Part detection method based on load holding fatigue

Abstract

The invention relates to a part detection method and system based on load-holding fatigue, a computer readable medium, a forging method and a forge piece. The part detection method comprises the following steps: obtaining a critical dimension of an alpha-phase micro-texture, which causes load-holding fatigue failure, of a detection part of a part; if the size of the alpha-phase microstructure of the detection part is greater than the critical size, judging that the part is unqualified; and if the size of the alpha-phase microstructure of the detection part is smaller than or equal to the size of the part, judging that the part is qualified.

Description

TECHNICAL FIELD

[0001] The present application relates to a part detection method based on hold-off fatigue, a detection system, a computer readable medium, a forging method, and a forged piece. BACKGROUND

[0002] Titanium alloys are widely used to manufacture compressor disks, fan disks and their blades of aero-engine due to their high specific strength and suitability for medium-high temperature. In the 1970s, the fan disk made of near-alpha IMI685 titanium alloy of RB211 engine provided by RR company failed prematurely during service. Through the accident investigation, it was first realized that the near-alpha titanium alloy had hold-off fatigue problem, i.e. the traditional triangular wave fatigue test mode could not correctly predict the service life level under actual working conditions, and the trapezoidal wave (keeping a certain period of time under peak stress) closer to the actual flight load spectrum should be used for evaluation. The trapezoidal wave fatigue keeping a certain period of time under peak stress is called hold-off fatigue. In 1997, a Boeing 767-375ER passenger plane of Canadian International Airlines flying from Beijing to Vancouver suddenly exploded during take-off, and the accident investigation results showed that the accident was caused by hold-off fatigue failure of the 3rd to 9th stage high-pressure compressor drum made of near-alpha Ti6242 alloy. After this incident, Ti6242 alloy was also recognized as a titanium alloy material with hold-off fatigue sensitivity. In 2017, the GP7270 engine equipped on Airbus A380 passenger plane also caused a non-contained accident due to hold-off fatigue of Ti64 fan disk. Specifically, hold-off fatigue can cause the service life of the part to be significantly lower than the life predicted by the cyclic fatigue test.

[0003] For the detection scheme of the hold-off fatigue resistance of the part, for example, a large number of hold-off fatigue failure tests are performed on the part to verify whether the part meets the performance requirements of hold-off fatigue, and for the use of the user, for example, for the use of the aviation industry, the corresponding flight operation procedures are formulated to reduce the peak stress level during the operation of the part.

[0004] However, the scheme of performing a large number of hold-off fatigue failure tests on the part to verify whether the part meets the performance requirements of hold-off fatigue requires a large test cost and a long test time, and the field needs a more simplified detection method for hold-off fatigue performance. SUMMARY

[0005] One object of the present application is to provide a part detection method based on hold-off fatigue.

[0006] One object of the present application is to provide a part detection system.

[0007] One object of the present application is to provide a computer readable medium.

[0008] It is an object of the present application to provide a forging method of a part.

[0009] It is an object of the present application to provide a forging of a part.

[0010] It is an object of the present application to provide a method for obtaining a critical size of alpha phase microtexture leading to a hold fatigue failure of a detection site.

[0011] According to one aspect of the present application, a part detection method based on hold fatigue includes: obtaining a critical size of alpha phase microtexture leading to a hold fatigue failure of a detection site of a part; if the size of the alpha phase microtexture of the detection site is greater than the critical size, determining that the part is unqualified; and if the size of the alpha phase microtexture of the detection site is less than or equal to the size of the part, determining that the part is qualified.

[0012] In one or more embodiments of the part detection method, the step of obtaining the critical size of the alpha phase microtexture leading to the hold fatigue failure of the detection site of the part includes: causing the detection site of the part to have a hold fatigue failure; obtaining an alpha grain distribution within a range of 30° from a stress axis corresponding to an alpha grain c-axis of a hold fatigue fracture of the detection site of the part, to obtain a size of an alpha grain cluster; obtaining a microtexture size of a secondary crack of the hold fatigue failure; and if the size of the alpha grain cluster is consistent with the microtexture size of the secondary crack, the size of the alpha grain cluster is the critical size of the alpha phase microtexture of the detection site of the part.

[0013] In one or more embodiments of the part detection method, an X-ray three-dimensional imaging of the hold fatigue fracture of the detection site of the part is obtained by three-dimensional X-ray scanning (XCT), and a microtexture size of the hold fatigue secondary crack is obtained according to the three-dimensional imaging.

[0014] In one or more embodiments of the part detection method, the microtexture size of the hold fatigue secondary crack is an average value of the microtexture sizes of the secondary cracks above 200 of the hold fatigue.

[0015] In one or more embodiments of the part detection method, the alpha grain distribution within a range of 30° from a stress axis corresponding to an alpha grain c-axis of a hold fatigue fracture of the detection site of the part is obtained by a crystal orientation imaging map of the detection site of the part.

[0016] In one or more embodiments of the part detection method, the crystal orientation imaging map of the detection site of the part is obtained by a scanning microscope, a fatigue crack is initiated and expanded in the form of quasi-cleavage facets in a bright area, and a θ angle range of a hold fatigue expansion facet is below 20°.

[0017] In one or more embodiments of the part detection method, the step of causing the detection site of the part to experience the strain aging fatigue comprises: the detection site of the part is adjacent to a low cycle fatigue sample site of a corresponding stress; obtaining tensile properties of the detection site at room temperature, obtaining yield strength σ 0.2 of the detection site at different temperatures; based on the yield strength σ 0.2 , performing low cycle fatigue loading on the low cycle fatigue sample, performing strain aging fatigue loading on the detection site, and obtaining low cycle fatigue life and strain aging fatigue life.

[0018] In one or more embodiments of the part detection method, the loading parameters of the low cycle fatigue include axial loading, triangular wave, 1s of loading and unloading, and a stress ratio R = 0.05; and the loading parameters of the strain aging fatigue include axial loading, trapezoidal wave, 2min of peak strain aging, 1s of loading and unloading, and a stress ratio R = 0.05.

[0019] In one or more embodiments of the part detection method, the peak value is 0.98σ 0.2 .

[0020] In one or more embodiments of the part detection method, the part is a titanium alloy part, including a titanium alloy forging.

[0021] According to another aspect of the present application, a part detection system comprises: a memory for storing instructions executable by a processor; and the processor for executing the instructions to implement the part detection method described above.

[0022] According to another aspect of the present application, a computer readable medium has a computer program thereon, which is executed by a processor to implement the part detection method described above.

[0023] According to another aspect of the present application, a forging method of a part comprises: obtaining a critical size of α-phase microtexture causing strain aging fatigue failure of a detection site of an initial forging; and if the size of the α-phase microtexture of the detection site is greater than the critical size, increasing a forging deformation corresponding to the detection site for forging of the initial forging until the size of the α-phase microtexture of the detection site is less than or equal to the critical size.

[0024] According to another aspect of the present application, a forging is obtained by the forging method described above.

[0025] In one or more embodiments of the forging, the forging is a titanium alloy forging.

[0026] According to another aspect of this application, a method for obtaining the critical size of the α-phase microtexture leading to fatigue failure at a test site includes: causing fatigue failure at the test site of a part; obtaining the α-grain distribution within a range of 30° deviation of the c-axis of the α-grains from the stress axis corresponding to the fatigue fracture surface at the test site of the part, thereby obtaining the size of the α-grain cluster; obtaining the microtexture size of the secondary crack resulting from fatigue failure; and if the size of the α-grain cluster is consistent with the microtexture size of the secondary crack, then the size of the α-grain cluster is the critical size of the α-phase microtexture at the test site of the part.

[0027] The advantages of this application include, but are not limited to: obtaining the critical size of the α-phase microtexture leading to fatigue failure under load, and then comparing the size of the α-phase microtexture with the critical size to determine whether the fatigue performance of a part is up to standard, saves testing costs and time compared to methods that require numerous tests to obtain the fatigue performance of each part. Furthermore, obtaining this critical size of the α-phase microtexture leading to fatigue failure can also guide the adjustment of the forging process for large-size forgings, reducing the size and strength of the α-phase microtexture by increasing forging deformation in the region above the critical size. This is particularly beneficial for components with low fatigue resistance to forging, such as discs, improving the fatigue resistance of the forgings. Attached Figure Description

[0028] The above and other features, properties and advantages of this application will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0029] Figure 1 This is a schematic flowchart of a part inspection method according to one embodiment.

[0030] Figure 2A , Figure 2B The images show low-cycle fatigue waveforms and load-holding fatigue waveforms corresponding to a part inspection method according to one embodiment.

[0031] Figure 3A , Figure 3B The two methods are X-ray three-dimensional imaging of conventional fatigue fracture surfaces and load-bearing fatigue fracture surfaces, respectively, as embodiments of a part inspection method.

[0032] Figure 4A , Figure 4B The images are crystal orientation imaging diagrams and α-phase diagrams within 30° of the c-axis deviating from the stress axis direction, respectively, representing the microtexture characterization of a part inspection method according to one embodiment.

[0033] Figure 5 This is a flowchart illustrating a method for obtaining the critical size of α-phase microtexture at the detection site that leads to fatigue failure, according to one embodiment.

[0034] Figure 6 This is a flowchart illustrating a method for obtaining the critical size of α-phase microtexture at the detection site that leads to fatigue failure, according to another embodiment.

[0035] Figure 7 This is a schematic block diagram of a parts inspection system according to one embodiment.

[0036] Figure 8 This is a schematic flowchart of a forging method according to one embodiment. Detailed Implementation

[0037] The following discloses various implementation methods or embodiments of the described subject matter technical solutions. To simplify the disclosure, specific examples of the various elements and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of protection of this application.

[0038] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0039] It is understood that flowcharts are used in this application to illustrate the operations performed by the system according to embodiments of this application. It should be understood that, depending on the actual situation, the preceding or following operations may not necessarily be performed precisely in sequence. Other operations may be added to these processes, or one or more steps may be removed from them.

[0040] As mentioned above, in the existing technology, the solution of conducting a large number of load-bearing fatigue failure tests on components to verify whether the components meet the load-bearing fatigue performance requirements requires a large amount of testing costs and testing time.

[0041] Through long-term research, the inventors discovered that for fatigue failure under load, crack initiation occurs below the surface, with cleavage cracks originating at the (0001) plane; the microstructure contains α-clustered structures; fatigue failure under load is pronounced under high stress, and the sensitivity to fatigue failure decreases as the peak fatigue stress decreases. Numerous factors influence the fatigue performance of titanium alloys, including external factors such as peak stress level, holding time, and stress ratio, as well as internal factors related to the alloy itself, such as alloying elements, microstructure, and α-phase microtexture. Among these factors, the inventors found that the α-phase microtexture, as the initiation source region for fatigue failure cracks, has a crucial impact on the service life and strength of parts under fatigue failure conditions, particularly in terms of its size and texture strength.

[0042] Based on the above, the inventors propose a part inspection method, inspection system, computer-readable medium, forging method, and forging based on load-holding fatigue, as well as a method for obtaining the critical size of the α-phase microtexture leading to load-holding fatigue failure at the inspection site. By obtaining this key parameter—the critical size of the α-phase microtexture leading to load-holding fatigue failure—and comparing the size of the α-phase microtexture with the critical size to determine whether the part's load-holding fatigue performance is up to standard, this method saves on testing costs and time compared to methods that require numerous experiments to obtain the load-holding fatigue performance of each part. Furthermore, by obtaining this key parameter, the critical size of the α-phase microtexture leading to load-holding fatigue failure, the forging process of large-size forgings can be adjusted. By increasing the forging deformation in the region above the critical size, the size and strength of the α-phase microtexture can be reduced. Especially for components with low load-holding fatigue sensitivity to forging, such as discs, the load-holding fatigue resistance of the forgings can be improved.

[0043] refer to Figure 1 As shown, in some embodiments, the method for inspecting a part may include the following steps:

[0044] S100: Obtain the critical size of the α-phase microtexture at the test site of the part that leads to fatigue failure under load;

[0045] S201: If the size of the α-phase microtexture at the test site is greater than the critical size, the part is deemed unqualified.

[0046] S202: If the size of the α-phase microtexture at the test site is less than or equal to the size of the part, then the part is deemed qualified.

[0047] refer to Figure 5 as well as Figure 6 As shown, the specific steps for obtaining the critical size of the α-phase microtexture leading to load-bearing fatigue failure at the test site of the part can be as follows:

[0048] S101: Causes load-bearing fatigue failure at the inspection point of the part;

[0049] S102: Obtain the α grain distribution within a range of 30° deviation of the c-axis of the α grains from the stress axis corresponding to the load-bearing fatigue fracture surface of the detection part of the part, and obtain the size of the α grain cluster;

[0050] S103: Obtain the microtexture size of the secondary crack in the fatigue failure under load-preserving conditions;

[0051] S104: If the size of the α grain cluster is consistent with the microtexture size of the secondary crack, then the size of the α grain cluster is the critical size of the α phase microtexture of the detection part of the component.

[0052] It is understandable that this is not necessary for every test. Figure 5 , Figure 6 The steps shown obtain the critical size of the α-phase microtexture leading to load-bearing fatigue failure at the inspection site of the part. After obtaining the critical size data of the α-phase microtexture leading to load-bearing fatigue failure at the inspection site of the part through experiments, subsequent inspections only need to call the above critical size data from the database. Alternatively, the above critical size data can also be obtained by simulation methods such as digital twins, and neither is a limitation.

[0053] The steps described above, which involve obtaining the critical size of the α-phase microtexture at the test site of the part that leads to fatigue failure under load, will be further illustrated using a sample from a Ti6242 disc forging of a high-pressure compressor for an engine as an example.

[0054] First, for sampling at the testing site, samples were taken from the Ti6242 disc forging of the high-pressure compressor in the engine. To accurately assess the load-holding effect, the sampling locations for load-holding fatigue and low-cycle fatigue specimens under corresponding stresses were close to each other.

[0055] Tensile property tests were performed on the samples: the tensile properties of the samples at room temperature were measured to obtain the yield strength σ of the forged samples at different temperatures. 0.2 .

[0056] In addition, for room temperature routine low-cycle fatigue and fatigue life testing under load and fatigue sensitivity:

[0057] Hold-load fatigue is a fatigue phenomenon that occurs under sustained loading at low temperatures. Fatigue cracks initiate at the subsurface of the specimen, with flat cleavage planes at the initiation point. The life of hold-load fatigue is shorter than that of ordinary fatigue. The decrease in hold-load fatigue life (i.e., the strength of the hold-load effect, also known as hold-load fatigue susceptibility) is usually evaluated using the following formula:

[0058]

[0059] Since both conventional low-cycle fatigue and sustained-load fatigue strength are positively correlated with yield strength, different yield strengths result in different fatigue strengths. To avoid the influence of yield strength caused by different processes on fatigue performance, the peak stress is divided by the yield stress at that temperature to obtain the stress coefficient. The fatigue test loading waveform is shown below. Figure 2A , Figure 2B As shown. In some embodiments, as Figure 2A As shown, the ordinary low-cycle fatigue is subjected to axial loading, a triangular wave, with loading and unloading each lasting 1 second, and a stress ratio R = 0.05. Figure 2B As shown, the fatigue test results were obtained by axial loading, stress control, trapezoidal wave, peak load holding time of 2 min, loading and unloading time of 1 s each, and stress ratio R = 0.05. The results of conventional low-cycle fatigue and fatigue tests are shown in Table 1.

[0060] Table 1: 0.98σ of Ti6242 alloy at room temperature 0.2 Peak stress fatigue, normal fatigue life, and fatigue sensitivity under load

[0061]

[0062] Ti6242 alloy forgings can be obtained at room temperature with a strength of 0.98σ. 0.2 Under peak stress, it exhibits load-holding fatigue sensitivity, with a load-holding effect of approximately 5.

[0063] The microtexture dimensions of secondary cracks resulting from load-bearing fatigue failure can be obtained by using three-dimensional X-ray scanning (XCT) to obtain three-dimensional X-ray images of the load-bearing fatigue fracture surface of the tested area of ​​the part, and then using these three-dimensional images to determine the microtexture dimensions of the secondary cracks resulting from load-bearing fatigue failure. Specifically, this can be achieved as follows.

[0064] Quantitative analysis of secondary cracks inside conventional fatigue and load-holding fatigue fracture surfaces was performed using three-dimensional XCT technology, with a crack density of 0.98σ. 0.2 The secondary crack images of conventional low-cycle fatigue and load-holding fatigue under peak stress are as follows: Figure 3A , Figure 3B As shown, conventional low-cycle fatigue samples, besides initiation cracks, exhibit a small number of internal secondary cracks, while load-holding fatigue samples contain a large number of internal secondary cracks. According to XCT results, the load-holding fatigue samples contain a total of 282 secondary cracks, with an average microtexture size of ~67 μm. It can be understood that the microtexture size of the load-holding fatigue secondary cracks is the average of the microtexture sizes of more than 200 secondary cracks in the load-holding fatigue, indicating good data accuracy. The occurrence of internal load-holding fatigue cracks is closely related to the presence of soft-hard orientation microtextures. The size and morphology of the load-holding fatigue secondary cracks obtained by XCT can reflect the microtexture size and morphology in this Ti6242 disk component. Overall, the average microtexture size is ~67 μm, corresponding to approximately 5–8 primary α phases.

[0065] The step of obtaining the α-grain distribution within a 30° range of the c-axis deviation from the stress axis corresponding to the load-bearing fatigue fracture surface of the tested part, and obtaining the size of the α-grain cluster, can be specifically obtained by using a crystal orientation imaging image of the tested part to obtain the α-grain distribution within a 30° range of the c-axis deviation from the stress axis corresponding to the load-bearing fatigue fracture surface of the tested part. Alternatively, a crystal orientation imaging image of the tested part can be obtained by scanning microscopy, in which fatigue cracks initiate and propagate in the form of quasi-cleavage planes in the bright region, and the θ angle range of the load-bearing fatigue propagation planes is less than 20°.

[0066] Specifically, taking Ti6242 disc forgings as an example, cracks in conventional low-cycle fatigue all initiate on the outer surface of the specimen. Crack initiation inside the fracture surface during load-holding fatigue is mainly related to the presence of soft and hard orientation microtextures in the material. The interaction between soft and hard orientations promotes the initiation of load-preserving cracks, which then propagate within the hard-oriented microtexture in the form of quasi-cleavage facets (for details, please refer to reference 1: SINHA V, SPOWART JE, MILLS MJ, et al. Observations on the faceted initiationsite in the dwell-fatigue tested Ti-6242 alloy: Crystallographic orientation and size effects[J]. Metall Mater Trans A-Phys Metall Mater Sci, 2006, 37A(5): 1507-18). These quasi-cleavage facets are approximately perpendicular to the stress axis in spatial orientation, while the facets on conventional fatigue fracture surfaces have a larger tilt angle to the stress axis in spatial orientation (for details, please refer to reference 2: PILCHAK AL, WILLIAMS JC. Observations of facet formation in near-alpha titanium and comments on the role of hydrogen[J]. Metall Mater Trans A, 2011, 42A(4): 1000-27.), therefore, the bright spot region initiating inside the fatigue fracture surface is brighter than the region initiating on the outer surface of conventional fatigue. Using a scanning microscope to observe the bright region on the fatigue fracture surface, fatigue cracks initiating and propagating in the form of quasi-cleavage planes within the bright region, with the θ angle of the fatigue propagation planes below 20°. The hard-oriented microtexture region within 30° of the c-axis of the α-grain deviating from the stress axis is prone to the initiation and propagation of fatigue cracks (see reference 1 above), consistent with the maximum spatial orientation deviation of the fatigue propagation planes from the stress axis of ~20° plus the maximum crystal orientation deviation from the {0001} basal plane of ~10° in the literature. Based on this result, in Figure 4A The microstructure and microtexture experiments revealed α-grains within a 30° range of c-axis deviation from the TD direction, and their distribution is as follows: Figure 4B As shown, there are many island-like regions surrounded by hard-oriented α grains. These island-like regions contain approximately 5 to 10 α grains. The size of the above α grain clusters is consistent with the average microtexture size reflected by XCT detection of secondary fatigue cracks in S103. Figure 4BThe size of the α-grain clusters shown in the figure is the critical size of the α-phase microtexture that leads to fatigue failure of the material.

[0067] refer to Figure 7 As shown, another aspect of this application provides a part inspection system 100, including: a memory 101 for storing instructions executable by a processor; and a processor 102 for executing the instructions to implement the part inspection method described in the above embodiments.

[0068] It should be noted that the aforementioned memory, processor, and database are not limited to a specific memory, processor, or database. For example, in some cases, the memory and processor can have a distributed structure. For instance, it can include a memory and processor located at the detection device end and the backend cloud end, respectively, with the detection device end and the backend cloud end jointly implementing the aforementioned part detection method. Furthermore, in embodiments employing a distributed structure, the specific execution terminal for each step can be adjusted according to actual conditions, and the specific implementation scheme of each step on a particular terminal should not limit the scope of protection of this application.

[0069] Another aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the detection method as described in the above embodiments. For details, please refer to the description above, which will not be repeated here.

[0070] In addition, it is understood that the aforementioned computer-readable storage medium may also be in the form of a system, that is, including multiple computer-readable storage sub-media, so as to jointly implement the steps of the detection method described above through multiple computer-readable storage media.

[0071] like Figure 8 As shown, this application also provides a forging method for a part, comprising:

[0072] S1001: Obtain the critical size of the α-phase microtexture at the test site of the initial forging that leads to fatigue failure under load;

[0073] S1002: If the size of the α-phase microtexture at the detection location is greater than the critical size, then for the forging of the initial forging, increase the forging deformation corresponding to the detection location until the size of the α-phase microtexture at the detection location is less than or equal to the critical size.

[0074] This application also provides a forging obtained by the forging method described in the above embodiments. In some embodiments, the forging is a titanium alloy forging.

[0075] By using the iterative method of S1002, the critical size of the α-phase microtexture leading to fatigue failure can be obtained as a key parameter. This can guide the adjustment of the forging process for large-sized forgings. By increasing the forging deformation in the region above the critical size, the size and strength of the α-phase microtexture can be reduced. This is especially beneficial for components with low fatigue sensitivity to forging, such as discs, improving the fatigue resistance of forgings. Compared to some comparative methods that improve the fatigue resistance of forgings by increasing deformation work in the manufacturing process, selecting process parameters that reduce α grains during the forging process of billets and parts, controlling the appearance of microtexture and α-bundle structures, and performing heat treatment at temperatures close to the β-transformation temperature to minimize the volume fraction of the α-phase, the forging method of this embodiment is simpler.

[0076] like Figure 5 , Figure 6 As shown, this application also provides a method for obtaining the critical size of the α-phase microtexture that leads to fatigue failure at the detection site, comprising:

[0077] S101: Causes load-bearing fatigue failure at the inspection point of the part;

[0078] S102: Obtain the α grain distribution within a range of 30° deviation of the c-axis of the α grains from the stress axis corresponding to the load-bearing fatigue fracture surface of the detection part of the part, and obtain the size of the α grain cluster;

[0079] S103: Obtain the microtexture size of the secondary crack in the fatigue failure under load-preserving conditions;

[0080] S104: If the size of the α grain cluster is consistent with the microtexture size of the secondary crack, then the size of the α grain cluster is the critical size of the α phase microtexture of the detection part of the component.

[0081] In summary, the beneficial effects of the above embodiments regarding the part inspection method, inspection system, computer-readable medium, forging method, forging, and method for obtaining the critical size of the α-phase microtexture leading to fatigue failure at the inspection site include, but are not limited to, obtaining the critical size of the α-phase microtexture leading to fatigue failure as a key parameter, and comparing the size of the α-phase microtexture with the critical size to determine whether the fatigue performance of the part is qualified. Compared with the approach of obtaining the fatigue performance of each part through a large number of tests, this method saves testing costs and time. Furthermore, by obtaining the critical size of the α-phase microtexture leading to fatigue failure as a key parameter, the forging process of large-size forgings can also be adjusted. By increasing the forging deformation in the region above the critical size, the size and strength of the α-phase microtexture can be reduced. Especially for components with low fatigue sensitivity to forging, such as discs, the fatigue resistance of the forgings can be improved.

[0082] The various illustrative logic modules and circuits described in conjunction with the embodiments disclosed herein may be implemented or performed using a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general-purpose processor may be a microprocessor, but in alternatives, it may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors cooperating with a DSP core, or any other such configuration.

[0083] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of both. The software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor such that the processor can read and write information to / from the storage medium. In an alternative, the storage medium may be integrated into the processor. The processor and storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and storage medium may reside as discrete components in the user terminal.

[0084] In one or more exemplary embodiments, the described functionality may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software as a computer program product, the functionality may be stored or transmitted as one or more instructions or code on or via a computer-readable medium. A computer-readable medium includes both computer storage media and communication media, encompassing any medium that facilitates the transfer of a computer program from one location to another. A storage medium may be any available medium accessible to a computer. By way of example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and is accessible to a computer. Any connection is also legitimately referred to as a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of a medium. As used in this article, disk and disc include compact discs (CDs), laser discs, optical discs, digital multi-purpose discs (DVDs), floppy disks, and Blu-ray discs. Disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of these should also be included within the scope of computer-readable media.

[0085] While this application discloses preferred embodiments as described above, it is not intended to limit the scope of this application. Any changes and modifications can be made by those skilled in the art without departing from the spirit and scope of this application. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application, without departing from the content of the technical solution of this application, fall within the protection scope defined by the claims of this application.

Claims

1. A method of part inspection, characterized by, comprising: obtaining a critical size of alpha phase microtexture leading to the persistent fatigue failure of the detection site of the part; if the size of the alpha phase microtexture of the detection site is greater than the critical size, judging that the part is unqualified; if the size of the alpha phase microtexture of the detection site is less than or equal to the part size, judging that the part is qualified.

2. The method of claim 1, wherein The step of obtaining the critical size of alpha phase microtexture leading to the persistent fatigue failure of the detection site of the part comprises: causing the detection site of the part to have a persistent fatigue failure; obtaining the alpha grain distribution within a 30° range of the c-axis of alpha grain deviating from the stress axis corresponding to the persistent fatigue fracture of the detection site of the part, to obtain the size of the alpha grain cluster; obtaining the microtexture size of the secondary crack of the persistent fatigue failure; if the size of the alpha grain cluster is consistent with the microtexture size of the secondary crack, the size of the alpha grain cluster is the critical size of the alpha phase microtexture of the detection site of the part.

3. The method of claim 2, wherein The X-ray three-dimensional imaging of the persistent fatigue fracture of the detection site of the part is obtained by three-dimensional X-ray scanning (XCT), and the microtexture size of the persistent fatigue secondary crack is obtained according to the three-dimensional imaging.

4. The method of claim 3, wherein The microtexture size of the persistent fatigue secondary crack is the average value of the microtexture sizes of more than 200 secondary cracks of the persistent fatigue.

5. The method of claim 2, wherein The alpha grain distribution within a 30° range of the c-axis of alpha grain deviating from the stress axis corresponding to the persistent fatigue fracture of the detection site of the part is obtained through the crystal orientation imaging map of the detection site of the part.

6. The method of claim 5, wherein The crystal orientation imaging map of the detection site of the part is obtained by a scanning electron microscope, and the fatigue crack is initiated and expanded in the form of quasi-cleavage facets in a bright area, and the θ angle range of the persistent fatigue expansion facet is less than or equal to 20°.

7. The method of claim 2, wherein The step of causing the detection site of the part to have a persistent fatigue failure comprises: The detection site of the part is adjacent to the sampling position of the corresponding stress low cycle fatigue sample; obtaining the tensile properties of the test site at room temperature, obtaining the yield strength σ 0.2 at different temperatures of the test site Based on the yield strength σ 0.2 A low-cycle fatigue test specimen is subjected to low-cycle fatigue loading, and the monitoring portion is subjected to hold fatigue loading, to obtain a low-cycle fatigue life and a hold fatigue life.

8. The method of claim 7, wherein The loading parameters of the low cycle fatigue include axial loading, triangular wave, loading and unloading each for 1s, and stress ratio R=0.05; the loading parameters of the persistent fatigue include axial loading, trapezoidal wave, peak value persistent for 2min, loading and unloading each for 1s, and stress ratio R=0.

05.

9. The method of claim 7, wherein The peak is 0.98σ 0.2 .

10. The method of claim 1, wherein The part is a titanium alloy part, including a titanium alloy forge piece.

11. A part inspection system characterized by, comprising: a memory for storing instructions executable by a processor; a processor for executing the instructions to implement the part detection method according to any one of claims 1 to 10.

12. A computer readable medium having a computer program thereon, characterized in that, The program is executed by the processor to implement the part detection method according to any one of claims 1 to 10.

13. A method of forging a part, characterized by, comprising: obtaining a critical size of alpha phase microtexture leading to the persistent fatigue failure of the detection site of the initial forge piece; if the size of the alpha phase microtexture of the detection site is greater than the critical size, increasing the forging deformation corresponding to the detection site for the forging of the initial forge piece, until the size of the alpha phase microtexture of the detection site is less than or equal to the critical size.

14. A forged article, characterized by, obtained by the forging method according to claim 13.

15. The wrought article of claim 14, wherein, The forge piece is a titanium alloy forge piece.

16. A method of obtaining a critical dimension of an alpha phase microtexture at a test site that leads to a retained fatigue failure, characterized by, comprising: causing the detection site of the part to have a persistent fatigue failure; obtaining the α grain distribution within 30° of the stress axis of the α grain c-axis of the holding fatigue fracture of the detection site of the part, obtaining the size of the α grain cluster; obtaining the micro-texture size of the secondary crack of the holding fatigue failure; if the size of the α grain cluster is consistent with the micro-texture size of the secondary crack, the size of the α grain cluster is the critical size of the α phase micro-texture of the detection site of the part.

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