A sintering furnace hearth multi-region calibration sample placing device and method

Abstract

The application discloses a sintering furnace hearth multi-region calibration sample placing device and method, and belongs to the technical field of MIM product sintering. The sintering furnace hearth multi-region calibration sample placing device comprises a round cake-shaped device body, and a boss is formed by protruding outward from the middle part of the surface of one side of the device body; the upper surface of the boss is a hardness detection part; the calibration method of the placing device comprises the following steps: dividing a calibration region; placing the device body and sintering; performing multi-index directional detection on the device body; recording detection values; determining a hearth operation state and adjusting hearth abnormalities. The application uses the cooperation of the sintering furnace hearth multi-region calibration sample placing device and the method, can calibrate the temperature, carbon potential and airflow distribution of the sintering furnace hearth, timely discovers abnormalities and adjusts them, avoids low product qualification rate caused by direct sintering products, and simultaneously uses the calibration region to reflect the sintering state of the whole hearth, uses a part to replace a whole, and saves calibration cost.

Description

Technical Field

[0001] This invention relates to the field of MIM product sintering technology, and in particular to a multi-zone calibration and placement device and method for the furnace chamber of a sintering furnace. Background Technology

[0002] Metal powder injection molding (MIM) is a novel near-net-shape forming technology that combines plastic injection molding with powder metallurgy. The basic process involves: first, uniformly mixing solid powder with an organic binder; then granulating the mixture and injecting it into a mold cavity under heating and plasticizing conditions; finally, removing the binder from the preform using chemical or thermal decomposition methods; and finally, sintering to densify the product. During the sintering process, uneven distribution of temperature, carbon potential, and airflow within the furnace can lead to significant differences in the size, carbon content, or corrosion resistance of the sintered product, resulting in a low product yield. Therefore, calibrating the sintering furnace before sintering, identifying and adjusting any abnormalities, can improve sintering quality, increase the product yield, and prevent products from being scrapped due to undersized dimensions or excessive carbon content. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a multi-zone calibration method and usage method for sintering furnace lining that can overcome or at least partially solve the above problems.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A multi-region calibration sample placement device for sintering furnace lining is used to calibrate the sintering furnace lining before sintering samples and determine whether the lining is in optimal condition. The device includes a disc-shaped main body, with a protrusion formed by an outward protrusion on the middle of one side surface of the main body; the upper surface of the protrusion is a hardness detection part.

[0005] Furthermore, the boss has a central through hole in the middle, which allows for the flow of gas inside and outside the device body and provides force support for picking up the device body.

[0006] Preferably, a circular bottom groove is provided in the middle of the other side of the device body, and a ventilation groove is provided at the bottom for the bottom groove to communicate with the outside.

[0007] Preferably, the device body is provided with a waist-shaped positioning groove for positioning the device body.

[0008] Furthermore, a support body is provided inside the bottom groove. The support body is annular, and its outer diameter matches the diameter of the hardness detection part.

[0009] Furthermore, the calibration method for the placement device is characterized by: Step 1: Select the bottom, middle and top layers of the sintering furnace as characteristic layers in the height direction; select the head, front middle, rear middle and tail sections as characteristic segments in the length direction; combine the three characteristic layers and four characteristic segments to form 12 calibration areas; Step 2: Place the device body in each calibrated area, sinter the device body according to the normal sintering process, and then remove it; Step 3: Perform multi-index directional testing on the device body; Step 4: Record the test data into the inspection record file; Step 5: Determine the operating status of the furnace based on the inspection record documents and make adjustments to the sintering furnace.

[0010] Furthermore, five device bodies are placed in each calibration area, symmetrically arranged in the upper left, lower left, upper right, lower right and middle positions of the calibration area.

[0011] Furthermore, step three includes multiple indicators such as size, density, hardness, and carbon content.

[0012] Furthermore, the method for determining the operating status of the furnace in step five is as follows: If the device body is too large, and its density and hardness are too low, but its carbon content is normal, then the sintering temperature of the calibration area where the device body is located is too low. If the size and density of the device body are normal, but the hardness and carbon content are low, then the carbon potential of the calibration area where the device body is located is low. If the size, density, and carbon content of five samples within the same calibration area vary greatly, it is determined that the airflow in the furnace is not smooth or the carbon potential distribution is uneven.

[0013] Preferably, it also includes: generating a furnace calibration area status distribution map based on the detection data, which is used to visually display the sintering status of each calibration area and to enable the traceability of historical data.

[0014] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: 1. This invention, through the design of a multi-zone calibration sample placement device in the sintering furnace chamber, can calibrate the temperature, carbon potential, and airflow distribution in the sintering furnace chamber, promptly detect abnormalities and make adjustments, and avoid direct sintering of products, which would result in low product qualification rate, and products that are too small or have excessive carbon content may even be scrapped, causing waste.

[0015] 2. The design of the boss on the device body forms a hardness testing section, providing a testing location for the hardness testing of the device body. This avoids the lack of comparability and reference data due to different testing positions. The design of the support body in the bottom groove provides support for the hardness testing section, preventing the device body from deforming or breaking during hardness testing, which would distort the test results.

[0016] 3. By utilizing the design of a multi-region calibration method for the sintering furnace lining, the characteristic layers and sections of the sintering furnace lining are calibrated. By performing multi-index testing on the calibrated areas, the overall condition of the furnace lining can be reflected, avoiding the waste of manpower and resources caused by placing a large number of items, while also increasing testing costs and reducing efficiency. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of a multi-region calibration sample placement device for a sintering furnace proposed in this invention, viewed from top to bottom. Figure 2 This is a three-dimensional structural diagram of a multi-region calibration sample placement device for a sintering furnace proposed in this invention, viewed from bottom to top. Figure 3 This is a three-dimensional structural diagram of a multi-region calibration sample placement device for a sintering furnace proposed in this invention, placed on a single sintering carrier plate. Figure 4 This is a logic flowchart of a multi-zone calibration method for a sintering furnace proposed in this invention. In the figure: 1. Device body; 2. Boss; 3. Hardness testing part; 4. Bottom groove; 5. Ventilation groove; 6. Positioning groove; 7. Central through hole; 8. Support body; 9. Sintered carrier plate. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] Example 1: refer to Figures 1-3A multi-region calibration sample placement device for sintering furnace lining is used to calibrate the sintering furnace lining before sintering samples and determine whether the lining is in optimal condition. The device includes a disc-shaped device body 1, with a protrusion 2 formed by an outward protrusion in the middle of one side surface of the device body 1; the upper surface of the protrusion 2 is a hardness detection part 3.

[0021] The present invention utilizes the design of the boss 2 on the device body 1 to form a hardness detection part 3, which provides a detection site for hardness detection of the device body 1, and avoids the lack of comparability of detection results and lack of reference due to different detection positions during detection. The boss 2 has a central through hole 7 in the middle. The central through hole 7 can allow gas to circulate inside and outside the device body 1, and can also provide force support for picking up the device body 1.

[0022] The design of the central through-hole 7 allows airflow to enter the bottom groove 4 during sintering, ensuring full contact with the device body 1 and improving the sintering effect. This avoids the impact of insufficient airflow in the bottom groove 4 on the sintering effect, which could lead to distortion of multiple indicators and render the test results meaningless. At the same time, it also allows air to be expelled from the bottom groove 4, preventing the internal air from expanding due to heat and causing deformation of the device body 1, thus avoiding dimensional data distortion. Furthermore, the central through-hole 7 facilitates handheld handling, preventing contact with the testing surface from causing dimensional data distortion.

[0023] It should be noted that the central through hole 7 adopts a circular structure. Its smooth flow channel can prevent the formation of eddies or turbulence in the furnace atmosphere, which would affect the sintering effect. In the low-speed atmosphere environment of the sintering furnace, the airflow passes through the through hole smoothly, eliminating the blocked area of ​​the central atmosphere of the sample, ensuring uniform carbon potential and temperature distribution, improving sintering consistency, and will not have an adverse effect on the sintering quality.

[0024] A circular bottom groove 4 is provided in the middle of the other side of the device body 1, and a ventilation groove 5 is provided at the bottom for the bottom groove 4 to communicate with the outside. The design of the circular bottom groove 4 allows the device body 1 to partially contact the sintering carrier plate 9, avoiding excessive contact area that could lead to sintering adhesion and damage to the device body 1 after it is removed from the sintering carrier plate 9, thus rendering it unusable for reference. The ventilation groove 5 increases the airflow channels within the bottom groove 4, allowing the airflow to contact the device body 1 more fully.

[0025] The device body 1 is provided with a waist-shaped positioning groove 6 for the placement and positioning of the device body 1.

[0026] The positioning groove 6 enables the device body 1 to be stably placed on the sintering carrier plate 9, avoiding the device body 1 from shifting or moving and causing friction and collision, which would damage the device body 1. At the same time, by setting positioning bodies that match the positioning groove 6 at the same position on different sintering carrier plates 9, the placement position of the device body 1 on different feature layers can be controlled to be relatively uniform, which is more accurate when comparing multiple indicators and makes subsequent furnace adjustments more precise.

[0027] The bottom groove 4 is equipped with a support body 8, which is ring-shaped and whose outer diameter matches the diameter of the hardness detection part 3.

[0028] The outer diameter of the support body 8 matches the diameter of the hardness testing part 3, that is, the support body 8 is located directly below the hardness testing part 3. It provides support for the hardness testing part 3 during sintering and hardness testing, so as to prevent the device body 1 from deforming or breaking during sintering or hardness testing, which would cause the test results to be distorted.

[0029] This invention, through the design of a multi-zone calibration sample placement device in the sintering furnace chamber, can calibrate the temperature, carbon potential, and airflow distribution in the sintering furnace chamber, promptly detect abnormalities and make adjustments, and avoid direct sintering of products, which would result in low product qualification rate, and products that are too small or have excessive carbon content may even be scrapped, causing waste.

[0030] Example 2: refer to Figure 4 Based on Example 1, the calibration method for the placement device is further characterized by: Step 1: Select the bottom, middle and top layers of the sintering furnace as characteristic layers in the height direction; select the head, front middle, rear middle and tail sections as characteristic segments in the length direction; combine the three characteristic layers and four characteristic segments to form 12 calibration areas; It should be noted that within the same layer of the furnace, two sintering carrier plates 9 can be arranged, one in front and one in back. The front end (front third) and the rear end (rear third) of the two sintering carrier plates 9 are respectively taken to form four characteristic sections: head, middle front, middle rear and tail. If there is one or more sintering carrier plates 9 in the same layer, the same characteristic section selection method can be used to divide two or more characteristic sections.

[0031] By utilizing the design of a multi-region calibration method for the sintering furnace lining, characteristic layers and sections of the sintering furnace lining are calibrated. By performing multi-index testing on the calibrated areas, the overall condition of the furnace lining can be reflected, avoiding the waste of manpower and resources caused by placing a large number of items, while also increasing testing costs and reducing efficiency.

[0032] Step 2: Place the device body 1 in each calibrated area, sinter the device body 1 according to the normal sintering process, and then remove it; Step 3: Perform multi-index directional testing on the device body 1; Step 4: Record the test data into the inspection record file; The calibration areas can be numbered as follows: the head, front middle, rear middle, and tail can be numbered a, c, d, and e respectively; the bottom, middle, and top layers can be numbered A, B, and C respectively. In this way, the furnace is divided into 12 calibration areas: Aa, Ab, Ac, Ad, Ba, Bb, Bc, Bd, Ca, Cb, Cc, and Cd. In this way, the test data of the device body 1 in each calibration area can be clearly and accurately recorded in the inspection record file, avoiding misrecording and omissions.

[0033] Step 5: Determine the operating status of the furnace based on the inspection record documents and make adjustments to the sintering furnace.

[0034] Five device bodies 1 are placed in each calibration area, symmetrically arranged in the upper left, lower left, upper right, lower right and middle positions of the calibration area.

[0035] Similarly, the device body 1 in the upper left, lower left, upper right, lower right and middle positions can be numbered as I, II, III, IV and V respectively, which facilitates statistical recording.

[0036] By placing five device bodies 1 in each calibration area, the entire spatial range of the calibration area is fully covered, avoiding the problem that data from a single point cannot represent the overall temperature field, carbon potential, and airflow distribution of the area. The arithmetic mean of the five test data is calculated to eliminate errors caused by accidental factors such as minor defects of the individual sample, local dust adhesion, and test operation deviations, making the final calibration data of a single calibration area more accurate.

[0037] Step three involves multiple indicators, including size, density, hardness, and carbon content.

[0038] Dimensions can be measured using vernier calipers; density can be measured using alcohol as a medium via the Archimedes method; hardness is tested using Vickers hardness (HV0.5) at a test force of 0.5 kgf; and carbon content is measured using high-frequency infrared absorption.

[0039] It should be noted that the size and density need to be measured for each device body 1, and then the arithmetic mean of each calibration area is used as the representative value of that calibration area; hardness and carbon content are measured only for a single device body 1, for example: only the hardness of device body 1 of device III in each calibration area is measured, and the carbon content of device body 1 of device V is measured, to avoid increasing the detection time and cost by testing all devices; when the measurement result of a single device body 1 has too large an error, the correctness of the test result can be judged by re-measuring other devices (such as device II).

[0040] The method for determining the operating status of the furnace in step five is as follows: If the size of the device body 1 is too large, and the density and hardness are too low, but the carbon content is normal, then the sintering temperature of the calibration area where the device body 1 is located is too low. If the size and density of the device body 1 are normal, but the hardness and carbon content are low, then the carbon potential of the calibration area where the device body 1 is located is low. If the size, density, and carbon content of five samples within the same calibration area vary greatly, it is determined that the airflow in the furnace is not smooth or the carbon potential distribution is uneven.

[0041] Before sintering calibration, a standard value and allowable error can be preset. By comparing the error between the test data and the standard value, it can be determined whether the device body 1 is qualified. If it is not qualified, it indicates that the furnace condition is abnormal and the furnace needs to be adjusted.

[0042] Example 3: Based on Example 2, the calibration method of the device further includes: generating a state distribution map of the furnace calibration area based on the detection data, which is used to visually display the sintering state of each calibration area and to trace historical data.

[0043] By transforming test data into a state distribution map of the furnace calibration area, abstract test data such as size, density, hardness, and carbon content are converted into intuitive graphical distributions, replacing cumbersome data tables and clearly displaying the sintering state of each calibration area in the furnace at a glance. Through differences in graphic color or markings, calibration areas and specific locations with abnormal temperatures, carbon potential, and uniformity can be directly identified without the need for individual data verification and comparison, significantly improving the efficiency of anomaly judgment. At the same time, it can also completely retain the state distribution graphics of each batch of calibrations, enabling long-term traceability of furnace state changes and providing data support for sintering furnace process optimization and equipment maintenance.

[0044] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A multi-zone calibration sample placement device for a sintering furnace lining, used to calibrate the sintering furnace lining before sintering samples and determine whether the lining is in optimal condition, characterized in that... The device includes a disc-shaped device body (1), and a boss (2) is formed by protruding outward from the middle of one side surface of the device body (1); the upper surface of the boss (2) is a hardness detection part (3).

2. The multi-zone calibration sample placement device for a sintering furnace according to claim 1, characterized in that, The boss (2) has a central through hole (7) in the middle. The central through hole (7) can realize the flow of gas inside and outside the device body (1) and can also provide force support for taking the device body (1).

3. The multi-zone calibration sample placement device for a sintering furnace according to claim 2, characterized in that, A circular bottom groove (4) is provided in the middle of the other side of the device body (1), and a ventilation groove (5) is provided at the bottom for the bottom groove (4) to communicate with the outside.

4. The multi-zone calibration sample placement device for a sintering furnace according to claim 3, characterized in that, The device body (1) is provided with a waist-shaped positioning groove (6) for the placement and positioning of the device body (1).

5. The multi-zone calibration sample placement device for a sintering furnace according to claim 3, characterized in that, The bottom groove (4) is provided with a support body (8), which is ring-shaped and whose outer diameter matches the diameter of the hardness detection part (3).

6. A multi-zone calibration sample placement device for a sintering furnace according to any one of claims 1 to 5, characterized in that, The calibration method for this placement device is as follows: Step 1: Select the bottom, middle and top layers of the sintering furnace as characteristic layers in the height direction; select the head, front middle, rear middle and tail sections as characteristic segments in the length direction; combine the three characteristic layers and four characteristic segments to form 12 calibration areas; Step 2: Place the device body (1) in each calibrated area, sinter the device body (1) according to the normal sintering process, and then take it out; Step 3: Perform multi-index directional testing on the device body (1); Step 4: Record the test data into the inspection record file; Step 5: Determine the operating status of the furnace based on the inspection record documents and make adjustments to the sintering furnace.

7. The method for calibrating a multi-zone sintering furnace according to claim 6, characterized in that, The number of device bodies (1) placed in each calibration area is five, symmetrically arranged in the upper left, lower left, upper right, lower right and middle positions of the calibration area.

8. The method for calibrating a multi-zone sintering furnace according to claim 6, characterized in that, Step three involves multiple indicators, including size, density, hardness, and carbon content.

9. A multi-zone calibration method for a sintering furnace lining according to claim 6, characterized in that, The method for determining the operating status of the furnace in step five is as follows: If the size of the device body (1) is too large, the density and hardness are too low, but the carbon content is normal, then the sintering temperature of the calibration area where the device body (1) is located is too low. If the size and density of the device body (1) are normal, but the hardness and carbon content are low, then the carbon potential of the calibration area where the device body (1) is located is low. If the size, density, and carbon content of five samples within the same calibration area vary greatly, it is determined that the airflow in the furnace is not smooth or the carbon potential distribution is uneven.

10. A multi-zone calibration method for a sintering furnace lining according to claim 6, characterized in that, Also includes: A furnace calibration area status distribution map is generated based on the test data to visually display the sintering status of each calibration area and to enable the traceability of historical data.

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