Method, device, equipment and medium for calculating initial residual stress based on additional stress

Abstract

This invention discloses a method, apparatus, device, and medium for calculating initial residual stress based on additional stress. The method includes: determining a processing strategy based on the current titanium alloy material type, and determining the cutting force volume coefficient matrix and the additional force volume coefficient matrix according to the processing strategy; determining the additional residual stress based on the additional force volume coefficient matrix, and substituting the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress into a pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved; constructing a reverse solution model for the initial residual stress based on the initial residual stress function to be solved, and solving the initial residual stress in the reverse solution model using the Tikhonov regularization method. This invention avoids the drawback of excessive inference errors in the initial residual stress of existing technologies, and improves the accuracy of inferring the initial residual stress of titanium alloy structural components.

Description

Technical Field

[0001] This invention relates to the field of material stress measurement technology, and in particular to a method, apparatus, equipment and medium for calculating initial residual stress based on additional stress. Background Technology

[0002] Residual stress is a fundamental property of materials, introduced during material preparation, forming, and CNC machining. The residual stress field affects the material strength, fatigue life, surface integrity, and machining deformation of structural components. Therefore, residual stress is a crucial factor to consider in the design and manufacture of structural components. Accurately obtaining the global residual stress field of the workpiece is essential for precisely controlling its machining deformation and meeting the high-precision manufacturing requirements of titanium alloy structural components.

[0003] There is a method for inferring the global residual stress field of a structural component based on measuring deformation force. However, the machining process of titanium alloy structural components includes cutting force and material removal, and the previously unknown additional stress in the machined surface area has a large difference in distribution between the two, and the residual stress level in different areas is also different. This leads to a large error in the measurement of titanium alloy materials by the existing technology that only considers the cutting force. Therefore, inferring the global initial residual stress by considering the unknown additional stress in the machined surface remains a challenge. Summary of the Invention

[0004] Based on this, the present invention provides a method, apparatus, equipment and medium for calculating initial residual stress based on additional stress, so as to solve the problem of large error in inferring the global initial residual stress of titanium alloy structural components.

[0005] In a first aspect, embodiments of the present invention provide a method for calculating initial residual stress based on additional stress, the method comprising:

[0006] The processing strategy is determined based on the current titanium alloy processing material type, and the cutting force volume coefficient matrix and the additional force volume coefficient matrix are determined based on the processing strategy.

[0007] The additional residual stress is determined based on the additional force volume coefficient matrix, and the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress are substituted into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved.

[0008] Based on the initial residual stress function to be solved, an inverse solution model for the initial residual stress is constructed, and the initial residual stress is solved in the inverse solution model using the Tikhonov regularization method.

[0009] Secondly, embodiments of the present invention provide a device for calculating initial residual stress based on additional stress, the device comprising:

[0010] The matrix determination module is used to determine the processing strategy based on the current titanium alloy processing material type, and to determine the cutting force volume coefficient matrix and the additional force volume coefficient matrix according to the processing strategy.

[0011] The known quantity substitution module is used to determine the additional residual stress based on the additional force volume coefficient matrix, and substitutes the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved.

[0012] The initial residual stress solution module is used to construct an inverse solution model for the initial residual stress based on the initial residual stress function to be solved, and to solve the initial residual stress in the inverse solution model using the Tikhonov regularization method.

[0013] Thirdly, embodiments of the present invention provide an electronic device, the electronic device comprising:

[0014] At least one processor; and

[0015] A memory communicatively connected to the at least one processor; wherein,

[0016] The memory stores a computer program that can be executed by the at least one processor, which enables the at least one processor to perform a method for calculating initial residual stress based on additional stress as described in any embodiment of the present invention.

[0017] Fourthly, a computer-readable storage medium is also provided, the computer-readable storage medium storing computer instructions, the computer instructions being configured to cause a processor to execute and implement a method for calculating initial residual stress based on additional stress as described in any embodiment of the present invention.

[0018] The technical solution of this invention considers two types of residual stress—cutting residual stress and additional residual stress—based on the premise that the additional stress generated during the cutting operation of titanium alloy structural parts also contains residual stress. A volume coefficient matrix is ​​constructed based on each of these two residual stresses, and a new initial residual stress calculation model is obtained using this matrix. This avoids the drawback of excessively large inference errors in the initial residual stress of existing technologies while improving the accuracy of inferring the initial residual stress of titanium alloy structural parts.

[0019] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of a method for calculating initial residual stress based on additional stress according to Embodiment 1 of the present invention;

[0022] Figure 2 This is a reference drawing of a target titanium alloy structural component applicable to an embodiment of the present invention;

[0023] Figure 3 This is a flowchart of another method for calculating initial residual stress based on additional stress according to Embodiment 2 of the present invention;

[0024] Figure 4 This is a schematic diagram of a device for calculating initial residual stress based on additional stress according to Embodiment 3 of the present invention;

[0025] Figure 5 This is a schematic diagram of an electronic device that implements an embodiment of the present invention, namely, a method for calculating initial residual stress based on additional stress. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] Example 1

[0029] Figure 1 This is a flowchart of a method for calculating initial residual stress based on additional stress, provided in Embodiment 1 of the present invention. This embodiment is applicable to the calculation of global initial residual stress generated during the machining of titanium alloy structural parts. This method can be executed by a device for calculating initial residual stress based on additional stress. This device can be implemented in hardware and / or software and can be configured in material preparation, forming, and CNC machining equipment. Figure 1 As shown, the method includes:

[0030] S110. Determine the processing strategy based on the current titanium alloy processing material model, and determine the cutting force volume coefficient matrix and the additional force volume coefficient matrix according to the processing strategy.

[0031] The processing and preparation processes vary slightly depending on the type of titanium alloy material. For example, in a specific instance, when performing processing operations on a typical aerospace structural component, Ti6Al4V titanium alloy, the processing strategy may include: the location and number of deformation force sensors, the division of the cutting area, the operation sequence of the cutting area, the number of cutting layers and the cutting depth of each layer, etc.

[0032] In this embodiment of the invention, when machining the titanium alloy structure, the influence of two forces is considered: cutting force and additional stress. The cutting force is the force generated by the machining equipment performing the cutting operation, while the additional stress is a non-negligible force acting on the material surface additionally generated during the cutting operation of each layer. Simultaneously, the cutting force volume factor matrix is ​​the volume factor matrix corresponding to the cutting operation obtained in the finite element environment; the additional force volume factor matrix is ​​the volume factor matrix corresponding to the additional stress obtained in the finite element environment.

[0033] For ease of understanding, such as Figure 2 As shown, the target titanium alloy structural component is divided into ten cutting zones including AJ, and the cutting sequence is A→B→C→D→E→F→G→H→I→J. Three fixing fixtures are used to fix the component in the middle area, which are the fixed clamping points (the positions marked "×" in the figure). Four deformation force measuring devices are used to fix the component at the corners, which are the deformation force monitoring points (the positions marked "○" in the figure).

[0034] S120. Determine the additional residual stress based on the additional force volume coefficient matrix, and substitute the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved.

[0035] Let the cutting force volume coefficient matrix be M0, denoted as a1×b1, and the additional force volume coefficient matrix be M1, denoted as a2×b2, where a1=a2, which is the total machining force generated by the cutting operation, encompassing all cutting layers; b1 is the unit cutting residual stress generated by the cutting operation, encompassing all cutting regions; and b2 is the unit additional residual stress variable generated by the additional stress, encompassing all additional stress regions.

[0036] Optionally, before substituting the cutting force volume factor matrix, the additional force volume factor matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model, the following steps are also included:

[0037] The first residual stress calculation expression is obtained by multiplying the cutting force volume coefficient matrix variable with the initial residual stress variable;

[0038] By multiplying the additional force volume coefficient matrix variable with the additional residual stress variable, the second residual stress calculation expression is obtained;

[0039] After adding the first residual stress calculation expression and the second residual stress calculation expression, an equivalent relationship is established with the total deformation force variable to obtain the initial residual stress calculation model.

[0040] If the initial residual stress is set as σ0, then the expression for calculating the first residual stress is M0σ0; similarly, if the additional residual stress variable is set as σ1, then the expression for calculating the second residual stress is M1σ1. If the total deformation force is set as f, then the initial residual stress calculation model can be expressed as M0σ0 + M1σ1 = f.

[0041] Furthermore, by adding the first residual stress calculation expression and the second residual stress calculation expression, and establishing an equivalent relationship with the total deformation force variable, an initial residual stress calculation model is obtained, which may include:

[0042] The first residual stress calculation expression M0σ0, composed of the cutting force volume coefficient matrix variable M0 and the initial residual stress variable σ0, is compared with the expression M0σ0, composed of the additional force volume coefficient matrix variable M0. m and additional residual stress variable σ M The second residual stress calculation expression M constitutes m σ m Adding them together, we get M0σ0+M m σ m ;

[0043] M0σ0+M m σ m By establishing an equivalent relationship with the total deformation force variable f, the initial residual stress calculation model is obtained as: M0σ0+M m σ m =f.

[0044] S130. Construct an inverse solution model for the initial residual stress based on the initial residual stress function to be solved, and use the Tikhonov regularization method to solve the initial residual stress in the inverse solution model.

[0045] Furthermore, the initial residual stress function to be solved is expressed as:

[0046]

[0047] in, is the pseudo-inverse operator of M0; where the cutting force volume coefficient matrix and the additional force volume coefficient matrix are both ill-conditioned matrices.

[0048] Furthermore, based on the initial residual stress calculation model, the initial residual stress function to be solved can be obtained, expressed as: However, it should be noted that, in this embodiment of the invention, the constructed initial residual stress calculation model is highly sensitive to small perturbations in the deformation force monitoring data when solving for the initial residual stress. Therefore, the cutting force volume coefficient matrix M0 is a typical ill-conditioned matrix, and thus cannot be directly compared with... The initial residual stress is solved by dividing the inverse matrix. In this case, the Tikhonov regularization method is introduced, and the initial residual stress value is solved using an inverse problem solution method.

[0049] In this embodiment of the invention, considering that the additional stress generated during the cutting of titanium alloy structural components also contains residual stress, two types of residual stress are considered: cutting residual stress and additional residual stress. Volume coefficient matrices are constructed based on these two types of residual stress, and a new initial residual stress calculation model is obtained using these matrices. This avoids the drawback of excessively large inference errors in the initial residual stress of existing technologies while improving the accuracy of inferring the global initial residual stress of titanium alloy structural components.

[0050] Example 2

[0051] Figure 3 This is a flowchart of another initial residual stress calculation method based on additional residual stress provided in Embodiment 2 of the present invention. This embodiment is a refinement based on the above embodiment, and correspondingly, as shown... Figure 3 As shown, the method specifically includes:

[0052] S310. Determine the processing strategy based on the current titanium alloy processing material model, extract the cutting processing strategy from the processing strategy, and obtain the number of cutting layers, monitoring point data, and cutting area data for the current titanium alloy processing material model from the cutting processing strategy.

[0053] A monitoring point refers to the location where the deformation force measuring equipment is installed. One monitoring point corresponds to one force sensor, such as... Figure 2 As shown in the figure, the monitoring points in this embodiment of the invention are arranged at the four corners of the target titanium alloy structural component. A force sensor is placed at each "○" position in the figure, and the deformation force measuring equipment includes force sensors. Therefore, the monitoring point data includes, but is not limited to, the fixed positions and number of deformation force measuring equipment.

[0054] S320. Determine the number of monitoring points based on the monitoring point data, determine the number of cutting areas based on the cutting area data, and calculate the machining force by multiplying the number of cutting layers, the number of monitoring points, and the number of cutting areas.

[0055] Following the above example, in this embodiment of the invention, the number of cutting layers is set to 8, the number of detection points is 4, and the number of cutting areas is 10. Then the processing force is equal to 320. This processing force is also a1 in the cutting force volume coefficient matrix a1×b1 and a2 in the additional force volume coefficient matrix a2×b2.

[0056] S330. Multiply the number of cutting zones by the number of directions of residual stress to obtain the unit cutting residual stress, and obtain the cutting force volume coefficient matrix based on the machining force and the unit cutting residual stress.

[0057] In the embodiments of the present invention, it is generally assumed that the target titanium alloy structural component has a relatively uniform initial residual stress σ in the XY plane. 0x and σ 0y After the cutting region is defined, the initial residual stress in both directions remains unchanged, and the unit cutting residual stress b2 encompasses the entire cutting region, which is 10*2=20. Therefore, the cutting force volume factor matrix M0 can be 320×20.

[0058] Optionally, after determining the cutting force volume coefficient matrix according to the machining strategy, it may also include:

[0059] Extract additional processing strategies from the processing strategy, and obtain the number of additional force regions for the current titanium alloy processing material model from the additional processing strategies;

[0060] The number of cutting layers in the machining strategy is obtained in the machining strategy, and the unit additional residual stress is calculated based on the number of cutting layers and the number of additional force regions.

[0061] Obtain the machining force obtained using the cutting strategy, and obtain the additional force volume coefficient matrix based on the machining force and the unit additional residual stress.

[0062] Specifically, additional machining strategies refer to machining strategies based on the additional stress on the cutting surface caused by the cutting operation. These strategies can include multiple additional stress regions divided along the depth direction under each cutting layer, such as... Figure 4As shown. In this embodiment of the invention, the plurality of additional stress regions may include five types: workpiece, chip, tool, machined surface, and residual stress distribution on the machined surface.

[0063] In the specific example given in the embodiments of the present invention, the number of additional stress regions is 5 and the number of cutting layers is 8, then the unit additional residual stress is equal to 40, that is, 5*8, and the additional force volume coefficient matrix M1 can be 320×40.

[0064] S340. Determine the additional residual stress based on the additional force volume coefficient matrix, and substitute the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved.

[0065] Since the volume coefficient matrix M1 of the additional force is composed of a2×b2, b2 is also the additional residual stress σ. M , where is a known quantity. In the initial residual stress calculation model M0σ0+M m σ m =f, the cutting force volume factor matrix M0, the additional force volume factor matrix M1, and the additional residual stress σ are included. M Substituting the known quantity, σ0 is the only unknown quantity, which is the initial residual stress value.

[0066] Optionally, the cutting force volume factor matrix, the additional force volume factor matrix, and the additional residual stress are substituted into a pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved, which further includes:

[0067] In the monitoring point data, the deformation force collected by the sensors deployed at each monitoring point is obtained, and the total deformation force is obtained by summing them.

[0068] Substituting the cutting force volume factor matrix, the additional force volume factor matrix, the additional residual stress, and the total value of the deformation force into the pre-constructed initial residual stress calculation model, the initial residual stress function to be solved is obtained.

[0069] S350, Using regularization operators Replace the pseudo-inverse operator Obtain the inverse solution model The initial residual stress is then solved in the inverse solution model.

[0070] Where, λ * G represents the hyperparameters obtained based on the preferred generalized cross-validation method, and G is the preset weight matrix.

[0071] Preferably, G, as the preset weight matrix, can be an identity matrix.

[0072] The technical solution of this invention refines the overall solution, focusing on the construction of the cutting force volume coefficient matrix and the additional force volume coefficient matrix. Specifically, since different types of titanium alloy structural parts correspond to different processing strategies, the values ​​of the cutting force volume coefficient matrix variables and the additional force volume coefficient matrix variables can be flexibly changed under different processing strategies. This not only allows for the calculation of the initial residual stress of the entire titanium alloy structure, but is also applicable to different types of titanium alloy structural parts, exhibiting strong versatility and adaptability.

[0073] Example 3

[0074] Figure 4 This is a schematic diagram of a continuity testing fault diagnosis device provided in Embodiment 3 of the present invention. Figure 4 As shown, the device includes:

[0075] The matrix determination module 410 is used to determine the processing strategy based on the current titanium alloy processing material model, and to determine the cutting force volume coefficient matrix and the additional force volume coefficient matrix according to the processing strategy.

[0076] The known quantities are substituted into module 420 to determine the additional residual stress based on the additional force volume coefficient matrix. The cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress are then substituted into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved.

[0077] The initial residual stress solution module 430 is used to construct an inverse solution model of the initial residual stress based on the initial residual stress function to be solved, and to solve the initial residual stress in the inverse solution model using the Tikhonov regularization method.

[0078] This invention, assuming that the additional stress generated during the cutting of titanium alloy structural components also contains residual stress, considers two types of residual stress: cutting residual stress and additional residual stress. Based on these two types of residual stress, volume coefficient matrices are constructed, and a new initial residual stress calculation model is obtained. This avoids the drawback of excessively large inference errors in the initial residual stress of existing technologies, while improving the accuracy of inferring the global initial residual stress of titanium alloy structural components.

[0079] Optionally, based on the above embodiments, the matrix determination module further includes:

[0080] The cutting strategy extraction unit is used to extract the cutting strategy from the machining strategy, and to obtain the number of cutting layers, monitoring point data and cutting area data for the current titanium alloy material model from the cutting strategy;

[0081] The machining force calculation module is used to determine the number of monitoring points based on the monitoring point data, determine the number of cutting areas based on the cutting area data, and calculate the machining force by multiplying the number of cutting layers, the number of monitoring points, and the number of cutting areas.

[0082] The cutting force volume factor matrix calculation module is used to multiply the number of cutting regions by the number of directions of residual stress to obtain the unit cutting residual stress, and to obtain the cutting force volume factor matrix based on the machining force and the unit cutting residual stress.

[0083] Based on the above embodiments, it also includes an additional force volume coefficient matrix calculation unit, which is used to extract additional processing strategies from the processing strategies after determining the cutting force volume coefficient matrix according to the processing strategies, and obtain the number of additional force regions for the current titanium alloy processing material model in the additional processing strategies.

[0084] The number of cutting layers in the machining strategy is obtained in the machining strategy, and the unit additional residual stress is calculated based on the number of cutting layers and the number of additional force regions.

[0085] Obtain the machining force obtained using the cutting strategy, and obtain the additional force volume coefficient matrix based on the machining force and the unit additional residual stress.

[0086] Based on the above embodiments, it also includes an initial residual stress calculation model construction unit, which is used to multiply the cutting force volume coefficient matrix variable with the initial residual stress variable before substituting the cutting force volume coefficient matrix, the additional force volume coefficient matrix and the additional residual stress into the pre-constructed initial residual stress calculation model, to construct the first residual stress calculation expression.

[0087] By multiplying the additional force volume coefficient matrix variable with the additional residual stress variable, the second residual stress calculation expression is obtained;

[0088] After adding the first residual stress calculation expression and the second residual stress calculation expression, an equivalent relationship is established with the total deformation force variable to obtain the initial residual stress calculation model.

[0089] Based on the above embodiments, the initial residual stress calculation model construction unit can also be used for:

[0090] The first residual stress calculation expression M0σ0, composed of the cutting force volume coefficient matrix variable M0 and the initial residual stress variable σ0, is compared with the expression M0σ0, composed of the additional force volume coefficient matrix variable M0. m and additional residual stress variable σ M The second residual stress calculation expression M constitutes m σ m Adding them together, we get M0σ0+M m σm ;

[0091] M0σ0+M m σ m By establishing an equivalent relationship with the total deformation force variable f, the initial residual stress calculation model is obtained as: M0σ0+M m σ m =f.

[0092] Based on the above embodiments, the residual stress substitution module 420 may further include:

[0093] In the monitoring point data, the deformation force collected by the sensors deployed at each monitoring point is obtained, and the total deformation force is obtained by summing them.

[0094] Substituting the cutting force volume factor matrix, the additional force volume factor matrix, the additional residual stress, and the total value of the deformation force into the pre-constructed initial residual stress calculation model, the initial residual stress function to be solved is obtained.

[0095] Based on the above embodiments, the initial residual stress function to be solved is expressed as:

[0096]

[0097] in, is the pseudo-inverse operator of M0; where the cutting force volume coefficient matrix and the additional force volume coefficient matrix are both ill-conditioned matrices.

[0098] Based on the above embodiments, the initial residual stress solving module 430 can be used for:

[0099] Use regularization operators Replace the pseudo-inverse operator Obtain the inverse solution model The initial residual stress is then solved in the inverse solution model.

[0100] Where, λ * G represents the hyperparameters obtained based on the preferred generalized cross-validation method, and G is the preset weight matrix.

[0101] The device for calculating initial residual stress based on additional stress provided in the embodiments of the present invention can execute the method for calculating initial residual stress based on additional stress provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the method.

[0102] Example 4

[0103] Figure 5A schematic diagram of an electronic device 10 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0104] like Figure 5 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0105] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0106] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as a method for calculating initial residual stress based on additional stress.

[0107] That is: determine the processing strategy based on the current titanium alloy processing material type, and determine the cutting force volume coefficient matrix and the additional force volume coefficient matrix according to the processing strategy;

[0108] The additional residual stress is determined based on the additional force volume coefficient matrix, and the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress are substituted into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved.

[0109] Based on the initial residual stress function to be solved, an inverse solution model for the initial residual stress is constructed, and the initial residual stress is solved in the inverse solution model using the Tikhonov regularization method.

[0110] In some embodiments, a method for calculating initial residual stress based on additional stress may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the method for calculating initial residual stress based on additional stress described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform a method for calculating initial residual stress based on additional stress by any other suitable means (e.g., by means of firmware).

[0111] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0112] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0113] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0114] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0115] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0116] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0117] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0118] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for calculating initial residual stress based on additional stress, characterized in that, include: The processing strategy is determined based on the current titanium alloy processing material type, and the cutting force volume coefficient matrix and the additional force volume coefficient matrix are determined based on the processing strategy. The additional residual stress is determined based on the additional force volume coefficient matrix, and the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress are substituted into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved. Based on the initial residual stress function to be solved, an inverse solution model for the initial residual stress is constructed, and the initial residual stress is solved in the inverse solution model using the Tikhonov regularization method. Before substituting the cutting force volume factor matrix, the additional force volume factor matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model, the following steps are also included: The first residual stress calculation expression is obtained by multiplying the cutting force volume coefficient matrix variable with the initial residual stress variable; By multiplying the additional force volume coefficient matrix variable with the additional residual stress variable, the second residual stress calculation expression is obtained; After adding the first residual stress calculation expression and the second residual stress calculation expression, an equivalent relationship is established with the total deformation force variable to obtain the initial residual stress calculation model; After adding the first and second residual stress calculation expressions, an equivalent relationship is established with the total deformation force variable to obtain the initial residual stress calculation model, including: The cutting force volume coefficient matrix variables Initial residual stress variables The first residual stress calculation expression constitutes , and the volume coefficient matrix variables of the additional force and additional residual stress variables The formula for calculating the second residual stress is as follows: Add them together to get ; Will With the total value of deformation force variable By establishing equivalence relations, the initial residual stress calculation model is obtained as follows: ; Substituting the cutting force volume factor matrix, the additional force volume factor matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model yields the initial residual stress function to be solved, which further includes: In the monitoring point data, the deformation force collected by the sensors deployed at each monitoring point is obtained, and the total deformation force is obtained by summing them. Substitute the cutting force volume factor matrix, the additional force volume factor matrix, the additional residual stress, and the total value of the deformation force into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved. The initial residual stress function to be solved is expressed as: ； in, for The pseudo-inverse operator; where the cutting force volume coefficient matrix and the additional force volume coefficient matrix are both ill-conditioned matrices; An inverse solution model for the initial residual stress is constructed based on the initial residual stress function to be solved. The initial residual stress is then solved in the inverse solution model using the Tikhonov regularization method, including: Use regularization operators Replace the pseudo-inverse operator The inverse solution model is obtained. The initial residual stress is then solved in the inverse solution model. in, G represents the hyperparameters obtained based on the preferred generalized cross-validation method, and G is the preset weight matrix.

2. The method according to claim 1, characterized in that, The cutting force volume coefficient matrix is ​​determined according to the machining strategy, including: Extract the cutting strategy from the machining strategy, and obtain the number of cutting layers, monitoring point data, and cutting area data for the current titanium alloy material model from the cutting strategy; The number of monitoring points is determined based on the monitoring point data, the number of cutting areas is determined based on the cutting area data, and the machining force is calculated by multiplying the number of cutting layers, the number of monitoring points, and the number of cutting areas. Multiply the number of cutting zones by the number of directions of residual stress to obtain the unit cutting residual stress, and obtain the cutting force volume coefficient matrix based on the machining force and the unit cutting residual stress.

3. The method according to claim 2, characterized in that, After determining the cutting force volume coefficient matrix according to the machining strategy, the following is also included: Extract additional processing strategies from the processing strategy, and obtain the number of additional force regions for the current titanium alloy processing material model from the additional processing strategies; The number of cutting layers in the machining strategy is obtained in the machining strategy, and the unit additional residual stress is calculated based on the number of cutting layers and the number of additional force regions. Obtain the machining force obtained using the cutting strategy, and obtain the additional force volume coefficient matrix based on the machining force and the unit additional residual stress.

4. A device for calculating initial residual stress based on additional stress, characterized in that, include: The matrix determination module is used to determine the processing strategy based on the current titanium alloy processing material type, and to determine the cutting force volume coefficient matrix and the additional force volume coefficient matrix according to the processing strategy. The known quantity substitution module is used to determine the additional residual stress based on the additional force volume coefficient matrix, and substitutes the cutting force volume coefficient matrix, the additional force volume coefficient matrix, and the additional residual stress into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved. The initial residual stress solution module is used to construct an inverse solution model for the initial residual stress based on the initial residual stress function to be solved, and to solve the initial residual stress in the inverse solution model using the Tikhonov regularization method. It also includes: an initial residual stress calculation model construction unit, which is used to multiply the cutting force volume factor matrix variable with the initial residual stress variable before substituting the cutting force volume factor matrix, the additional force volume factor matrix and the additional residual stress into the pre-constructed initial residual stress calculation model, to construct the first residual stress calculation expression; By multiplying the additional force volume coefficient matrix variable with the additional residual stress variable, the second residual stress calculation expression is obtained; After adding the first residual stress calculation expression and the second residual stress calculation expression, an equivalent relationship is established with the total deformation force variable to obtain the initial residual stress calculation model; The initial residual stress calculation model building unit is also used to convert the cutting force volume coefficient matrix variables. Initial residual stress variables The first residual stress calculation expression constitutes , and the volume coefficient matrix variables of the additional force and additional residual stress variables The formula for calculating the second residual stress is as follows: Add them together to get ; Will With the total value of deformation force variable By establishing equivalence relations, the initial residual stress calculation model is obtained as follows: ; The known quantity substitution module also includes: The total deformation force calculation unit is used to obtain the deformation force collected by the sensors arranged at each monitoring point from the monitoring point data, and sum them to obtain the total deformation force value. The initial residual stress function generation unit is used to substitute the cutting force volume coefficient matrix, the additional force volume coefficient matrix, the additional residual stress, and the total value of the deformation force into the pre-constructed initial residual stress calculation model to obtain the initial residual stress function to be solved. The initial residual stress function to be solved is expressed as: ； in, for The pseudo-inverse operator; where the cutting force volume coefficient matrix and the additional force volume coefficient matrix are both ill-conditioned matrices; The initial residual stress solution module is used to solve for the stress using regularization operators. Replace the pseudo-inverse operator The inverse solution model is obtained. The initial residual stress is then solved in the inverse solution model. in, G represents the hyperparameters obtained based on the preferred generalized cross-validation method, and G is the preset weight matrix.

5. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform a method for calculating initial residual stress based on additional stress according to any one of claims 1-3.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute and implement the method for calculating initial residual stress based on additional stress as described in any one of claims 1-3.

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