Hydrogen induced cracking acoustic testing system and method

Abstract

The application discloses a hydrogen-induced cracking acoustic testing system and method, which comprises an electrochemical environment simulation device, a stress loading device, a temperature loading device, an acoustic emission testing device and a control device. The electrochemical environment simulation device is internally provided with a test piece and is used for providing a corrosion environment required by hydrogen-induced cracking testing. The stress loading device and the temperature loading device are used for providing specified load force and temperature required by testing. The acoustic emission testing device is used for recording acoustic emission signals generated after starting hydrogen-induced cracking testing under the conditions of the specified load force and the temperature. The control device is used for starting the electrochemical environment simulation device and the acoustic emission testing device when the stress loading device and the temperature loading device respectively reach the corresponding specified load force and temperature, and receiving the acoustic emission signals, so as to analyze the evolution law of hydrogen-induced cracking of the test piece material. The application truly simulates the working condition of the hydrogen-induced cracking process of the test piece material, studies the hydrogen-induced cracking performance of the material, and improves the accuracy and reliability of the experimental results.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material performance research, in particular to a hydrogen induced cracking acoustic testing system and method. BACKGROUND

[0002] Hydrogen induced cracking is a common failure mode of in-service pressure vessels. Since pressure vessels are often operated under harsh conditions such as high temperature, high pressure and strong corrosion, their medium is often flammable, explosive or corrosive and toxic. Once leakage or explosion occurs, it will directly affect people's life and property safety, national economic safety operation and social stability. Therefore, it is an important topic to study the damage evolution, failure mechanism and online monitoring technology of hydrogen induced cracking of materials.

[0003] The main reason for hydrogen induced cracking of materials is that hydrogen is produced by the corrosion reaction of hydrogen sulfide with the surface of steel, and the hydrogen is absorbed by the steel, leading to cracking of the steel. Therefore, the existing experiments for measuring the hydrogen induced cracking resistance of materials are generally carried out in a fume hood according to the schematic diagram in NACE TM0284 and GB / T 8650 standards, and the experimenters need to wear a gas mask for a long time. The experimental process is complex.

[0004] The damage evolution of hydrogen induced cracking is a very complex process, and a large amount of acoustic signals will be generated during this process. Acoustic emission technology can detect the occurrence and development of material corrosion and cracks by monitoring the elastic waves generated by energy release in the material, and can effectively characterize the damage evolution information in the material. It is an effective means to study the damage evolution and failure mechanism of hydrogen induced cracking. Therefore, how to accurately simulate the hydrogen induced cracking damage process of pressure vessels under laboratory conditions, and use acoustic emission technology to monitor the hydrogen induced cracking process of materials to complete the operation of collecting acoustic emission signals and extracting characteristic parameters, has very important theoretical and engineering significance for online monitoring of hydrogen induced cracking of pressure vessels.

[0005] Therefore, in the process of implementing the present application, the inventors found that there is a lack of an experimental device that can simulate the hydrogen induced cracking process of materials and obtain acoustic emission signals in the prior art. Since the existing hydrogen induced cracking experiments under laboratory conditions are carried out at room temperature, and the hydrogen induced cracking experiments based on electrochemical hydrogen charging do not have real-time detection of hydrogen concentration, and the dynamic load force loading form has a great influence on the acoustic emission signals, a large amount of noise is easily generated. Therefore, in view of the above shortcomings, the prior art urgently needs to provide an experimental device that can solve one or several of the above problems, so as to more effectively simulate the hydrogen induced cracking process of materials under actual working conditions, and effectively obtain the acoustic emission signals of the process. SUMMARY

[0006] In order to solve the above technical problems, the application provides a hydrogen-induced cracking acoustic testing system, which comprises: an electrochemical environment simulation device, which is internally provided with a test piece and is used for providing a corrosion environment required by hydrogen-induced cracking testing; a stress loading device and a temperature loading device, which are used for providing specified load force and temperature required by testing; an acoustic emission testing device, which is used for recording acoustic emission signals generated after starting hydrogen-induced cracking testing under the condition of the specified load force and temperature; and a control device, which is used for starting the electrochemical environment simulation device and the acoustic emission testing device when the stress loading device and the temperature loading device respectively reach the specified load force and temperature, and receiving the acoustic emission signals, so as to analyze the evolution law of hydrogen-induced cracking of the test piece material.

[0007] Preferably, the electrochemical environment simulation device comprises: an environment box, which is internally provided with a first cavity and a second cavity which are spaced apart from each other, the first cavity is used for accommodating the test piece and hydrogen-charged electrolyte required by current testing, and the second cavity is used for containing water bath solution used for transferring heat to the first cavity; an auxiliary electrode, which is arranged in the first cavity; and an electrochemical workstation, which is connected with the auxiliary electrode and the test piece, and is used for providing the test piece with a hydrogen-charged environment required by testing by outputting different currents when the auxiliary electrode and the test piece respectively serve as cathode and anode of electrochemical reaction.

[0008] Preferably, the environment box comprises: a double-layer nested sidewall, which has a cylindrical inner sidewall and a cylindrical outer sidewall with different radius lengths, the inner sidewall forms the first cavity, and the interlayer between the inner sidewall and the outer sidewall forms the second cavity; a box cover, which is connected with the double-layer nested sidewall through positioning screws; and a base, which is fixedly connected with the double-layer nested sidewall.

[0009] Preferably, the temperature loading device comprises: a temperature sensor, which is installed in the second cavity; a heating element, which is arranged in the second cavity, and is arranged on the annular intersection surface between the second cavity and the base; and a temperature control assembly, which is integrated in the control device, and is used for controlling the heating element to heat the water bath solution, and monitoring the internal temperature of the water bath solution in real time and diagnosing whether the current temperature reaches the specified temperature.

[0010] Preferably, the middle section of the test piece is configured as a cylindrical structure, two ends of the middle section are formed as a first end body and a second end body, and the first end body and the second end body are both configured as rectangular column structures, wherein the diameter of the middle section is greater than the diagonal line of the end face of the rectangular column end body.

[0011] Preferably, the stress loading device comprises: a first tensile clamp and a second tensile clamp fixedly connected with the first end body and the second end body respectively, wherein the middle section of the test piece penetrates through the central axis of the environmental box in the electrochemical environment simulation device; and a tensile testing machine connected with the first tensile clamp and the second tensile clamp.

[0012] Preferably, the acoustic emission testing device comprises: a first acoustic emission sensor and a second acoustic emission sensor arranged on the first end body and the second end body respectively; and an acoustic emission instrument electrically connected with the first acoustic emission sensor and the second acoustic emission sensor, used for acquiring acoustic emission signals of each channel and forwarding the acoustic emission signals to the control device after analog-digital conversion.

[0013] Preferably, the system further comprises: a hydrogen detection device arranged in the first cavity, used for monitoring the hydrogen concentration in the cavity in real time during testing.

[0014] Preferably, the control device is further used for starting and stopping control of the hydrogen charging operation in the system, wherein when the test piece reaches the hydrogen-induced cracking state, the stress loading device, the temperature loading device, the electrochemical environment simulation device and the acoustic emission testing device are controlled to stop working to stop the hydrogen charging.

[0015] In another aspect, the present application also provides a hydrogen-induced cracking acoustic testing method, which is implemented by using the system as described above, and the method comprises the following steps: installing the electrochemical environment simulation device, the stress loading device and the temperature loading device required for current testing, so as to construct a corrosion environment, a specified load and a temperature control environment required for hydrogen-induced cracking testing; when the control device controls the stress loading device and the temperature loading device to reach the specified load and the temperature respectively, the control device controls the electrochemical environment simulation device and the acoustic emission testing device to start; the acoustic emission testing device records the acoustic emission signals generated in real time; and the control device receives the acoustic emission signals and analyzes the evolution law of hydrogen-induced cracking of the test piece material.

[0016] Compared with the prior art, one or more embodiments in the above solution can have the following advantages or beneficial effects:

[0017] The application provides a hydrogen-induced cracking acoustic testing system and method. The system and method provide a safe and reliable hydrogen charging environment by using an environmental box; hydrogen-induced cracking experiments under a constant load and a constant temperature hydrogen charging environment are synchronously completed; meanwhile, by setting a heating base, a temperature sensor and a temperature control component, a stable hydrogen charging environment can be realized, and relevant parameters of the hydrogen charging environment can be controllably adjusted according to design requirements, so that the working condition of the hydrogen-induced cracking process of a pressure container can be more truly simulated, and the accuracy and reliability of experimental results are improved. In this way, the application can observe the bubbles, the corrosion of the surface of a test piece and the generation and development of cracks in the experimental process at any time under the condition of ensuring the safety of the experiment, researches the hydrogen-induced cracking performance of a material according to acoustic data of the hydrogen-induced cracking process obtained by using acoustic emission technology, deeply explores the evolution law of the hydrogen-induced cracking of a test piece material, and provides a basis for online monitoring of the hydrogen-induced cracking of equipment in an actual production process.

[0018] Other features and advantages of the present application will be set forth in the following description, and in part will be apparent from the description, or can be learned by practice of the present application. The objects and other advantages of the present application will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification, illustrate embodiments of the present application and together with the description serve to explain the present application, but are not intended to limit the present application. In the drawings:

[0020] Figure 1 It is a whole block diagram of the hydrogen-induced cracking acoustic testing system of the embodiment of the present application.

[0021] Figure 2 It is a specific structure diagram of the hydrogen-induced cracking acoustic testing system of the embodiment of the present application.

[0022] Figure 3 It is a structure schematic diagram of the environmental box in the hydrogen-induced cracking acoustic testing system of the embodiment of the present application.

[0023] Figure 4 It is a structure schematic diagram of the test piece in the hydrogen-induced cracking acoustic testing system of the embodiment of the present application.

[0024] Figure 5 It is a step diagram of the hydrogen-induced cracking acoustic testing method of the embodiment of the present application. DETAILED DESCRIPTION

[0025] The embodiments of the present application will be described in detail below with reference to the accompanying drawings and embodiments, so that how the present application applies technical means to solve technical problems and achieves technical effects can be fully understood and implemented. It should be noted that, as long as there is no conflict, each embodiment in the present application and each feature in each embodiment can be combined with each other, and the technical solutions formed thereby are all within the protection scope of the present application.

[0026] In addition, the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Moreover, although a logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown.

[0027] Hydrogen-induced cracking is a common failure mode of in-service pressure vessels. Since pressure vessels are often operated under harsh conditions such as high temperature, high pressure and strong corrosion, the medium is often flammable, explosive or corrosive and toxic. Once leakage or explosion occurs, it will directly affect the safety of people's life and property, the safe operation of national economy and social stability. Therefore, it is an important topic to study the damage evolution, failure mechanism and online monitoring technology of hydrogen-induced cracking of materials.

[0028] The main reason for hydrogen-induced cracking of materials is that hydrogen is produced by the corrosion reaction of hydrogen sulfide with the surface of steel, and the hydrogen is absorbed by the steel, resulting in cracking of the steel. Therefore, the existing experiments for measuring the hydrogen-induced cracking resistance of materials are generally carried out in a fume hood according to the schematic diagram in NACE TM0284 and GB / T 8650 standards. The experimenter needs to wear a gas mask for a long time, and the experimental process is complex.

[0029] The damage evolution of hydrogen-induced cracking is a very complex process, and a large amount of acoustic signals will be generated during this process. Acoustic emission technology can detect the occurrence and development of material corrosion and cracking by monitoring the elastic waves generated by energy release inside the material, and can effectively characterize the damage evolution information inside the material. It is an effective means to study the damage evolution and failure mechanism of hydrogen-induced cracking. Therefore, how to accurately simulate the hydrogen-induced cracking damage process of pressure vessels under laboratory conditions and use acoustic emission technology to monitor the hydrogen-induced cracking process of materials to complete the operation of collecting acoustic emission signals and extracting characteristic parameters has very important theoretical and engineering significance for online monitoring of hydrogen-induced cracking of pressure vessels.

[0030] Therefore, in the process of realizing the present application, the inventors find that the prior art lacks an experimental device that can more closely simulate the hydrogen-induced cracking process of materials and obtain acoustic emission signals. Since existing hydrogen-induced cracking experiments in laboratory conditions are carried out at room temperature, and the hydrogen-induced cracking experiment based on electrochemical hydrogen charging does not detect the hydrogen concentration in real time, and the dynamic load force loading form has a greater impact on the acoustic emission signal, it is easy to produce a large amount of noise. Therefore, in view of the above shortcomings, the prior art urgently needs to provide an experimental device that can solve one or several of the above problems, so as to more effectively simulate the hydrogen-induced cracking process of materials under actual working conditions, and effectively obtain the acoustic emission signals of the process.

[0031] In order to solve the above technical problems, the present application provides a hydrogen-induced cracking acoustic testing system and method. The system and method at least include: an electrochemical environment simulation device, a stress loading device, a temperature loading device, an acoustic emission testing device and a control device. The system simulates the electrochemical corrosion environment of the test specimen material in the hydrogen-induced cracking formation process through the electrochemical environment simulation device; simulates the specified load force and specified temperature required to maintain the test specimen material in the hydrogen-induced cracking process through the stress loading device and the temperature loading device; collects the acoustic emission signals generated in the hydrogen-induced cracking process through the acoustic emission testing device; finally, through the control device, analyzes the evolution law of the hydrogen-induced cracking of the test specimen material according to the received acoustic emission signals. In this way, the present application can provide a hydrogen-induced cracking acoustic testing system under a constant load and temperature-controlled hydrogen charging environment, which can controllably adjust the environmental temperature and load force in the hydrogen charging environment, can more realistically simulate the working conditions required for the hydrogen-induced cracking process of the test specimen material, and improves the accuracy and reliability of the experimental results.

[0032] In addition, the testing system described in the present application further includes a hydrogen detection device for dynamically monitoring the concentration parameters of hydrogen in the electrochemical corrosion environment. Therefore, the present application can more deeply and accurately explore the evolution law of the hydrogen-induced cracking of the test specimen material.

[0033] Example One

[0034] Figure 1 The overall block diagram of the hydrogen-induced cracking acoustic testing system of the embodiments of the present application is shown in FIG. 1. As shown in FIG. 1, the hydrogen-induced cracking acoustic testing system described in the present application at least includes an electrochemical environment simulation device A, a stress loading device B, a temperature loading device C, an acoustic emission testing device D and a control device F. Figure 1

[0035] ​Specifically, the electrochemical environment simulation device A is internally provided with the test sample 4. The electrochemical environment simulation device A is used to provide the electrochemical corrosion environment required by the hydrogen-induced cracking test, so as to ensure that the pitting corrosion pits in the test sample material (the material to be tested) have a certain corrosion intensity, so as to simulate the corrosion environment in which the test sample material is actually used. The stress loading device B is used to provide the specified load force required by the current hydrogen-induced cracking test to the test sample 4, so as to simulate the stress energy to which the test sample material is subjected in actual use. The temperature loading device C is used to provide the specified temperature required by the current hydrogen-induced cracking test to the test sample 4, so as to simulate the temperature environment to which the test sample material is subjected in actual use. In actual application, due to the stress acting on the test sample material, the test sample macroscopically exhibits a certain strength to resist the actual environmental conditions in which the test sample is located, so that the embodiment of the present application first simulates the stress environment in which the test sample material is located by using the stress loading device B, and then needs to simulate the temperature environment in which the test sample material is located by using the temperature loading device C.

[0036] Further, the control device F is connected with the electrochemical environment simulation device A, the stress loading device B and the temperature loading device C respectively. On the one hand, the control device F can control the start and stop of the electrochemical environment simulation device A to control the start and stop of the hydrogen charging operation required by the test, control the start and stop of the stress loading device B to control the start and stop of the stress environment required by the test, and control the start and stop of the temperature loading device C to control the start and stop of the temperature environment required by the test. At the same time, the control device F is also used to send the corresponding corrosion intensity parameter, the specified load force parameter and the specified temperature parameter to the electrochemical environment simulation device A, the stress loading device B and the temperature loading device C respectively according to the design parameters of the current hydrogen-induced cracking test, so that the electrochemical environment simulation device A, the stress loading device B and the temperature loading device C respectively control the output performance parameters of themselves according to the obtained parameters. In this way, the embodiment of the present application can control the corrosion intensity, the load force and the environmental temperature required by the current hydrogen-induced cracking test by using the control device F.

[0037] Therefore, the electrochemical environment simulation device A, the stress loading device B and the temperature loading device C are used to provide the related devices for simulating the actual environmental state (corrosion condition, constant load force and controllable temperature condition) applied to the test sample for the current test, so as to complete the construction of the test sample material application environment required by the current hydrogen-induced cracking test.

[0038] Further, the acoustic emission testing device D is used to record the acoustic emission signals generated by the test piece material during the hydrogen-induced cracking process after starting the hydrogen-induced cracking test under the conditions of the specified load force and the specified temperature. In this way, the acoustic emission testing device D can obtain the acoustic emission signals generated by the test piece at different times in real time during the hydrogen-induced cracking test implementation process, to characterize the acoustic feature change state of the test piece during the entire hydrogen-induced cracking evolution process.

[0039] Further, in the embodiment of the present application, the control device F can be used to control the start and stop states of the electrochemical environment simulation device A, the stress loading device B, the temperature loading device C and the acoustic emission testing device D respectively. Further, the control device F is used to start the electrochemical environment simulation device A and the acoustic emission testing device D when the stress loading device B and the temperature loading device C reach the corresponding specified load force and specified temperature respectively, and receive the acoustic emission signals generated by the test piece at different times after starting the hydrogen-induced cracking test, so as to analyze the evolution law of the hydrogen-induced cracking of the test piece material according to the obtained acoustic emission signals.

[0040] Therefore, the hydrogen-induced cracking acoustic testing system of the present application can simulate the working conditions of the test piece material in the actual application environment through the controllable adjustment of the corrosion intensity, the specified size control of the load force, and the controllable adjustment state of the temperature condition, so as to study the hydrogen-induced cracking performance of the test piece material through the control device according to the acoustic emission signals collected by the acoustic emission testing device, and explore the evolution law of the hydrogen-induced cracking.

[0041] Example Two

[0042] Figure 2 The specific structure diagram of the hydrogen-induced cracking acoustic testing system of the embodiment of the present application. Based on the above embodiment one, the specific structure and function of each device in the hydrogen-induced cracking acoustic testing system of the embodiment of the present application will be described below. Figure 1 and Figure 2 The specific structure and function of each device in the hydrogen-induced cracking acoustic testing system of the embodiment of the present application will be described.

[0043] Reference Figure 2 In the embodiment of the present application, the electrochemical environment simulation device A includes but is not limited to: an environment box 11, an auxiliary electrode 5 and an electrochemical workstation (not shown). The electrochemical workstation is connected to the control device F, and the electrochemical workstation is controlled by the control device F to start and stop, and is configured with a corresponding corrosion intensity parameter, so that the electrochemical workstation outputs an output current matched with the current corrosion intensity data after obtaining the corrosion intensity parameter, so as to form a corresponding potential difference between the auxiliary electrode and the reference electrode.

[0044] Further, in the embodiment of the present application, the environment box 11 adopts a corrosion-resistant organic glass environment box. Figure 3This is a schematic diagram of the environmental chamber in the hydrogen-induced cracking acoustic testing system according to an embodiment of this application. (Reference) Figure 3 The environmental chamber 11 has a first chamber and a second chamber spaced apart from each other. The first chamber contains the specimen 4 and the hydrogen-filled electrolyte required for the current hydrogen-induced cracking test, wherein the specimen 4 is placed in the hydrogen-filled electrolyte. The second chamber contains a water bath solution used to transfer heat to the first chamber. An auxiliary electrode 5 is disposed in the first chamber. An electrochemical workstation is connected to both the auxiliary electrode 5 and the specimen 4, and is used to provide the hydrogen-filled environment required for the current hydrogen-induced cracking test to the specimen 4 by outputting currents of different amplitudes, with the auxiliary electrode 5 and the specimen 4 acting as the cathode and anode of the electrochemical reaction, respectively. Thus, this embodiment of the invention provides a corrosion environment that meets the current design requirements for the hydrogen-induced cracking test of the specimen 4 using an electrochemical environment simulation device A.

[0045] like Figure 3 As shown, the environmental enclosure 11 includes side walls, a lid 8, and a base 10. Specifically, in this embodiment of the invention, the side walls adopt a double-layer nested structure, consisting of cylindrical side walls of different radii. Specifically, it includes an inner cylindrical side wall with a first radius and an outer cylindrical side wall with a second radius, the first radius being smaller than the second radius. A first cavity is formed inside the inner cylindrical side wall, and a second cavity is formed between the inner and outer cylindrical side walls. The first end of the double-layer nested side wall is the lid 8, which is connected to the double-layer nested side wall via a positioning screw. The base 10 is fixedly connected to the double-layer nested side wall. The double-layer nested side wall is made of transparent, corrosion-resistant organic glass, and both the base 10 and the lid 8 are made of corrosion-resistant materials.

[0046] Furthermore, in this embodiment of the invention, the environmental chamber 11 is divided into two layers (i.e., the inner layer is the first cavity, and the outer layer is the second cavity with a ring-shaped cylindrical structure) by a cylindrical inner wall. The second cavity contains an aqueous solution, so that the outer layer of the current corrosion-resistant acrylic environmental chamber 11 provides a water bath heating environment for the inner layer. The first cavity contains an electrochemical hydrogen-charging electrolyte. The electrochemical hydrogen-charging electrolyte is preferably a uniform mixture of 2% sulfuric acid, 0.05% acetic acid, 0.005% propylene thiourea, 0.5% sodium chloride, and 96.695% distilled water.

[0047] Furthermore, in this embodiment of the invention, the temperature loading device C includes, but is not limited to: a temperature sensor 6, a heating element (not shown), and a temperature control component (not shown). Reference Figure 3The base 10 is provided with a heating element. Specifically, the center of the base 10 has a circular table protruding into the interior of the environmental box 11, and an annular heating element (not shown) is arranged at the outer circle of the circular table. The heating element is arranged on the annular intersection surface between the second cavity and the base 10, and the cross-sectional shape of the annular heating element matches the annular intersection surface. The heating element is used to heat the water bath solution in the second cavity under the control of the temperature control assembly, so that the hydrogen-filled environment in the first cavity obtains corresponding heat in the form of water bath heating. The temperature sensor 6 is arranged in the above-mentioned second cavity to detect the temperature of the water bath solution in the second cavity in real time. The temperature control assembly is integrated in the control device F and is connected with the heating element and the temperature sensor 6 respectively. On the one hand, the temperature control assembly is used to obtain a specified temperature parameter and output a heating control signal matched with the current specified temperature parameter, so as to transmit the current heating control signal to the heating element to control the heating element to heat the water bath solution according to the specified temperature. On the other hand, the temperature control assembly is also used to obtain internal temperature data of the water bath solution monitored in real time from the temperature sensor 6 and diagnose whether the current temperature data reaches the specified temperature. If the temperature control assembly judges that the current feedback temperature does not reach or exceeds the specified temperature, a new heating control signal is generated and sent to the heating element until the temperature of the water bath solution reaches the current required specified temperature.

[0048] In this way, the embodiment of the present application realizes the temperature control effect of the hydrogen-induced cracking test by using the above-mentioned temperature loading device C, so that the electrolysis environment temperature can be monitored and adjusted in real time according to the feedback temperature returned by the temperature sensor, so as to simulate the controllable temperature environment of the current hydrogen-induced cracking test.

[0049] Figure 4 FIG. 1 is a structural schematic diagram of a hydrogen-induced cracking acoustic test system according to an embodiment of the present application. As shown in FIG. 1, the hydrogen-induced cracking acoustic test system includes an environmental box 11, a test piece 4, a temperature loading device C, a temperature sensor 6, a control device F, and a data processing device D. Figure 4 As shown in FIG. 1, in the embodiment of the present application, the test piece 4 is configured as a middle section, a first end body and a second end body. Specifically, the middle section of the test piece 4 is configured as a cylindrical structure, and the two ends of the middle section are formed into the first end body and the second end body respectively. The first end body and the second end body are both configured as rectangular column structures, and the diameter of the middle section is greater than the diagonal of the end face of the rectangular column end body. In actual application, first, the length of the middle section of the test piece 4 is greater than the overall height of the environmental box 11 composed of the box cover 8, the side wall and the base 10. Second, a hydrogen-filled part is polished on the surface of a preset length section in the middle section of the test piece 4, and the surface of the remaining area of the middle section is sealed with epoxy resin. Finally, a corresponding sensor mounting area is polished on the surface of the first end body and the second end body of the test piece 4 respectively, which are used to mount the acoustic emission sensors 14 described below.

[0050] When installing specimen 4, its middle section needs to pass through the central axis of the environmental chamber 11. Specifically, a first through-hole adapted to the cross-section of the middle section is provided at the center of the cover 8 of the environmental chamber 11, and a second through-hole adapted to the cross-section of the middle section is provided at the center of the base 10 of the environmental chamber 11, thus allowing the middle section of specimen 4 to pass through the central axis of the environmental chamber 11. Furthermore, when installing specimen 4, a certain distance needs to be reserved at both ends of the middle section, ensuring that the end face of the first end near the middle section is a certain distance from the environmental chamber 11, and also ensuring that the end face of the second end near the middle section is a certain distance from the environmental chamber 11. For example, the length of the middle section of specimen 4 is 10cm higher than the overall height of the environmental chamber. Except for the first and second end bodies of the middle section which are rectangular structures, the surface of the middle section of the specimen is ground to form a hydrogen filling area. The remaining area is sealed with epoxy resin and fixed to the environmental chamber. The first and second end bodies are ground to form sensor installation areas to provide a place for the acoustic emission sensor.

[0051] Furthermore, in this embodiment of the invention, the stress loading device B includes, but is not limited to: a first tensile clamp 2, a second tensile clamp 3, and a tensile testing machine 1. For example... Figure 2 As shown, the tensile testing machine 1 is connected to the first tensile clamp 2 and the second tensile clamp 3. The first tensile clamp 2 is fixedly connected to the first end body, and the second tensile clamp 3 is fixedly connected to the second end body. Additionally, the control device F is connected to the tensile testing machine 1. At this time, the control device F is used to control the start-up and shutdown status of the tensile testing machine 1, and to generate a tensile control signal matching the currently specified load force parameter based on the acquired specified load force parameter. This tensile control signal is then sent to the tensile testing machine 1, enabling the tensile testing machine to drive the two clamps 2 to apply an external load force to the specimen 4 according to the specified load force, thereby simulating the load force environment of the current hydrogen-induced cracking test.

[0052] Further, in the embodiment of the present application, the acoustic emission testing device D includes but is not limited to: a first acoustic emission sensor 12, a second acoustic emission sensor 12, and an acoustic emission instrument 14. Among them, the first acoustic emission sensor 12 is arranged on the surface of the first end body, and the second acoustic emission sensor 12 is arranged on the surface of the second end body. Further, the first acoustic emission sensor 12 is arranged in the sensor mounting area of the first end body, and the second acoustic emission sensor 12 is arranged in the sensor mounting area of the second end body. The acoustic emission instrument 14 adopts a PCI-2 full-digital acoustic emission instrument, and the acoustic emission instrument 14 is electrically connected with the first acoustic emission sensor 12 and the second acoustic emission sensor 12 through the lead wire 13. The acoustic emission instrument 14 is used to acquire the acoustic emission signals detected by each channel in real time, and after the acoustic emission signals are analog-digital converted, the acoustic emission signals are forwarded to the control device F. At this time, the control device F is used to receive the acoustic emission data in the current hydrogen induced cracking test process, and analyze the law of the evolution process of the hydrogen induced cracking of the test piece material according to the acoustic emission data.

[0053] In addition, with reference to Figure 1 and Figure 2 , the hydrogen induced cracking acoustic testing system provided by the present application further includes: a hydrogen detection device E. Among them, the hydrogen detection device E is arranged in the first cavity. The device E is used to detect and monitor the hydrogen concentration in the first cavity in real time during the current hydrogen induced cracking test process. Further, the control device F is connected with the hydrogen detection device E. The control device F is used to acquire the hydrogen concentration data detected in real time from the hydrogen detection device E, so as to assist in analyzing the law of the evolution process of the hydrogen induced cracking of the test piece material, and provide more data analysis basis for the research on the hydrogen induced cracking characteristics of the test piece material.

[0054] Further, in the embodiment of the present application, the first through hole for mounting the auxiliary electrode 5, the second through hole for mounting the temperature sensor 6, and the third through hole for mounting the hydrogen detection device E are arranged on the box cover 8. Among them, the first through hole is the mounting hole of the auxiliary electrode 5, when the auxiliary electrode 5 is mounted, the auxiliary electrode 5 is inserted into the first through hole and fixed, and the auxiliary electrode 5 is inserted into the electrochemical hydrogen charging electrolyte. The second through hole is the mounting hole of the temperature sensor 6, and the temperature sensor 6 is inserted into the second through hole and fixed. The third through hole is the mounting hole of the hydrogen detection device E, and the hydrogen detection device E is inserted into the third through hole and fixed.

[0055] In addition, in the embodiment of the present application, the control device F is also used to start and stop control of the hydrogen charging operation in the system. It should be noted that the hydrogen charging operation (i.e. the stopping time of the hydrogen-induced cracking test) is not specifically limited in the embodiment of the present application, and those skilled in the art can set it according to actual needs. It can be either continuously monitored on the acoustic characteristics of the test piece material regardless of whether the test piece has hydrogen-induced cracking phenomenon, or the test can be stopped when the test piece has hydrogen-induced cracking, or the test can be continuously monitored for a period of time after the test piece has hydrogen-induced cracking and then stopped. Preferably, after the hydrogen-induced cracking acoustic test system is started, if the test piece 4 reaches the hydrogen-induced cracking state, the control device F can also control the stress loading device B, the temperature loading device C, the electrochemical environment simulation device A and the acoustic emission testing device D to stop working, so as to stop the hydrogen charging operation and the signal acquisition operation. In this way, when the hydrogen-induced cracking of the test piece material is observed through the organic glass, the hydrogen charging is stopped at any time, and the hydrogen-induced cracking characteristics of the test piece material are analyzed in depth according to the real-time acquired hydrogen concentration data and acoustic emission data.

[0056] Example Three

[0057] Based on the hydrogen-induced cracking acoustic test system described in the above embodiment one and embodiment two, the present application further provides a hydrogen-induced cracking acoustic test method. Figure 5 The steps of the hydrogen-induced cracking acoustic test method of the embodiment of the present application are shown in the figure. As shown in the figure, Figure 5 the hydrogen-induced cracking acoustic test method described in the present application includes the following steps: step S510, installing the electrochemical environment simulation device A, the stress loading device B and the temperature loading device C required for the current test, so as to construct the corrosion environment required for the hydrogen-induced cracking test, the specified load force and the temperature control environment; step S520, controlling the control device F to control the electrochemical environment simulation device A and the acoustic emission testing device D to start when the stress loading device B and the temperature loading device C respectively reach the corresponding specified load force and specified temperature; step S530, after starting the hydrogen charging, the acoustic emission testing device D records the real-time generated acoustic emission signals; and step S540, the control device F receives the acoustic emission signals collected by the acoustic emission testing device D in real time, and analyzes the evolution law of the hydrogen-induced cracking of the test piece material according to these acoustic emission signals.

[0058] The specific implementation process of the hydrogen-induced cracking acoustic test method described in the embodiment of the present application is as follows:

[0059] 1) First, fix the corrosion-resistant organic glass environment box 11 in the tensile testing machine 1, then pass the target test piece material 4 through the corrosion-resistant organic glass environment box 11, seal it with the panzi seal 15, and connect it with the lower fixed clamp 3 of the tensile testing machine 1 to realize the fixation of the overall structure of the test piece 4;

[0060] 2) The outer layer of the corrosion-resistant organic glass environmental chamber 11 is filled with two-thirds of water as a water bath environment, and the inner layer is filled with 2% sulfuric acid, 0.05% acetic acid, 0.005% propylene thiourea, 0.5% sodium chloride and 96.695% distilled water to serve as an electrolyte, with the liquid level of the inner layer being 2-3 cm higher than the weak part 2 of the target material sample 4;

[0061] 3) The lid 8 is connected to the top of the outer wall of the box body, and is fixed with a positioning screw 7. The auxiliary electrode 5, the temperature sensor 6 and the fixed hydrogen detector 17 are fixed in the specific reserved holes of the lid 8, respectively. The auxiliary electrode 5 is connected with the electrochemical workstation, and the temperature sensor 6 is connected with the temperature control assembly. The first end body of the target material sample 4 is connected with the first tensile clamp 2 of the tensile testing machine 1. The acoustic emission sensor 12 is arranged on the surface of the first end body and the second end body of the target material sample 4 through a coupling agent, and is connected with the PCI-2 full-digital acoustic emission instrument 14 through a wire 13, so as to complete the connection of the whole system;

[0062] 4) First, start the tensile testing machine 1, and stop loading at a certain fixed load (specified load force) of the target material sample 4 in the elastic stage of the target material sample; second, start the temperature loading device, heat the inner layer electrolyte to a specified temperature by the outer layer water bath, and then control the temperature; third, start the acoustic emission instrument 14, and start the electrochemical workstation through the control device to perform the electrochemical hydrogen charging experiment on the target material sample 4. During the test, a large amount of hydrogen gas is observed on the surface of the target material sample 4 connected with the negative electrode of the electrochemical workstation, part of which enters the target material sample 4 through penetration and diffusion, so as to achieve the purpose of hydrogen charging, until the target material sample 4 is cracked due to hydrogen;

[0063] 5) According to the observation during the experiment, the load force-time curve, the collected acoustic emission data and the hydrogen concentration change data obtained during the experiment are processed to analyze the evolution law of the material of the test sample in the hydrogen-induced cracking test.

[0064] The embodiment of the present application provides a hydrogen induced cracking acoustic testing system and method. The system and method provide a safe and reliable hydrogen charging environment by using an environmental box; hydrogen induced cracking experiment operation under a constant load and a constant temperature hydrogen charging environment is synchronously completed; meanwhile, by setting a heating base, a temperature sensor and a temperature control component, a stable hydrogen charging environment and controllable adjustment of related parameters of the hydrogen charging environment according to design requirements can be realized, so that the working condition of the hydrogen induced cracking process of the pressure container can be more truly simulated, and the accuracy and reliability of the experimental results are improved. In this way, the present application can observe the bubbles, the corrosion of the surface of the test piece and the generation and development of the cracks generated in the experiment process at any time under the condition of ensuring the safety of the experiment, researches the hydrogen induced cracking performance of the material according to the acoustic data in the hydrogen induced cracking process obtained by using the acoustic emission technology, deeply explores the evolution law of the hydrogen induced cracking of the test piece material, and provides a basis for online monitoring of the hydrogen induced cracking of the equipment in the actual production process.

[0065] The above merely provides the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of the changes or replacements within the technical scope disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

[0066] It should be understood that the embodiments disclosed herein are not limited to the specific structure, processing steps or materials disclosed herein, but extend to equivalent alternatives of these features understood by those skilled in the relevant art. It should also be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to be limiting.

[0067] The phrase "one embodiment" or "an embodiment" appearing in the specification is intended to mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of the phrase "one embodiment" or "an embodiment" throughout the specification are not necessarily all referring to the same embodiment.

[0068] Although the embodiments disclosed by the present application are as above, the content described is only the embodiments adopted for the purpose of facilitating the understanding of the present application, and is not intended to limit the present application. Any person skilled in the art of the present application can make any modification and change in the implementation form and details without departing from the spirit and scope of the present application, but the patent protection scope of the present application should be subject to the scope defined by the appended claims.

Claims

1. A hydrogen induced cracking acoustic testing system, characterized by, The utility model relates to a hydrogen induced cracking test device, comprising: An electrochemical environment simulation device, which is internally provided with a test piece, for providing a corrosion environment required by a hydrogen induced cracking test; A stress loading device and a temperature loading device for providing a specified load force and temperature required by the test; An acoustic emission testing device for recording acoustic emission signals generated after starting the hydrogen induced cracking test under the conditions of the specified load force and temperature; A control device for starting the electrochemical environment simulation device and the acoustic emission testing device and receiving the acoustic emission signals when controlling the stress loading device and the temperature loading device to reach the corresponding specified load force and temperature respectively, so as to analyze the evolution law of hydrogen induced cracking of the test piece material, The middle section of the test piece is configured as a cylindrical structure, the test piece is formed with a middle section and first and second end bodies at both ends of the middle section, and the first and second end bodies are configured as rectangular column structures, wherein the diameter of the middle section is greater than the diagonal of the end face of the rectangular column end body, The length of the middle section of the test piece is greater than the overall height of the environment box in the electrochemical environment simulation device, a hydrogen charging site is polished on the surface of a preset length section in the middle section, and the surface of the remaining area of the middle section is sealed with epoxy resin, wherein a sensor mounting area is polished on the surface of each of the first and second end bodies, so as to be used for mounting an acoustic emission sensor at the corresponding position and measuring an acoustic emission signal, The center of the cover of the environment box is provided with a first test piece through hole matched with the cross section of the middle section of the test piece, and the center of the base of the environment box is provided with a second test piece through hole matched with the cross section of the middle section of the test piece, so that the middle section of the test piece can penetrate from the central axis of the environment box.

2. The system of claim 1, wherein, The electrochemical environment simulation device comprises: An environment box internally configured with a first cavity and a second cavity spaced from each other, the first cavity being used for accommodating the test piece and hydrogen charging electrolyte required by the current test, and the second cavity being used for containing water bath solution for transferring heat to the first cavity; An auxiliary electrode arranged in the first cavity; An electrochemical workstation connected with the auxiliary electrode and the test piece, used for providing a hydrogen charging environment required by the test to the test piece by outputting different currents when the auxiliary electrode and the test piece are used as cathode and anode of an electrochemical reaction respectively.

3. The system of claim 2, wherein, The environment box comprises: A double-layer nested side wall with a cylindrical inner side wall and a cylindrical outer side wall having different radius lengths, the inner side wall forming the first cavity, and the interlayer between the inner side wall and the outer side wall forming the second cavity; A cover connected with the double-layer nested side wall through a positioning screw rod; A base fixedly connected with the double-layer nested side wall.

4. The system of claim 3, wherein, The temperature loading device comprises: A temperature sensor mounted in the second cavity; A heating element arranged in the second cavity, the heating element being arranged on the annular intersection surface between the second cavity and the base; A temperature control assembly integrated in the control device is used to control the heating element to heat the water bath solution and monitor the internal temperature of the water bath solution in real time and diagnose whether the current temperature reaches the specified temperature.

5. The system of claim 1, wherein, The stress loading device comprises: A first tensile clamp and a second tensile clamp fixedly connected with the first end body and the second end body respectively; A tensile testing machine connected with the first tensile clamp and the second tensile clamp.

6. The system of claim 1 or 5, wherein, The acoustic emission testing device comprises: A first acoustic emission sensor and a second acoustic emission sensor arranged on the first end body and the second end body respectively; An acoustic emission instrument electrically connected with the first acoustic emission sensor and the second acoustic emission sensor, used to acquire acoustic emission signals of each channel and transmit the acoustic emission signals to the control device after analog-digital conversion.

7. The system of any one of claims 2-4, wherein, The system further comprises: A hydrogen detection device arranged in the first cavity, used to monitor the hydrogen concentration in the cavity in real time during testing.

8. The system according to any one of claims 1-4, wherein The control device is further used to control the start and stop of the hydrogen charging operation in the system, wherein when the test piece reaches the hydrogen-induced cracking state, the stress loading device, the temperature loading device, the electrochemical environment simulation device and the acoustic emission testing device are controlled to stop working to stop the hydrogen charging.

9. A hydrogen induced cracking acoustic testing method, characterized by, The method is implemented by using the system according to any one of claims 1-8, and the method comprises: Installing the electrochemical environment simulation device, the stress loading device and the temperature loading device required for the current test, thereby constructing the corrosion environment, the specified load force and the temperature control environment required for the hydrogen-induced cracking test; The control device controls the electrochemical environment simulation device and the acoustic emission testing device to start when the stress loading device and the temperature loading device reach the corresponding specified load force and temperature respectively; The acoustic emission testing device records the acoustic emission signals generated in real time; The control device receives the acoustic emission signals and analyzes the evolution law of hydrogen-induced cracking of the test piece material.

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