] 2) Constant temperature for 60 min at the temperature to be measured, the quartz glass flows out from the bottom center hole of the crucible under the action of gravity, forming a cylindrical deformation; record the deformation process using a camera; the camera is placed outside the high-temperature furnace and records the deformation process of the quartz glass in the furnace through the light transmission window.

[0091] 3) Analyze the deformation amount (deformation distance) of the quartz glass sample by image processing software.

[0092] 4) Calculate the viscosity of the quartz glass to be measured at high temperature according to the formula lgη A * A = lgη B * B = lgη C * C .

[0093] Wherein the viscosity calculation formula of quartz glass standard sample A is: lgη T = (2.67 x 10 4 / T) - 6.7 (temperature unit in the formula is K), the viscosity (η T ) of standard sample A at temperatures of 1800℃, 1825℃ and 1850℃ is 10 6.17 , 10 6.03 , 10 5.88 , respectively, i.e. lgη T (lgη A ) is 6.17, 6.03 and 5.88, respectively, and the unit of η T is dPa·s.

[0094] Three quartz glasses (sample numbers A, B and C) prepared by different processes are cylindrical, with a size of φ25mm*25mm. The quartz glass cylinder is placed in a graphite crucible (the diameter of the bottom circular hole is 5mm) and placed in a high-temperature furnace; start the high-temperature heating furnace, the temperature rising rate is 2.5℃ / min, and it takes about 12 hours to rise to the constant temperature. The experimental design scheme and results are shown in the following table:

[0095] Table 1 Experimental design scheme and results of Example 1

[0096]

[0097] According to lgη T in Table 1, the viscosity η T of the quartz glass to be measured at the measurement temperature can be calculated.The viscosity of quartz glass is mainly affected by metal impurities and hydroxyl content, and the higher the metal impurities and hydroxyl content, the easier the flow at high temperature, that is, the smaller the viscosity. The B sample does not have an empirical formula, and the empirical formula of the C sample is lgη=(3.73x10 4 / T)-12.5. The calculated lgη of the C sample at 1800, 1825, and 1850°C is 5.49, 5.30, and 5.07, respectively, and the deviation of the measured lgη in Table 1 is 5%, 1.6%, and 5%, respectively. It can be seen that the measurement method of the present application is accurate and reliable.

[0098] The quartz glass sample with metal impurities and hydroxyl content less than 1 ppm is selected as a standard sample, and the quartz glass sample to be measured and the quartz glass standard sample are respectively placed in a crucible with a hole at the bottom and heated to the measurement temperature. The quartz glass sample flows out from the hole at the bottom of the crucible, and the deformation amount l of the quartz glass sample is recorded while maintaining the measurement temperature. According to the viscosity formula lgη=(2.67x10 4 / T-6.7 of the quartz glass standard sample, the viscosity of the quartz glass standard sample at the measurement temperature is calculated; and the linear proportional relationship of the deformation amount is lgη A *l A =lgη B *l B , and the viscosity of the quartz glass to be measured is calculated. The present application does not need to measure the content of metal impurities and hydroxyl in the quartz glass in advance, and the viscosity at the measurement temperature can be obtained according to the measured deformation amount. The quartz glass without an empirical formula can also obtain its viscosity at high temperature by using the measurement method of the present application.

[0099] Although the above embodiment describes the present application in detail, it is only a part of the embodiments of the present application, not all the embodiments, and other embodiments can be obtained without creative labor on the basis of the embodiments of the present application, which are within the protection scope of the present application.

Claims

1. A method of measuring the high temperature viscosity of quartz glass, characterized by, The method comprises the following steps: providing a flowing sample of a quartz glass melt; the quartz glass melt comprises a quartz glass standard sample A and a quartz glass sample to be measured B, the metal impurity and hydroxyl content of the quartz glass standard sample A are both less than 1 ppm; the temperature of the quartz glass melt is greater than 1730 DEG C; the quartz glass melt is obtained by melting quartz glass in a crucible, the bottom of the crucible is provided with a hole, the flowing sample of the quartz glass melt flows out through the hole, the material of the crucible comprises one or more of graphite, tungsten and molybdenum; the hole is a circular hole, the diameter of the circular hole is 5 mm; the surface roughness Ra of the inner surface of the crucible is 0.4 μm; The temperature record deformation image of the quartz glass melt is kept, and the deformation amount l of the melt flowing out is obtained respectively A and l B ; the time for keeping the temperature of the quartz glass melt is 0.5-4 hours; Using the linear proportional relationship of the deformation variable lgη A * A = lgη B * B The viscosity of the quartz glass sample to be measured is calculated. lg η in linear proportion to the deformation variable A According to the viscosity formula shown in formula I: lgη A = (2.67 x 10 4 / T) - 6.7 Formula I, in formula I, the unit of temperature T is K; the measuring system used in the method for measuring the high-temperature viscosity of the quartz glass comprises a crucible with a hole at the bottom for containing the sample; a high-temperature furnace with a light-transmitting observation port, the crucible is placed in the high-temperature furnace; a camera arranged outside the high-temperature furnace for recording the deformation of the quartz glass melt through the light-transmitting observation port.

2. The measurement method according to claim 1, characterized in that, the shape of the quartz glass melt before melting is a cylinder with a size of φ25 mm*25 mm.

3. The measurement method according to claim 1, characterized in that, the quartz glass melt is obtained by heating, and the heating rate is 2-3 DEG C / min.

4. The measuring method according to claim 1 or 3, characterized in that, the temperature of the quartz glass melt is recorded, and the deformation image is obtained, and the deformation amount of the flowing melt is obtained by using an image processing software to record the deformation process of the flowing melt.

5. The measurement method according to claim 4, characterized in that, the deformation amount of the flowing melt is obtained according to the position difference of the flowing sample of the quartz glass melt at the beginning and end of recording.

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