Thermal vibration synergistic hard alloy anvil residual stress eliminating method and eliminating device

Abstract

The invention provides a thermal vibration synergistic hard alloy anvil residual stress eliminating method. The method comprises the steps that a hard alloy anvil is subjected to thermal treatment; and in the cooling process of the heat treatment, when the temperature of the hard alloy anvil is reduced to 150-200 DEG C, vibration aging treatment is applied to the hard alloy anvil. Vibration aging is precisely cut into a specific low-temperature window 150-200 DEG C in the heat treatment cooling process, the characteristic that the yield limit of a material at the temperature is reduced is utilized, external dynamic stress and internal residual stress are optimally superposed, deeper and more uniform microcosmic plastic flow is triggered, and the heat treatment effect is improved. Therefore, the stress elimination effect far better than that of simple superposition of a single process is realized; the highest treatment temperature of the whole process is far lower than the temperature of obvious structure transformation or softening of the hard alloy, and the problems of hardness reduction, oxidation, grain coarsening and the like caused by traditional high-temperature thermal aging are fundamentally avoided.

Description

Technical Field

[0001] This invention relates to the field of superhard materials technology, and in particular to a residual stress relief device and method. Background Technology

[0002] Carbide anvils are 2-inch cubes (length, width, and height) manufactured through powder metallurgy sintering and precision machining, using refractory carbides such as tungsten carbide (WC) as the hard phase and metals such as cobalt (Co) as the binder phase. The anvil face is typically an equilateral triangle formed by cutting off a corner from the cube's apex. Due to their high hardness and wear resistance, they are widely used in high-pressure applications. However, the high-pressure assembly process of carbide anvils requires eight anvils to form an assembly, and each anvil face needs to generate significant pressure. Therefore, after high-pressure assembly, each anvil is prone to developing a complex three-dimensional residual stress field. These residual stresses can lead to deformation and cracking during service, accelerating fatigue failure and severely impacting their service life and operational stability.

[0003] Currently, methods for eliminating residual stress in cemented carbide anvils mainly include single thermal aging, single vibration aging, and natural aging. Among them: single thermal aging releases stress through high-temperature holding (usually 500-650℃), but it has drawbacks such as high energy consumption, long processing cycle (20-60 hours), and easy oxidation and hardness reduction on the anvil surface, affecting the service life and core performance of the anvil; single vibration aging uses the dynamic stress generated by resonance to relax residual stress, which has low energy consumption and high efficiency, but it does not completely eliminate deep residual stress inside the cemented carbide and is not targeted enough to stress concentration areas; natural aging relies on time to release stress naturally, with a cycle of more than half a year, which is extremely inefficient and cannot meet the needs of industrial mass production.

[0004] Patent CN108774667A, published on November 9, 2018, discloses a device and method for stress relief using a combination of thermal aging and vibration aging. This device includes a vibration system, a heating system, and a cooling system. The cooling system cools the vibration table in the vibration system, and the exciter and sensor are fixed to the cooling end of the vibration table. A workpiece fixing device fixes the workpiece on the vibration table and extends it into the furnace cavity of a high-temperature furnace in the heating system, thus achieving stress relief through the combined effects of thermal aging and vibration aging. However, this method is not suitable for stress relief of cemented carbide anvils. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a thermally-vibration-coordinated method and device for eliminating residual stress in cemented carbide anvils, which solves the problem that existing thermally-vibration-coordinated stress elimination methods are not suitable for eliminating stress in cemented carbide anvils.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] A method for eliminating residual stress in a cemented carbide anvil using a combination of thermal vibration and mechanical stress aging includes: heat-treating the cemented carbide anvil; and applying vibration aging treatment to the cemented carbide anvil during the cooling process of the heat treatment, when the temperature of the cemented carbide anvil drops to the range of 150°C to 200°C. This invention precisely integrates vibration aging into a specific low-temperature window of 150-200°C during the heat treatment cooling process. Utilizing the characteristic that the yield strength of the material decreases at this temperature, it achieves optimal superposition of external dynamic stress and internal residual stress, inducing deeper and more uniform microscopic plastic flow, thereby achieving a stress elimination effect far exceeding that of simple superposition of single processes. The highest processing temperature of the entire process in this invention is far lower than the temperature at which cemented carbide undergoes significant microstructural transformation or softening (typically >500°C), fundamentally avoiding problems such as decreased hardness, oxidation, and grain coarsening caused by traditional high-temperature thermal aging.

[0008] Furthermore, the heat treatment includes a stepped heating process:

[0009] (1) Heat the cemented carbide anvil to a first temperature T1 and keep it at that temperature;

[0010] (2) The cemented carbide anvil processed in step (1) is further heated to a second temperature T2 and kept at that temperature, wherein T2 is higher than T1 but not higher than 200°C;

[0011] (3) Begin the cooling process.

[0012] Further, in step (1), the first temperature T1 is 90-110℃ and the holding time is 60-90 minutes; in step (2), the second temperature T2 is 150-190℃ and the holding time is 700-750 minutes.

[0013] Furthermore, the rate of heating from room temperature to T1 is controlled at 3-5℃ / min; the rate of heating from T1 to T2 is controlled at 2-3℃ / min.

[0014] Furthermore, the cooling rate of the cooling process in step (3) is controlled at 1-2℃ / min.

[0015] Furthermore, before performing the vibration aging treatment, the natural frequency of the cemented carbide anvil is first identified by frequency sweep, and the excitation frequency is set based on the natural frequency; the excitation frequency is set within ±5Hz of the natural frequency, and the vibration amplitude is 0.1-0.5mm.

[0016] Furthermore, during the vibration aging treatment, the temperature of the cemented carbide anvil is maintained between 140°C and 200°C by controlling heating or cooling.

[0017] Furthermore, the duration of the vibration aging treatment is 60-120 minutes.

[0018] The device for eliminating residual stress in the thermally-vibrated cemented carbide anvil method described in any of the above includes a vibration table, an electric heating device arranged around the vibration table, a sample arranged on the vibration table and pressed by a pressure iron, an exciter and a pickup arranged on the vibration table, and a temperature sensor on the sample; a rubber pad is provided at the bottom of the vibration table.

[0019] Furthermore, it also includes a central control system, which is electrically connected to the electric heating device, vibrator, vibration pickup and temperature sensor.

[0020] The beneficial effects of this invention are:

[0021] 1. This invention precisely cuts vibration aging into a specific low-temperature window (150-200℃) during the heat treatment cooling process. By utilizing the characteristic that the yield limit of the material decreases at this temperature, the external dynamic stress and the internal residual stress are optimally superimposed, which triggers a deeper and more uniform microscopic plastic flow, thereby achieving a stress relief effect that far exceeds that of simple superposition of a single process.

[0022] 2. The highest processing temperature of the entire process of this invention (e.g., 190°C) is much lower than the temperature at which cemented carbide undergoes significant structural transformation or softening (usually >500°C), fundamentally avoiding problems such as decreased hardness, oxidation, and grain coarsening caused by traditional high-temperature thermal aging.

[0023] 3. This invention targets the complex three-dimensional stress field inside the cemented carbide anvil. By sweeping the frequency to identify the natural frequency and combining it with directional excitation, it can effectively act on the stress concentration area. At the same time, the synergistic mode of "low temperature heat treatment + dynamic vibration" avoids the risk of cracking or even "explosion" caused by uneven internal stress distribution during single high temperature heat treatment, resulting in high process safety.

[0024] 4. Compared with traditional high-temperature thermal aging, which takes tens of hours and consumes a lot of energy, and natural aging, which takes more than half a year, the total processing time of the method of the present invention is greatly shortened (about ten hours), and the main energy consumption is concentrated at a lower heat preservation temperature, resulting in a significant improvement in overall energy efficiency, which is more in line with the economic and timeliness requirements of industrial mass production.

[0025] 5. This invention achieves precise step heating and slow cooling through current-controlled heating, and forms a closed-loop controllable process system by combining real-time monitoring and dynamic adjustment of vibration parameters. The process parameter windows (such as temperature, frequency, and rate) have been experimentally verified, showing good repeatability and being able to stably achieve the expected stress relief and performance protection goals. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the residual stress relief device of the present invention;

[0028] Figure 2 This is a schematic diagram of the sample in Comparative Example 2 of the present invention;

[0029] Figure 3 This is a schematic diagram of the sample of Comparative Example 3 of the present invention.

[0030] In the diagram: 1. Electric heating element, 2. Rubber pad, 3. Pressure iron, 4. Sample, 5. Temperature sensor, 6. Fixture, 7. Vibrator, 8. Vibration pickup, 9. Central control system. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] like Figure 1 As shown, the residual stress relief device for the cemented carbide anvil used in this invention includes a vibration table, an electric heating device 1 arranged around the vibration table, a sample 4 placed on the vibration table and pressed by a pressure iron 3, an exciter 7 and a vibration pickup 8 placed on the vibration table, and a temperature sensor 5 is provided on the sample 4; a rubber pad 2 is provided at the bottom of the vibration table. The exciter 7 is fixed to the vibration table by a clamp 6.

[0033] Furthermore, the elimination device also includes a central control system 9, which is electrically connected to the electric heating device 1, the vibrator 7, the vibration pickup 8, and the temperature sensor 5. The vibration pickup 8 is a vibration sensor. The central control system 9 obtains the sample temperature through the temperature sensor 5; controls the heating temperature and heating rate of the electric heating device 1; obtains the vibration frequency through the vibration pickup 8; and controls the operating frequency of the vibrator 7.

[0034] The method for eliminating residual stress in a thermally induced shock-induced cemented carbide anvil according to the present invention comprises the following steps:

[0035] I. Workpiece Pretreatment and System Clamping

[0036] First, the surface of the cemented carbide anvil workpiece, sample 4, is cleaned to remove oil, impurities, and machining burrs. Then, the anvil workpiece is fixed to the vibration table of the vibration aging equipment using rigid clamps to ensure rigid contact between the anvil workpiece and the vibration table, preventing relative displacement or damage during vibration. Simultaneously, a vibration sensor, i.e., a vibration pickup 8, is installed on the vibration table, and a temperature sensor is installed on the surface of the anvil workpiece and connected to the control system for real-time monitoring of vibration acceleration and temperature parameters throughout the process.

[0037] II. Stepped Current Control Heating

[0038] Connect the clamped anvil workpiece to the electric heating device (e.g., via electrode contact or induction coil coupling) or to the electric heating device on the vibrating worktable, start the heating program, and execute the following precise temperature-controlled stepped heating-holding process:

[0039] 1. First stage of heating and holding: By applying current to the electric heating device, the anvil is uniformly heated from room temperature to 90-110℃ (preferably 100℃) at a rate of 3-5℃ / min. After reaching this temperature, it is held at this temperature for 60-90 minutes to allow the residual stress on the surface of the anvil to be initially relaxed.

[0040] 2. Second stage of heating and holding: Adjust the current parameters to control the anvil to continue heating at a slower rate of 2-3℃ / min to 150-190℃ (preferably 190℃). This temperature range is much lower than the temperature at which the cemented carbide undergoes structural changes, effectively reducing the resistance to internal dislocation movement without compromising hardness. After reaching this temperature, hold for an extended period of 700-750 minutes to lay the foundation for the full release of deep residual stress.

[0041] 3. Controlled cooling: After the heat preservation is completed, turn off or reduce the heating power, and control the anvil to start cooling at a slow rate of 1-2℃ / min through the auxiliary cooling system (or natural cooling). The goal is to reduce the temperature to the predetermined range of 150-200℃. This process is designed to avoid introducing new thermal stress due to sudden temperature changes.

[0042] III. Thermal Co-vibration Aging

[0043] When the anvil temperature drops to the predetermined hot state window (e.g., 150℃) during the controlled cooling process, the vibration aging equipment should be started immediately to execute the coordinated vibration process:

[0044] 1. Frequency Sweep Analysis and Frequency Fixation: The vibrator is controlled to sweep frequencies within the range of 50-500Hz. Simultaneously, data is fed back through a vibration sensor to identify the natural frequency of the workpiece under hot conditions (typically 70-80Hz). Then, the excitation frequency is set within ±5Hz of the natural frequency (e.g., 70Hz) to excite the workpiece in a sub-resonant state.

[0045] 2. Directional Excitation and Dynamic Maintenance: Based on the geometric characteristics and stress concentration areas of the anvil, the position or direction of the vibrator is adjusted to apply periodic dynamic stress with an amplitude of 0.1-0.5 mm. The dynamic stress superimposed on the residual stress inside the anvil induces slight plastic deformation in the high-stress area. The entire excitation process lasts 60-120 minutes. During this period, the system monitors the vibration acceleration (typically controlled at 5-15 m / s²) and anvil temperature in real time. Based on sensor feedback, the excitation frequency and amplitude can be dynamically fine-tuned, and the working temperature of the anvil can be dynamically maintained between 140-200℃ by adjusting the heating current or cooling rate, ensuring that it is always in an optimal "thermal synergy" state.

[0046] IV. Final Cooling and Post-processing

[0047] After the coordinated vibration aging is completed, first turn off the vibration equipment and exciter. Then, turn off the current-controlled heating device and allow the anvil to cool naturally to room temperature in air or a controlled environment. After cooling, remove the rigid fixtures, electrodes or induction coils, and all sensors in sequence. Finally, clean the surface of the anvil and inspect its appearance. This completes the entire residual stress relief process, and the workpiece can be transferred to the next process or used.

[0048] Example 1

[0049] (1) Raw material workpiece: WC-Co cemented carbide anvil (Co content 6wt%, size 51.2mm×51.2mm×51.2mm, residual stress value after high pressure synthesis is about -1156.00).

[0050] (2) Equipment: Intelligent vibration aging instrument (sweep frequency range 50-1000Hz, acceleration measurement range 0-50m / s²), current control heating system (temperature control accuracy ±3℃).

[0051] (3) The processing procedure is as follows:

[0052] S1 Pretreatment: The surface of the anvil is cleaned with alcohol to remove oil stains; a rigid clamp is used to clamp the anvil and the vibration table so that they can make rigid contact; a temperature sensor is installed on the surface of the anvil; a high-frequency induction coil is wrapped around the vibration table; and a vibration pickup, i.e., a vibration sensor, is installed.

[0053] S2 Current Controlled Heating: The induction heating device is activated, and the following settings and controls are implemented through the central control system: First stage: Heating to 100℃ at a rate of 5℃ / min, holding for 120min; Second stage: Adjusting the power, heating to 150℃ at a rate of 4℃ / min, holding for 120min, then heating to 190℃ at a rate of 2℃ / min, holding for 600min; Cooling process: Reducing the current power, and controlling the cooling rate to approximately 2℃ / min to 150℃ through natural cooling.

[0054] S3 Cooperative Vibration Aging: When the anvil temperature drops to 150℃, the vibration aging instrument is started. A 50-500Hz frequency sweep identifies the anvil's natural frequency as 73Hz. The excitation frequency is set to 70Hz, amplitude to 0.3mm, vibration acceleration to 10m / s², and excitation time to 90min. During this period, the temperature is maintained between 140-160℃.

[0055] S4 Cooling and Post-treatment: After vibration, reduce the current power and allow the anvil to cool naturally to 50°C. o C. Remove the clamps, coils / electrodes, and sensors; clean the surfaces. Place the anvil at a temperature of 50°C. o Store in a constant temperature room (C).

[0056] (4) Performance testing: The residual stress was measured by X-ray diffraction. The results showed that the average residual stress of the anvil was reduced to 863.63, the removal rate was 25.3%, and the high-temperature detection (HRA) was 89.5, which was basically consistent with the value before treatment. The service life of the anvil in high-pressure synthesis was increased by 1 time.

[0057] Example 2

[0058] (1) Raw material workpiece: WC-Co cemented carbide anvil (Co content 6wt%, size 51.2mm×51.2mm×51.2mm, residual stress value after high pressure synthesis is about -1181.9MPa).

[0059] (2) Equipment: Intelligent vibration aging instrument, current-controlled heating system.

[0060] (3) The processing procedure is as follows:

[0061] S1 Pretreatment: The surface of the anvil is cleaned with alcohol to remove oil stains; a rigid clamp is used to clamp the anvil and the vibration table so that they can make rigid contact; a temperature sensor is installed on the surface of the anvil; a high-frequency induction coil is wrapped around the vibration table; and a vibration pickup, i.e., a vibration sensor, is installed.

[0062] S2 Current Controlled Heating: The induction heating device is activated, and the following settings and controls are implemented through the central control system: First stage: Heating to 100℃ at a rate of 2℃ / min, holding for 120min; Second stage: Adjusting the power, heating to 150℃ at a rate of 2℃ / min, holding for 240min, then heating to 190℃ at a rate of 2℃ / min, holding for 740min; Cooling process: Reducing the current power, and controlling the cooling rate to approximately 1℃ / min to 150℃ through natural cooling.

[0063] S3 Cooperative Vibration Aging: When the anvil temperature drops to 150℃, the vibration aging instrument is started. A 50-500Hz frequency sweep identifies the anvil's natural frequency as 70Hz. The excitation frequency is set to 69Hz, the amplitude to 0.3mm, the vibration acceleration to 9m / s², and the excitation time to 120min. During this period, the temperature is maintained between 140-160℃.

[0064] S4 Cooling and Post-treatment: After vibration, reduce the current power and allow the anvil to cool naturally to 50°C. o C. Remove the clamps, coils / electrodes, and sensors; clean the surfaces. Place the anvil at a temperature of 50°C. o Store in a constant temperature room (C).

[0065] (4) Performance testing:

[0066] The residual stress was measured by X-ray diffraction. The results showed that the average residual stress of the anvil was reduced to 791.16 MPa, with an elimination rate of 33.01%. The hardness test (HRA) was 89.4, which was basically consistent with that before treatment. The anvil had a service life of 4 cycles in high-pressure synthesis.

[0067] Example 3

[0068] (1) Raw material workpiece: WC-Co cemented carbide anvil (Co content 6wt%, size 51.2mm×51.2mm×51.2mm, residual stress value after high pressure synthesis is about 1201.9MPa).

[0069] (2) Equipment: Intelligent vibration aging instrument, current-controlled heating system.

[0070] (3) The processing procedure is as follows:

[0071] S1 Pretreatment: The surface of the anvil is cleaned with alcohol to remove oil stains; a rigid clamp is used to clamp the anvil and the vibration table so that they can make rigid contact; a temperature sensor is installed on the surface of the anvil; a high-frequency induction coil is wrapped around the vibration table; and a vibration pickup, i.e., a vibration sensor, is installed.

[0072] S2 Current Controlled Heating: The induction heating device is started, and the following settings and controls are made through the central control system: First stage: the temperature is increased to 100℃ at a rate of 2℃ / min and held for 120min; Second stage: the power is adjusted, the temperature is increased to 150℃ at a rate of 1℃ / min and held for 240min, and then increased to 190℃ at a rate of 2℃ / min and held for 1440min; Cooling process: the current power is reduced, and the temperature is controlled to drop to 100℃ at a rate of approximately 1℃ / min through natural cooling.

[0073] S3 Cooperative Vibration Aging: When the anvil temperature drops to 100℃, the vibration aging instrument is started. A 50-500Hz frequency sweep identifies the anvil's natural frequency as 76Hz. The excitation frequency is set to 74Hz, the amplitude to 0.3mm, the vibration acceleration to 5m / s², and the excitation time to 120min. During this period, the temperature is maintained between 140-160℃.

[0074] S4 Cooling and Post-treatment: After vibration, reduce the current power and allow the anvil to cool naturally to 50°C. o C. Remove the clamps, coils / electrodes, and sensors; clean the surfaces. Place the anvil at a temperature of 50°C. o Store in a constant temperature room (C).

[0075] (4) Performance testing: The residual stress was measured by X-ray diffraction. The results showed that the average residual stress of the anvil was reduced to 802.97, and the removal rate was 33.2%; the hardness test (HRA) was 89.7, which was basically consistent with that before treatment; the service life of the anvil in high pressure synthesis reached 5 times.

[0076] Comparative Example 1

[0077] Single vibration aging:

[0078] (1) Raw material workpiece: WC-Co cemented carbide anvil, the same as in Example 1;

[0079] (2) Process: Only the S2 vibration aging step in Example 1 is performed (excitation frequency 68Hz, amplitude 0.3mm, time 90min).

[0080] (3) Performance test: The residual stress decreased from 1292 to 1128 MPa, with an elimination rate of only 12.6%; the service life of the anvil did not improve.

[0081] Comparative Example 2

[0082] Using a single thermal aging process:

[0083] (1) Raw material workpiece: WC-Co cemented carbide anvil, the same as in Example 1;

[0084] (2) Process: Only perform the S3 heat treatment step in Example 1 (hold at 170℃ for 740 min, then slowly cool down);

[0085] (3) Performance test: The residual stress decreased from 1015.5 MPa to 783.5 MPa, with an elimination rate of 22.8%; one of the anvils developed a crack during the use of the entire set of anvils.

[0086] Comparative Example 3

[0087] Using a single thermal aging process:

[0088] (1) Raw material workpiece: WC-Co cemented carbide anvil, the same as in Example 1;

[0089] (2) Process: Only perform the S3 heat treatment step in Example 1 (hold at 300℃ for 360 min, then slowly cool down);

[0090] (3) Performance testing: The heat preservation stage before the anvil performance testing, that is, at 300°C o When the heat treatment temperature is high, the stress distribution inside the anvil is uneven, leading to the frying of the pieces.

[0091] The following table compares the performance test results of the examples and comparative examples:

[0092] Table 1

[0093]

[0094] As can be seen from the above examples and comparative examples, the present invention employs a synergistic process of "step heating (to 190℃) + 150℃ hot vibration" for WC-Co cemented carbide anvils. The result is a residual stress relief rate of 25.3%, while simultaneously maintaining the hardness (HRA 89.5) and doubling the high-pressure service life. This demonstrates the superior comprehensive effectiveness of the present invention in deeply relieving stress and protecting material properties. Comparative Example 1 only underwent room temperature vibration aging. Although there was no damage during the anvil pressing process, the residual stress relief rate was only 12.6% (see Table 1), and the service life was not improved. This indicates that for high-hardness materials like cemented carbide, single vibration aging is insufficient to effectively relax the deep residual stress within. Comparative Example 2 only underwent long-term heat treatment at 170℃. The residual stress relief rate was 22.8% (see Table 1). Although the relief rate was not very low, cracking of the anvil occurred in actual use, such as... Figure 2 As shown. This illustrates that simple low-temperature heat treatment has limited stress relief capabilities, and most importantly, it cannot homogenize stress, leaving stress concentration points that lead to service failure. Comparative Example 3 increased the heat treatment temperature to 300℃. As a result, the anvil directly "exploded" during the heat treatment process, as shown. Figure 3As shown, this starkly demonstrates that for cemented carbide anvils with pre-existing high residual stress, applying high heat treatment temperatures can easily lead to catastrophic instantaneous fracture due to the complex interaction between thermal stress and residual stress, posing an extremely high risk.

[0095] In summary, the comparative results fully demonstrate that the "thermal-vibration synergy" method of this invention is not a simple superposition of thermal and vibrational effects, but rather a synergistic qualitative change of "1+1>2" generated under a specific low-temperature time window. It successfully solves the industry problems of "insufficient effect" of single vibration aging, "insufficient effectiveness" of single low-temperature thermal aging, and "excessive risk" of single high-temperature thermal aging. Under the premise of ensuring that the core performance of the cemented carbide anvil is not damaged, it achieves efficient, uniform, and safe elimination of residual stress.

[0096] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some or all of the technical features thereof, within the spirit and principles of the present invention, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for eliminating residual stress in a thermally vibrating cemented carbide anvil, characterized in that, include: The cemented carbide anvil is subjected to heat treatment; during the cooling process of the heat treatment, when the temperature of the cemented carbide anvil drops to the range of 150°C to 200°C, vibration aging treatment is applied to the cemented carbide anvil.

2. The method for eliminating residual stress in a thermally vibrating cemented carbide anvil according to claim 1, characterized in that, The heat treatment includes a stepped heating process: (1) Heat the cemented carbide anvil to a first temperature T1 and keep it at that temperature; (2) The cemented carbide anvil processed in step (1) is further heated to a second temperature T2 and kept at that temperature, wherein T2 is higher than T1 but not higher than 200°C; (3) Begin the cooling process.

3. The method for eliminating residual stress in a thermally induced shock-induced cemented carbide anvil according to claim 2, characterized in that, Step (1) The first temperature T1 is 90-110℃ and the holding time is 60-90 minutes; Step (2) The second temperature T2 is 150-190℃ and the holding time is 700-750 minutes.

4. The method for eliminating residual stress in a thermally vibrating cemented carbide anvil according to claim 3, characterized in that, The rate of heating from room temperature to T1 is controlled at 3-5℃ / min; the rate of heating from T1 to T2 is controlled at 2-3℃ / min.

5. The method for eliminating residual stress in a thermally vibrating cemented carbide anvil according to any one of claims 2 to 4, characterized in that, The cooling rate of the cooling process in step (3) is controlled at 1-2℃ / min.

6. The method for eliminating residual stress in a thermally vibrating cemented carbide anvil according to any one of claims 1 to 4, characterized in that, Before performing the vibration aging treatment, the natural frequency of the cemented carbide anvil is first identified by frequency sweep, and the excitation frequency is set based on the natural frequency; the excitation frequency is set within ±5Hz of the natural frequency, and the vibration amplitude is 0.1-0.5mm.

7. The method for eliminating residual stress in a thermally vibrating cemented carbide anvil according to claim 6, characterized in that, During the vibration aging treatment, the temperature of the cemented carbide anvil is maintained between 140°C and 200°C by controlling heating or cooling.

8. The method for eliminating residual stress in a thermally vibrating cemented carbide anvil according to claim 7, characterized in that, The duration of the vibration aging treatment is 60-120 minutes.

9. An apparatus for use in the thermally induced stress relief method for residual stress in a cemented carbide anvil as described in any one of claims 1 to 8, characterized in that, It includes a vibration table, an electric heating device (1) surrounding the vibration table, a sample (4) placed on the vibration table and pressed by a pressure iron (3), an exciter (7) and a pickup (8) placed on the vibration table, and a temperature sensor (5) on the sample (4); a rubber pad (2) is provided at the bottom of the vibration table.

10. The device for eliminating residual stress in the thermally induced shock-induced cemented carbide anvil stress elimination method according to claim 9, characterized in that, It also includes a central control system (9), which is electrically connected to an electric heating device (1), an exciter (7), a vibration pickup (8), and a temperature sensor (5).

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