Ceramic glue discharging and sintering integrated process and ceramic high-temperature deformation and thermal weight loss synchronous analysis method

Abstract

The invention provides a ceramic glue discharging and sintering integrated process and a ceramic high-temperature deformation and thermal weight loss synchronous analysis method, and the process provided by the invention has the following advantages: 1) through integration of glue discharging and sintering processes, the production efficiency is improved; 2) the production cost is reduced; 3) thermal behaviors of the ceramic sample in different stages can be better understood through accurate quality and size change data monitoring, so that the process control is optimized, and the ceramic quality is improved; and (4) large-size sample application is supported: the system breaks through the limitation of traditional differential thermal analysis (DTA) in large-size sample testing, so that the glue discharging and sintering processes of large-size ceramic samples can be accurately controlled, and the requirements on large samples in industrial production are met.

Description

Technical Field

[0001] The invention belongs to the technical field of ceramic material sintering, and in particular relates to a ceramic debinding and sintering integrated process and a ceramic high-temperature deformation and thermal weight loss synchronous analysis method. Background Art

[0002] Debinding is the process of removing organic binders from ceramic raw materials by heating, which is usually completed before 600°C. Sintering is the process of combining ceramic particles and finally forming them by high temperature heating (greater than 1200°C). During the ceramic debinding stage, the organic binder gradually decomposes and volatilizes, resulting in a gradual decrease in the quality of the ceramic sample, accompanied by a slight volume change. During the sintering stage, the ceramic particles form a dense structure through diffusion and bonding, resulting in a large change in the volume of the ceramic sample. Therefore, accurate mass change and size change data are crucial to understanding and optimizing the heating process.

[0003] In the traditional ceramic production process, debinding and sintering are usually carried out as two independent processes. This separate process flow leads to problems such as complex process control, high energy consumption, and low efficiency. In the prior art, it is difficult to achieve precise control and coordinated optimization of the debinding and sintering processes, resulting in unstable product quality, especially in the production of high-precision and high-performance ceramics. Therefore, the development of an integrated optimization process for ceramic debinding and sintering is not only an effective way to improve the quality and production efficiency of ceramic products, but also a necessary means to reduce costs, environmentally friendly production and meet high performance requirements. Summary of the invention

[0004] The purpose of the present invention is to provide an integrated process for debinding and sintering of ceramics and a method for simultaneous analysis of high-temperature deformation and thermal weight loss of ceramics. The process and method of the present invention can simultaneously measure the mass change and dimensional change of ceramic samples during the heating process, so as to solve the problem in the prior art that the debinding and sintering processes are difficult to coordinately optimize, and improve the quality and production efficiency of ceramic products.

[0005] The present invention provides a ceramic debinding and sintering integrated process, using a ceramic debinding and sintering integrated system to heat a ceramic sample;

[0006] The ceramic debinding and sintering integrated system includes a high-temperature furnace module, a quality measurement module, a size measurement module, and a data acquisition and processing module;

[0007] The high-temperature furnace module comprises a heating furnace, and the heating furnace comprises a partition component, and the partition component divides the heating furnace into two sealed spaces, the first furnace cavity located at the upper part of the heating furnace, and the second furnace cavity located at the lower part of the heating furnace; a heating device is arranged outside the first furnace cavity;

[0008] The mass measurement module includes a high-temperature electronic balance and a ceramic sample support device, the high-temperature electronic balance is placed in the second furnace cavity, and the ceramic sample support device includes a base and a frame; the base is located in the first furnace cavity and is used to place ceramic materials; the frame passes through the partition component, one end of which is connected to the base, and the other end is connected to the high-temperature electronic balance;

[0009] The heat preservation temperature of the heating treatment is 1500-1600° C., and the heating rate of the heating treatment is 1-15° C. / min.

[0010] Preferably, the base is a corundum gasket, and the frame is a corundum frame.

[0011] Preferably, the size measuring module comprises an optical measuring device, and the optical measuring device comprises a light source and a high-speed camera.

[0012] Preferably, the outer wall of the first furnace cavity is provided with a transparent window, and an optical measuring device is arranged outside the transparent window.

[0013] Preferably, a heating device is used to heat the first furnace cavity to perform a heat treatment on the ceramic material;

[0014] The temperature in the second furnace chamber is lower than 200°C.

[0015] Preferably, the heat preservation time of the heating treatment is 1 to 5 hours.

[0016] The present invention provides a method for synchronously analyzing high temperature deformation and thermal weight loss of ceramics, comprising the following steps:

[0017] A) The ceramic sample is heated according to the ceramic debinding and sintering integrated process described above;

[0018] B) using the mass measurement module to collect the mass change data of the ceramic sample in real time, and the size measurement module to collect the size change data in real time;

[0019] C) Use the data acquisition and processing module to analyze the mass change data and size change data.

[0020] Preferably, in the step B), a size measurement module is used to collect images of the sample in real time during the heating process, and size change data is obtained through an image recognition algorithm.

[0021] Preferably, a temperature-mass change curve and a temperature-size change curve are drawn based on the real-time collected mass change data and size change data of the ceramic sample.

[0022] Preferably, the mass change data obtained in step B) is calibrated and then used for data analysis in step C);

[0023] The calibration includes: heating the ceramic debinding and sintering integrated system without placing a ceramic sample according to the ceramic debinding and sintering integrated process described above; the mass measurement module collects mass change data of the high-temperature electronic balance in real time to obtain calibration data;

[0024] The calibration data at the same temperature is subtracted from the ceramic sample mass change data to obtain the calibrated ceramic sample mass change data.

[0025] The present invention provides a ceramic debinding and sintering integrated process and a ceramic high-temperature deformation and thermal weight loss synchronous analysis method. The beneficial effects of the process of the present invention are mainly reflected in the following aspects:

[0026] 1. Improve production efficiency: By integrating debinding with sintering process, the production process is simplified, the production cycle is shortened, and production efficiency is significantly improved. The system can simultaneously monitor deformation and thermal weight loss data, optimize process parameters in real time, and reduce unnecessary steps and equipment in traditional processes.

[0027] 2. Reduce production costs: The integrated process design reduces equipment requirements and labor costs, while avoiding the switching between debinding and sintering processes, reducing energy consumption and waste of production resources.

[0028] 3. Improve ceramic quality: Through precise monitoring of mass and dimensional change data, we can better understand the thermal behavior of ceramic samples at different stages, thereby optimizing process control and ensuring that the final quality of ceramic materials meets high standards, avoiding quality fluctuations caused by excessive or improper operation in traditional staged operations.

[0029] 4. Support large-size sample application: The system breaks through the limitations of traditional differential thermal analysis (DTA) in large-size sample testing, so that the debinding and sintering processes of large-size ceramic samples can also be accurately controlled, meeting the needs of large samples in industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0031] Figure 1 It is a structural schematic diagram of the ceramic debinding and sintering integrated system of the present invention;

[0032] Figure 1In the figure, 1 is a heating furnace, 2 is a partition component, 3 is a first furnace chamber, 4 is a second furnace chamber, 5 is a heating device, 6 is a high-temperature electronic balance, 7 is a stand, 8 is a base, 9 is a light source, 10 is a high-speed camera, 11 is a transparent window, and 12 is a ceramic sample;

[0033] Figure 2 Analyze the force state of an object;

[0034] Figure 3 The quality monitoring data of the ceramic sample in Example 1 of the present invention;

[0035] Figure 4 The size detection data of the ceramic sample in Example 1 of the present invention;

[0036] Figure 5 The quality inspection data without placing ceramic samples in Example 2 of the present invention;

[0037] Figure 6 is the mass calibration data of the ceramic sample in Example 1 of the present invention;

[0038] Figure 7 The quality monitoring data of the ceramic sample in Example 3 of the present invention;

[0039] Figure 8 is the mass calibration data of the ceramic sample in Example 3 of the present invention;

[0040] Fig. 9 is the air density at each moment in Example 4 of the present invention;

[0041] Fig.10 is the sample mass change rate caused by the change of air buoyancy in Example 4 of the present invention;

[0042] Fig.11 This is the mass calibration data of the ceramic sample that only undergoes air buoyancy calibration in Example 1 of the present invention. DETAILED DESCRIPTION

[0043] The present invention provides a ceramic debinding and sintering integrated process, using a ceramic debinding and sintering integrated system to heat a ceramic sample;

[0044] The ceramic debinding and sintering integrated system comprises a high-temperature furnace module, a quality measurement module, a dimension measurement module, and a data acquisition and processing module.

[0045] In the present invention, the high temperature furnace module comprises a heating furnace, and the heating furnace comprises a partition component, which divides the heating furnace into two sealed spaces, the first furnace cavity located at the upper part of the heating furnace and the second furnace cavity located at the lower part of the heating furnace.

[0046] In the present invention, a ceramic sample is placed in the first furnace cavity; a heating device is arranged outside the first furnace cavity, and the heating device has a precise temperature control function and can heat large-sized ceramic samples under high temperature conditions; a transparent window is arranged on the cavity wall of the first furnace cavity to allow light to pass through.

[0047] In the present invention, a high-temperature electronic balance is placed in the second furnace chamber. During the heating process, the partition component can isolate the heat radiation from the first furnace chamber, ensuring that the ambient temperature in the second furnace chamber where the high-temperature electronic balance is located is below 200°C, ensuring that the high-temperature electronic balance is not affected by high temperature.

[0048] In the present invention, the mass measurement module includes a high-temperature electronic balance and a ceramic sample support device, which can measure the mass change data of the sample in real time.

[0049] In the present invention, the high temperature electronic balance is placed in the second furnace cavity. The present invention has no special restrictions on the model of the high temperature electronic balance. Specifically, in an embodiment of the present invention, the measurement range of the high temperature electronic balance is 0~200g, and the measurement accuracy is 10mg.

[0050] In the present invention, the high temperature electronic balance and the ceramic sample to be heated are not in the same space, so that the debinding and sintering can be monitored simultaneously.

[0051] In the present invention, the ceramic sample support device includes a base and a frame; the base is located in the first furnace cavity and is used to place ceramic materials; one end (bottom end) of the frame is connected to a high-temperature electronic balance and supported by the high-temperature electronic balance, passes through a partition component, and extends vertically into the first furnace cavity, and the other end (top end) holds up the base for placing ceramic samples.

[0052] In the present invention, the base is preferably a corundum gasket, and the corundum gasket is preferably prepared by isostatic pressing process, and the frame is preferably a corundum frame.

[0053] In the present invention, the size measurement module includes an optical measuring device, which includes a light source and a high-speed camera; the light source and the high-speed camera are arranged outside the transparent window of the first furnace chamber, and the light from the light source is irradiated onto the ceramic sample through the transparent window. Based on this, the high-speed camera can collect images of the ceramic sample in real time, thereby obtaining data on changes in the size of the ceramic sample.

[0054] In the present invention, the data acquisition and processing module synchronously acquires mass change and size change data, and stores and analyzes the data.

[0055] In the present invention, the ceramic sample is placed on the base, and the first furnace cavity and the second furnace cavity are ensured to be sealed, and the heating device can be turned on to heat the ceramic sample.

[0056] In the present invention, the holding temperature of the heating treatment is preferably 1500-1600°C, more preferably 1550-1580°C, such as 1500°C, 1510°C, 1520°C, 1530°C, 1540°C, 1550°C, 1560°C, 1570°C, 1580°C, 1590°C, 1600°C, preferably a range value with any of the above values ​​as the upper or lower limit, the holding time of the heating treatment is preferably 1-5 hours, more preferably 2-4 hours, most preferably 2-3 hours, and the heating treatment comprises In the process of heating from room temperature to the holding temperature, the heating rate of the heat treatment is 1-15°C / min, more preferably 2-10°C / min, such as 1°C / min, 2°C / min, 3°C / min, 4°C / min, 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min, 10°C / min, 11°C / min, 12°C / min, 13°C / min, 14°C / min, 15°C / min, preferably with any of the above values ​​as the upper or lower limit of the range value.

[0057] The present invention also provides a method for synchronous analysis of high temperature deformation and thermal weight loss of ceramics, comprising the following steps:

[0058] A) heating the ceramic sample according to the ceramic debinding and sintering integrated process described above;

[0059] B) using the mass measurement module to collect the mass change data of the ceramic sample in real time, and the size measurement module to collect the size change data in real time;

[0060] C) Use the data acquisition and processing module to analyze the mass change data and size change data.

[0061] In the present invention, in step B), a size measurement module is used to collect images of the ceramic sample in real time during the heating process, and the size change data of the ceramic sample is obtained through an image recognition algorithm, and a temperature-size change curve of the ceramic sample is drawn based on the real-time collected size change data of the ceramic sample.

[0062] In the present invention, a mass measurement module is used to collect the mass change data of the ceramic sample in real time, and a temperature-mass change curve of the ceramic sample is drawn based on the real-time collected mass change data of the ceramic sample.

[0063] In the present invention, the mass change data obtained in step B), ie, the temperature-mass change curve of the ceramic sample, is preferably calibrated and then used for the data analysis in step C).

[0064] The calibration preferably includes: heating the ceramic debinding and sintering integrated system without placing a ceramic sample according to the ceramic debinding and sintering integrated process described above; the mass measurement module real-time collects the mass change data of the high-temperature electronic balance, and draws a temperature-mass change curve for calibration based on the real-time collected mass change data of the high-temperature electronic balance;

[0065] The mass change data of the ceramic sample is subtracted from the mass change data used for calibration at the same temperature to obtain the mass change data of the calibrated ceramic sample, and the temperature-mass change curve of the calibrated ceramic sample is plotted based on the data.

[0066] The thermal behavior of the ceramic samples is analyzed according to the temperature-size change curve of the ceramic samples and the temperature-mass change curve of the calibrated ceramic samples. Then, based on the analysis results, the ceramic debinding and sintering processes are optimized, such as adjusting parameters such as sintering temperature, heating rate and holding time, to further improve product quality and production efficiency.

[0067] In order to further illustrate the present invention, a ceramic debinding and sintering integrated process and a ceramic high-temperature deformation and thermal weight loss simultaneous analysis method provided by the present invention are described in detail below in conjunction with embodiments, but it should not be understood as limiting the scope of protection of the present invention.

[0068] Example 1

[0069] Step 1: Select alumina ceramic powder with an average particle size of 200 nm (purity of 99.99%);

[0070] Step 2: Prepare alumina / polyvinyl alcohol ceramic granulated powder by manual granulation method; wherein the mass fraction of polyvinyl alcohol is 5.1%.

[0071] Step 3: Weigh a certain mass of ceramic granulation powder, fill it into a steel mold, and use a press to press the ceramic granulation powder into a ceramic green body with a diameter of 20 mm and a height of 10 mm at a pressure of 100 MPa; test the initial weight and size of the ceramic sample;

[0072] Step 4: Adoption Figure 1 The device shown performs debinding and sintering on the ceramic green body, and places the ceramic green body on the corundum gasket of the sintering furnace, the length and width of the corundum gasket are both 20 mm, the height = 2 mm, and the initial mass is set to the mass of the ceramic green body;

[0073] Step 5: Heating to 1550°C at a heating rate of 10°C / min, keeping the temperature for 180 min, and cooling to room temperature at a cooling rate of 3°C / min;

[0074] Step 6: Test the final size and weight of the ceramic sample, and compare them with the initial weight and size to find out the actual mass change rate and size change rate. The actual mass and size change rates of the sample are 5.1% and 18% respectively.

[0075] Step 7: Analyze the real-time monitoring data of quality and size, and compare them with the actual size change rate and quality change rate.

[0076] In Example 1, the quality change data monitored in real time by the ceramic debinding and sintering integrated optimization system is as follows: Figure 3 As shown, the size change data is as follows Figure 4 As shown in the figure, it can be found that the size change is basically consistent with the actual size change rate, but there is a certain error between the maximum mass change and the actual maximum mass change rate. The maximum mass change rate monitored in real time by the ceramic debinding and sintering integrated optimization system is 4.6791%. The accuracy rate is 91.74% (4.6791 / 5.1=0.917).

[0077] Example 2

[0078] Step 1: Figure 1 The device shown does not contain a sample, but only an empty corundum gasket. The length and width of the corundum gasket are both 20 mm, and the height = 2 mm. The initial mass of the balance is set to the mass of the corundum gasket;

[0079] Step 2: Heating to 1550°C at a heating rate of 10°C / min, keeping at that temperature for 180min, and then cooling to room temperature at a cooling rate of 3°C / min;

[0080] Step 3: Test the final weight of the corundum gasket and compare it with the real-time monitoring data.

[0081] In Example 2, the corundum gasket was measured before and after sintering, and it was found that the actual quality of the corundum gasket did not change. However, the quality data monitored by the ceramic debinding and sintering integrated optimization system changed, such as Figure 5 shown.

[0082] The mass data of the ceramic sample monitored in real time in Example 1 is subtracted from the mass data of the ceramic sample monitored in real time in Example 2 at the same temperature to obtain the calibrated mass change curve of the ceramic sample in Example 1 ( Figure 6 ), and compared it with its actual maximum mass change rate. The maximum mass change of the ceramic sample after calibration in Example 1 is 5.26%, and the accuracy is 103% (5.26 / 5.1=1.03).

[0083] Example 3

[0084] Step 1: Select alumina ceramic powder with an average particle size of 200 nm (purity of 99.99%);

[0085] Step 2: Prepare alumina / polyvinyl alcohol ceramic granulation powder by manual granulation method; wherein the mass fraction of polyvinyl alcohol is 25%

[0086] Step 3: Weigh a certain mass of ceramic granulation powder, fill it into a steel mold, and use a press to press the ceramic granulation powder into a ceramic green body with a diameter of 20 mm and a height of 10 mm at a pressure of 100 MPa; test the initial weight and size of the ceramic sample;

[0087] Step 4: Place the ceramic green body on the corundum gasket of the sintering furnace. The length and width of the corundum gasket are both 20 mm, and the height is 2 mm. The initial mass is set to the mass of the ceramic green body.

[0088] Step 5: Heating to 1550°C at a heating rate of 10°C / min, keeping the temperature for 180 min, and cooling to room temperature at a cooling rate of 3°C / min;

[0089] Step 6: Test the final weight of the ceramic sample and compare it with the initial weight to find out the actual mass change. The actual mass change rate of the sample is 25%;

[0090] Step 7: Analyze the real-time monitoring data of quality and compare it with the actual quality change rate.

[0091] In Example 3, the quality change data monitored in real time by the ceramic debinding and sintering integrated optimization system is as follows: Figure 7 The maximum mass change rate monitored by the integrated optimization system for debinding and sintering of ceramics in real time is 23.2%, and the accuracy is 92.8% (23.2 / 25=0.928).

[0092] The mass data of the ceramic sample monitored in real time in Example 3 is subtracted from the mass data of the ceramic sample monitored in real time in Example 2 at the same temperature to obtain the calibrated mass change curve of the ceramic sample in Example 3 ( Figure 8 ), after calibration using the calibration data in Example 2, the maximum mass change rate of the sample is 23.78% ( Figure 8 ), the accuracy rate is 95.12% (23.78 / 25=0.9512).

[0093] Example 4

[0094] Step 1. Use the ideal gas equation to calculate the change in air density during heating:

[0095] (1)

[0096] Where ρ is the air density, V is the air volume, R is the gas constant, and T is the temperature. The air density at different temperatures is:

[0097] (2)

[0098] Where ρ1 is the initial air density and T1 is the initial temperature. ρ2 is the final air density and T2 is the final temperature. The air density at each moment can be obtained using equation (3): Fig. 9 Shown

[0099] Step 2: Calculate the mass change caused by the change in air density during heating:

[0100] (3)

[0101] Among them, V2 and V1 are the volume changes of the sample. The size measurement module in the ceramic debinding and sintering integrated optimization system can be used to measure the size changes of the cylindrical ceramic sample in the width and height directions, and calculate the volume change of the cylindrical sample. At each temperature, the sample mass change rate due to the change in air buoyancy is as follows: Fig.10 shown.

[0102] Step 3: Subtract the maximum mass change rate monitored in real time by the ceramic debinding and sintering integrated optimization system from the sample mass change rate caused by the air buoyancy change to calibrate the sample mass. Fig.11 shown.

[0103] In Example 4, the maximum mass change rate of the sample after calibration is 4.6794%, which is basically consistent with the maximum mass change rate (4.6791%) monitored in real time by the ceramic debinding and sintering integrated optimization system in Example 1, indicating that the effect of air buoyancy on mass measurement is very small. According to the above experimental results, compared with the influence of air buoyancy that is usually considered, factors such as air flow and device expansion have a greater impact on mass measurement.

[0104] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A ceramic debinding and sintering integrated process, characterized in that: The ceramic samples were heated using the ceramic debinding and sintering integrated system; The ceramic debinding and sintering integrated system includes a high-temperature furnace module, a quality measurement module, a size measurement module, and a data acquisition and processing module; The high-temperature furnace module comprises a heating furnace, and the heating furnace comprises a partition component, and the partition component divides the heating furnace into two sealed spaces, the first furnace cavity located at the upper part of the heating furnace, and the second furnace cavity located at the lower part of the heating furnace; a heating device is arranged outside the first furnace cavity; The mass measurement module includes a high-temperature electronic balance and a ceramic sample support device, the high-temperature electronic balance is placed in the second furnace cavity, and the ceramic sample support device includes a base and a frame; the base is located in the first furnace cavity and is used to place ceramic materials; the frame passes through the partition component, one end of which is connected to the base, and the other end is connected to the high-temperature electronic balance; The heat preservation temperature of the heating treatment is 1500-1600° C., and the heating rate of the heating treatment is 1-15° C. / min.

2. The ceramic debinding and sintering integrated process according to claim 1, characterized in that: The base is a corundum gasket, and the seat frame is a corundum seat frame.

3. The ceramic debinding and sintering integrated process according to claim 1, characterized in that: The dimension measurement module comprises an optical measurement device, and the optical measurement device comprises a light source and a high-speed camera.

4. The ceramic debinding and sintering integrated process according to claim 3, characterized in that: The outer wall of the first furnace cavity is provided with a transparent window, and an optical measuring device is arranged outside the transparent window.

5. The ceramic debinding and sintering integrated process according to claim 1, characterized in that: Using a heating device to heat the first furnace chamber to perform a heating treatment on the ceramic material; The temperature in the second furnace chamber is lower than 200°C.

6. The ceramic debinding and sintering integrated process according to claim 1, characterized in that: The heat preservation time of the heating treatment is 1 to 5 hours.

7. A method for simultaneous analysis of high temperature deformation and thermal weight loss of ceramics, comprising the following steps: A) heating the ceramic sample according to the ceramic debinding and sintering integrated process according to claim 1; B) using the mass measurement module to collect the mass change data of the ceramic sample in real time, and the size measurement module to collect the size change data in real time; C) Use the data acquisition and processing module to analyze the mass change data and size change data.

8. The method for simultaneous analysis of ceramic high temperature deformation and thermal weight loss according to claim 7, characterized in that: In the step B), a size measurement module is used to collect images of the sample in real time during the heating process, and size change data is obtained through an image recognition algorithm.

9. The method for simultaneous analysis of ceramic high temperature deformation and thermal weight loss according to claim 7, characterized in that: According to the real-time collected mass change data and size change data of the ceramic samples, a temperature-mass change curve and a temperature-size change curve are drawn.

10. The ceramic high temperature deformation and thermal weight loss simultaneous analysis method according to claim 7, characterized in that: Calibrate the mass change data obtained in step B) and use it for data analysis in step C); The calibration comprises: heating the ceramic debinding and sintering integrated system without placing a ceramic sample according to the ceramic debinding and sintering integrated process of claim 1; the mass measurement module collects the mass change data of the high-temperature electronic balance in real time to obtain calibration data; The calibration data at the same temperature is subtracted from the ceramic sample mass change data to obtain the calibrated ceramic sample mass change data.

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