Ultra-precision cutting workpiece surface quality detection method, device, equipment and medium

Abstract

The present application relates to a method, apparatus, equipment, and medium for detecting the surface quality of an ultra-precision cut workpiece. The method comprises: performing a Fourier transform on a roughness curve to determine the frequency value of the roughness of the workpiece surface, and constructing a workpiece surface roughness model based on the roughness curve and the frequency value; inputting tool parameters, workpiece parameters, machining parameters, and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the lateral, longitudinal, and vertical directions of the workpiece surface; determining the cutting width and the change in the machined surface depth of the workpiece based on the workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth; and determining the machining quality of the workpiece to be inspected based on the change in the cutting width and the machined surface depth. The present application enables ultra-precision cut workpieces to achieve precise dimensions and shapes.

Description

Technical Field

[0001] The present application relates to the field of ultra-precision machining, and in particular to a method for detecting the surface quality of an ultra-precision cutting workpiece, a corresponding device, an electronic device, and a computer-readable storage medium. Background Art

[0002] Ultra-precision cutting is a high-precision machining technology mainly used to manufacture parts that require strict precision and smooth surfaces. It uses special equipment and tools to remove material by rotating the workpiece and cutting with the cutting tool to achieve precise size and shape, which makes it an ideal choice for manufacturing parts that require very precise size and surface quality.

[0003] In ultra-precision cutting, micron-level dimensional control and nanometer-level surface finish are common requirements. However, due to the influence of machining tool shape, machining parameters, material properties, and other conditions, the machined surface is not smooth during finishing, and the degree of roughness is on the same order of magnitude as the finishing cutting depth. Therefore, the roughness of the machined surface in ultra-precision cutting can cause cutting vibration and fluctuations in cutting forces, resulting in different changes in the elastic-plastic deformation of the local metal material, making the topography of the machined surface difficult to detect.

[0004] To sum up, the roughness of the machined surface of ultra-precision cutting workpieces in the existing technology will cause cutting vibration, and at the same time, fluctuations in cutting force will occur, resulting in different changes in the elastic-plastic deformation of local metal materials, which will make the morphology of the machined surface difficult to detect. In order to solve this problem, the applicant has made corresponding explorations. Summary of the Invention

[0005] The purpose of this application is to solve the above problems and provide a method for detecting the surface quality of ultra-precision cutting workpieces, a corresponding device, an electronic device and a computer-readable storage medium.

[0006] In order to meet the various objectives of this application, this application adopts the following technical solutions:

[0007] A method for detecting the surface quality of an ultra-precision cutting workpiece, which is proposed to meet one of the purposes of this application, comprises:

[0008] Obtaining a roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cut workpiece to be tested, performing Fourier transform on the roughness curve, determining a frequency value of the roughness of the surface of the ultra-precision cut workpiece, and constructing a workpiece surface roughness model based on the roughness curve and the frequency value;

[0009] Inputting tool parameters, workpiece parameters, machining parameters, and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal, and vertical directions of the ultra-precision cutting workpiece surface;

[0010] Determining a relationship between an actual cutting depth and a change in the machined surface depth based on a cutting force in a direction perpendicular to the surface of the ultra-precision cutting workpiece, and determining a cutting width and a change in the machined surface depth of the ultra-precision cutting workpiece based on a workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth;

[0011] The machining quality of the ultra-precision cut workpiece to be inspected is determined according to the changes in the cutting width and the depth of the machined surface, so as to complete the quality inspection of the ultra-precision cut workpiece.

[0012] Optionally, the step of constructing a workpiece surface roughness model according to the roughness curve and the frequency value includes:

[0013] The workpiece surface roughness model is:

[0014] h e =Asin(Bx+C),

[0015] Among them, A is the average value of the roughness of the machined surface, and B is determined by the frequency value of the roughness of the workpiece surface calculated after the roughness curve is transformed by Fourier, and its size is The C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, and x is the distance from the cutting starting point.

[0016] Optionally, after the step of obtaining the roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cut workpiece to be inspected, the method includes:

[0017] Determining peak-to-valley values ​​of the surface of the ultra-precision cutting workpiece to be inspected, detecting whether the peak-to-valley values ​​are less than a preset threshold, and directly using the ultra-precision cutting workpiece to be inspected for fine machining if the peak-to-valley values ​​are less than the preset threshold;

[0018] If the peak-to-valley value exceeds a preset threshold, selecting appropriate semi-finishing parameters to perform semi-finishing on the ultra-precision cut workpiece whose peak-to-valley value exceeds the preset threshold, characterizing the surface morphology and surface characteristic parameters obtained by the semi-finishing, and determining a roughness curve of the machined surface;

[0019] Repeating the Fourier transform of the roughness curve to determine the frequency value of the roughness of the ultra-precision cut workpiece surface, constructing a workpiece surface roughness model according to the roughness curve and the frequency value, and obtaining the workpiece surface roughness model of the semi-finished surface.

[0020] Optionally, before the step of determining the relationship between the actual cutting depth and the variation of the machined surface depth based on the cutting force in the vertical direction of the ultra-precision cutting workpiece surface, the method further includes:

[0021] Determining a theoretical cutting depth and an additional cutting depth of a surface of an ultra-precision cutting workpiece to be inspected, and determining an expression for an actual cutting depth of the surface of the ultra-precision cutting workpiece to be inspected based on the theoretical cutting depth and the additional cutting depth;

[0022] The actual cutting depth expression is:

[0023]

[0024] Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth of finishing, θ i It is the angle between the horizontal direction and the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc.

[0025] Optionally, the step of determining a relationship between an actual cutting depth and a change in a machined surface depth based on a cutting force in a direction perpendicular to the surface of the ultra-precision cutting workpiece comprises:

[0026] Performing a nanoindentation experiment on the surface of the ultra-precision cut workpiece to be tested, determining a load applied to the surface of the ultra-precision cut workpiece to be tested and a change in the depth of the machined surface, and determining a relationship between the load and the change in the depth of the machined surface based on the load and the change in the depth of the machined surface;

[0027] A relationship between the actual cutting depth and the amount of change in the machined surface depth is determined based on the relationship between the load and the amount of change in the machined surface depth.

[0028] Optionally, the step of determining a relationship between an actual cutting depth and a change in a machined surface depth based on a cutting force in a direction perpendicular to the surface of the ultra-precision cutting workpiece comprises:

[0029] The relationship between the load and the change in the depth of the machined surface is:

[0030] Δh=G(F t ),

[0031] Among them, F t is the applied load, Δh is the t The change in the depth of the machined surface under the action of the G function represents the change in the depth of the machined surface Δh and the load F t Functional relationship of

[0032] The relationship between the actual cutting depth and the change in the machined surface depth is:

[0033] Δh i =G(k(h i +h e )),

[0034] Where Δh i h is the change in depth of the machined surface at the i-th tool position on the tool tip arc when the cutting distance is x. i is the theoretical cutting depth of the i-th tool position, h e is the additional cutting depth added when the cutting distance is x, and k is the proportional coefficient of cutting force and cutting depth.

[0035] Optionally, the step of determining the cutting width and the change in the machined surface depth of the ultra-precision cutting workpiece based on the workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth includes:

[0036] The workpiece surface quality detection model is:

[0037]

[0038] Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth, d is the finishing cutting distance, h0 is the theoretical cutting depth, A is the average roughness of the machined surface, and the B value is determined by the f value calculated after the roughness curve is passed through FFT, and its size is The C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, x is the distance from the cutting starting point, θ i is the angle between the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc and the horizontal direction, k is the proportional coefficient of cutting force and cutting depth, and the G function represents the relationship between the depth change Δh of the machined surface and the load F t The functional relationship is as follows: y is the cutting width and z is the change in the depth of the machined surface.

[0039] Another object of the present application is to provide an ultra-precision cutting workpiece surface quality detection device, comprising:

[0040] a roughness model construction module configured to obtain a roughness curve and peak-to-valley values ​​corresponding to a surface of an ultra-precision cut workpiece to be inspected, perform Fourier transform on the roughness curve, determine a frequency value of the roughness of the surface of the ultra-precision cut workpiece, and construct a workpiece surface roughness model based on the roughness curve and the frequency value;

[0041] a cutting force determination module configured to input tool parameters, workpiece parameters, machining parameters, and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal, and vertical directions of the ultra-precision cutting workpiece surface;

[0042] a cutting width determination module configured to determine a relationship between an actual cutting depth and a change in a machined surface depth based on a cutting force in a direction perpendicular to the surface of the ultra-precision cutting workpiece, and to determine the cutting width of the ultra-precision cutting workpiece and the change in the machined surface depth based on a workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth;

[0043] The quality detection module is configured to determine the machining quality of the ultra-precision cut workpiece to be detected according to the cutting width and the variation of the machined surface depth, so as to complete the quality detection of the ultra-precision cut workpiece.

[0044] An electronic device provided to meet another purpose of the present application includes a central processing unit and a memory, wherein the central processing unit is used to call and run a computer program stored in the memory to execute the steps of the ultra-precision cutting workpiece surface quality detection method described in the present application.

[0045] A computer-readable storage medium is provided to meet another purpose of the present application, which stores a computer program implemented according to the ultra-precision cutting workpiece surface quality detection method in the form of computer-readable instructions. When the computer program is called and executed by a computer, the steps included in the corresponding method are executed.

[0046] Compared with the prior art, the present application addresses the problems in the prior art where the roughness of the machined surface of ultra-precision cutting workpieces can cause cutting vibration, while also generating fluctuations in cutting force, resulting in different changes in the elastic-plastic deformation of local metal materials, and thus making it difficult to detect the morphology of the machined surface. The present application characterizes the three-dimensional morphology of the machined surface, establishes a roughness model of the machined surface, then discretizes the tool tip arc, establishes an actual cutting depth model of discrete points on the tool tip arc, calculates the effect of cutting depth on the depth of the machined surface through three-dimensional finite element cutting simulation and nanoindentation experiments, and finally establishes a three-dimensional prediction model of the change in the depth of the machined surface to determine the quality of the surface of the ultra-precision cutting workpiece. The present application includes but is not limited to the following beneficial effects:

[0047] The present application can quickly and accurately detect the machined surface of ultra-precision cutting workpieces to quickly identify qualified and unqualified workpieces among ultra-precision cutting workpieces, and can accurately and quickly screen out products that meet the industry standards for ultra-precision cutting workpieces, so that ultra-precision cutting workpieces can achieve precise size and shape, and solve the cutting vibration caused by the roughness of the machined surface of ultra-precision cutting workpieces, which will also cause fluctuations in cutting force, resulting in different changes in the elastic-plastic deformation of local metal materials, thereby making the morphology of the machined surface difficult to detect. It significantly improves the efficiency of ultra-precision cutting surface quality inspection, greatly improves the product qualification rate of ultra-precision cutting workpieces, and lays a solid technical foundation for the development of the ultra-precision cutting workpiece industry, which is conducive to promoting the development of the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0049] Figure 1 This is a flow chart of the method for detecting the surface quality of ultra-precision cutting workpieces in this application;

[0050] Figure 2 A schematic diagram of the microscopic morphology of the workpiece surface in an embodiment of the present application;

[0051] Figure 3 A schematic diagram of a roughness curve of a processed surface in an embodiment of the present application;

[0052] Figure 4 Schematic diagram of Fourier transform analysis of the workpiece surface in an embodiment of the present application;

[0053] Figure 5 Schematic diagram of actual cutting depth for finishing in an embodiment of the present application;

[0054] Figure 6 Schematic diagram of the actual cutting depth of a point on the arc of the tool tip in the embodiment of the present application;

[0055] Figure 7 Schematic diagram of input and output of a three-dimensional finite element simulation model in an embodiment of the present application;

[0056] Figure 8 The vertical cutting force F in the embodiment of this application y Schematic diagram of the relationship with cutting depth h;

[0057] Figure 9 Schematic diagram of the effect of the roughness of the processed surface on the processed surface in an embodiment of the present application;

[0058] Figure 10Schematic diagram of depth variation of the machined surface of an ultra-precision cutting workpiece in an embodiment of the present application;

[0059] Figure 11 This is a principle block diagram of the device for detecting the surface quality of ultra-precision cutting workpieces in an embodiment of the present application;

[0060] Figure 12 Schematic diagram of the structure of the computer device in the embodiment of the present application. DETAILED DESCRIPTION

[0061] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limiting the present application.

[0062] It will be understood by those skilled in the art that, unless expressly stated otherwise, the singular forms "a", "an", "said" and "the" used herein may also include the plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, "connected" or "coupled" as used herein may include wireless connections or wireless couplings. The term "and / or" used herein includes all or any units and all combinations of one or more associated listed items.

[0063] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0064] It will be understood by those skilled in the art that the terms "client," "terminal," and "terminal device" as used herein include both devices that are wireless signal receivers, i.e., devices that only have wireless signal receivers without transmission capabilities, and devices that have receiving and transmitting hardware capable of two-way communication over a two-way communication link. Such devices may include: cellular or other communication devices such as personal computers and tablet computers, which have single-line displays, multi-line displays, or cellular or other communication devices without multi-line displays; PCS (Personal Communications Service), which may combine voice, data processing, fax, and / or data communication capabilities; PDA (Personal Digital Assistant), which may include a radio frequency receiver, a pager, Internet / Intranet access, a web browser, a notepad, a calendar, and / or a GPS (Global Positioning System) receiver; and conventional laptop and / or palmtop computers or other devices, which have and / or include a radio frequency receiver. As used herein, the terms "client," "terminal," or "terminal device" may be portable, transportable, or installed in a vehicle (air, sea, and / or land), or may be adapted and / or configured to operate locally and / or in a distributed manner at any other location on Earth and / or in space. As used herein, the terms "client," "terminal," or "terminal device" may also refer to a communication terminal, an Internet terminal, or a music / video playback terminal, such as a PDA, an MID (Mobile Internet Device), and / or a mobile phone with music / video playback capabilities, or may include a smart TV, a set-top box, or other device.

[0065] The hardware referred to by names such as "server", "client", and "service node" in this application is essentially an electronic device with capabilities equivalent to those of a personal computer. It is a hardware device that has the necessary components revealed by the von Neumann principle, such as a central processing unit (including an arithmetic unit and a controller), a memory, an input device, and an output device. Computer programs are stored in its memory, and the central processing unit loads the program stored in the external memory into the internal memory for execution, executes the instructions in the program, and interacts with the input and output devices to complete specific functions.

[0066] It should be noted that the concept of "server" referred to in this application can also be extended to server clusters. Based on the network deployment principles understood by those skilled in the art, the servers described should be logically divided. In physical space, these servers can be independent of each other but callable through interfaces, or integrated into a single physical computer or a computer cluster. Those skilled in the art should understand this flexibility and should not use it to constrain the implementation of the network deployment method of this application.

[0067] Unless expressly specified, one or more technical features of the present application can be deployed on a server for implementation and accessed by a client through a remote call to obtain an online service interface provided by the server, or can be directly deployed and run on a client for implementation.

[0068] Unless expressly specified otherwise, the neural network models referenced or may be referenced in this application may be deployed on a remote server and remotely called on the client, or may be deployed and directly called on a client with sufficient device capabilities. In some embodiments, when it runs on the client, its corresponding intelligence may be obtained through transfer learning to reduce the requirements for the client's hardware operating resources and avoid excessive occupation of the client's hardware operating resources.

[0069] Unless explicitly specified, the various data involved in this application can be stored remotely on a server or on a local terminal device, as long as they are suitable for being called by the technical solution of this application.

[0070] Those skilled in the art should be aware that although the various methods of this application are described based on the same concept and thus exhibit commonality, unless otherwise specified, these methods can be independently executed. Similarly, the various embodiments disclosed in this application are all based on the same inventive concept. Therefore, concepts with the same expression, as well as concepts that are appropriately transformed for convenience despite different expression, should be understood as equivalent.

[0071] Unless expressly stated to be mutually exclusive, the various embodiments disclosed in this application may be cross-combined with the relevant technical features of the various embodiments to flexibly construct new embodiments, as long as such combination does not deviate from the creative spirit of this application and can meet the needs of the prior art or resolve certain deficiencies in the prior art. Those skilled in the art should be aware of such flexibility.

[0072] Ultra-precision cutting is a high-precision machining technology used primarily to manufacture parts requiring exacting precision and smooth surfaces. It utilizes specialized equipment and tools to remove material by rotating the workpiece and applying cutting tools to achieve precise dimensions and shapes, making it ideal for manufacturing parts requiring extremely precise dimensions and surface quality.

[0073] Based on the above example scenarios, please refer to Figure 1 In one embodiment, the method for detecting the surface quality of an ultra-precision cutting workpiece of the present application includes:

[0074] Step S10, obtaining a roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cut workpiece to be tested, performing Fourier transform on the roughness curve, determining the frequency value of the roughness of the surface of the ultra-precision cut workpiece, and constructing a workpiece surface roughness model based on the roughness curve and the frequency value;

[0075] See also Figure 2 、 Figure 3 as well as Figure 4 The computer terminal device can obtain the roughness curve and peak-to-valley value corresponding to the surface of the ultra-precision cutting workpiece to be detected, and can use a white light interferometer to characterize the surface morphology of the ultra-precision cutting workpiece to be detected, and obtain the characteristic parameters of the machined surface. The characteristic parameters are characterized to obtain the roughness curve and peak-to-valley value (PV) of the machined surface of the ultra-precision cutting workpiece to be detected, and the obtained roughness curve is Fourier transformed (FFT) to obtain the frequency value (f) of the roughness of the machined surface of the ultra-precision cutting workpiece to be detected. According to the above parameters, a surface roughness model of the workpiece is constructed.

[0076] Specifically, the workpiece surface roughness model is:

[0077] h e =Asin(Bx+C),

[0078] Among them, A is the average value of the roughness of the machined surface, and B is determined by the frequency value of the roughness of the workpiece surface calculated after the roughness curve is transformed by Fourier, and its size is The C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, and x is the distance from the cutting starting point.

[0079] In some embodiments, after the step of obtaining the roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cut workpiece to be inspected, the method includes:

[0080] Step S101, determining the peak-to-valley value of the surface of the ultra-precision cutting workpiece to be inspected, detecting whether the peak-to-valley value is less than a preset threshold value, and if the peak-to-valley value is less than the preset threshold value, directly using the ultra-precision cutting workpiece to be inspected for fine machining;

[0081] Step S103: if the peak-to-valley value exceeds a preset threshold, selecting appropriate semi-finishing parameters to perform semi-finishing on the ultra-precision cut workpiece whose peak-to-valley value exceeds the preset threshold, characterizing the surface morphology and surface characteristic parameters obtained by the semi-finishing, and determining a roughness curve of the machined surface;

[0082] Step S105: Repeat the Fourier transform of the roughness curve to determine the frequency value of the roughness of the ultra-precision cut workpiece surface, and construct a workpiece surface roughness model according to the roughness curve and the frequency value to obtain the workpiece surface roughness model of the semi-finished surface.

[0083] Specifically, the preset threshold value can be 10μm, 15μm or 20μm, etc. This application determines the preset threshold value as 10μm, which does not constitute a limitation to this application. Those skilled in the art can determine the corresponding preset threshold value as needed according to actual needs, and obtain the peak-to-valley value (PV) of the machined surface of the ultra-precision cutting workpiece to be detected, and judge whether the peak-to-valley value of the machined surface is less than 10μm (depending on the specific processing situation). If it is less than 10μm, the ultra-precision cutting workpiece to be detected can be directly used for finishing; if it is greater than 10μm, it is necessary to semi-finish the ultra-precision cutting workpiece to be detected first, select appropriate semi-finishing parameters to semi-finish the workpiece with a peak-to-valley value of the machined surface greater than 10μm, characterize the surface morphology and surface feature parameters obtained by semi-finishing, repeatedly perform Fourier transform on the roughness curve, determine the frequency value of the roughness of the ultra-precision cutting workpiece surface, construct a workpiece surface roughness model step according to the roughness curve and the frequency value, and obtain the workpiece surface roughness model of the semi-finished surface.

[0084] Step S20: inputting the tool parameters, workpiece parameters, machining parameters, and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal, and vertical directions of the ultra-precision cutting workpiece surface;

[0085] After constructing the workpiece surface roughness model, the tool parameters, workpiece parameters and processing parameters of the ultra-precision cutting workpiece surface to be tested are determined, and the tool parameters, workpiece parameters and processing parameters as well as the workpiece surface roughness model are input into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal and vertical directions of the ultra-precision cutting workpiece surface.

[0086] In some embodiments, a theoretical cutting depth and an additional cutting depth of the surface of the ultra-precision cutting workpiece to be inspected are determined, and an expression for an actual cutting depth of the surface of the ultra-precision cutting workpiece to be inspected is determined based on the theoretical cutting depth and the additional cutting depth;

[0087] Specifically, see Figure 5 as well as Figure 6 , a tool with a tool tip radius of R is selected for ultra-precision cutting and finishing. The theoretical cutting depth of finishing is h0. Due to the existence of the roughness of the machined surface, the actual cutting depth of the tool will change with the change of the cutting position. An additional cutting depth h is added on the basis of the theoretical cutting depth h0. e , and the cutting depth of each point on the tool tip arc is different. The tool tip arc is discretized in the horizontal direction, and the actual cutting depth expression of each discrete point is expressed as follows:

[0088] The actual cutting depth expression is:

[0089]

[0090] Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth of finishing, θ i It is the angle between the horizontal direction and the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc.

[0091] For further information, see Figure 7 as well as Figure 8 , it can be seen from the actual cutting depth in the above steps that the effect of each point on the tool tip arc on the workpiece surface is also different. Therefore, Abaqus three-dimensional cutting finite element simulation of different depths is performed, and the tool parameters, workpiece parameters, processing parameters and the workpiece surface roughness model are input into the three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal and vertical directions of the ultra-precision cutting workpiece surface. In this way, the cutting forces in the transverse direction x, longitudinal direction y and vertical direction z at different cutting depths can be obtained, and the cutting force F in the vertical direction can be obtained. y Relationship with cutting depth h.

[0092] Depend on Figure 7 as well as Figure 8 It can be seen that the magnitude of the cutting force is affected by various factors. However, when the tool parameters, material parameters and processing parameters are determined, there is a linear relationship between the cutting force and the cutting depth. From this, it can be concluded that the cutting force F in the vertical direction is y The relationship with cutting depth h is expressed as follows:

[0093] F y =kh,

[0094] Where k is the proportional coefficient of cutting force and cutting depth, which is determined by the tool parameters, material parameters, and processing parameters in the input parameters of the 3D cutting finite element simulation model.

[0095] Step S30: determining a relationship between an actual cutting depth and a change in the machined surface depth based on the cutting force in a direction perpendicular to the surface of the ultra-precision cutting workpiece, and determining a cutting width and a change in the machined surface depth of the ultra-precision cutting workpiece based on a workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth;

[0096] The step of determining a relationship between an actual cutting depth and a change in a machined surface depth based on the cutting force in a vertical direction of the ultra-precision cutting workpiece surface comprises:

[0097] Step S301, performing a nanoindentation experiment on the surface of the ultra-precision cut workpiece to be tested, determining the load applied to the surface of the ultra-precision cut workpiece to be tested and the change in the depth of the machined surface, and determining a relationship between the load and the change in the depth of the machined surface based on the load and the change in the depth of the machined surface;

[0098] Step S303: determining a relationship between the actual cutting depth and the change in the machined surface depth based on the relationship between the load and the change in the machined surface depth.

[0099] Specifically, a nanoindentation experiment is performed on the surface of the ultra-precision cut workpiece to be tested to obtain the load (Ft) applied to the surface of the ultra-precision cut workpiece to be tested and the change in the machined surface depth (Δh). Based on the load and the change in the machined surface depth, a relationship between the load and the change in the machined surface depth is determined. The relationship between the load and the change in the machined surface depth is:

[0100] Δh=G(F t ),

[0101] Among them, F t is the applied load, Δh is the t The change in the depth of the machined surface under the action of , which is related to the elastic modulus, hardness, Poisson's ratio, etc. The G function represents the relationship between the change in the depth of the machined surface Δh and the load F t Functional relationship of

[0102] The load (F t ) and the vertical cutting force (F y ) have the same effect on the workpiece, so they can be replaced equivalently to obtain the relationship between the actual cutting depth and the change in the depth of the machined surface, which is expressed as follows:

[0103] The relationship between the actual cutting depth and the change in the machined surface depth is:

[0104] Δh i =G(k(h i +h e )),

[0105] Where Δh i h is the change in depth of the machined surface at the i-th tool position on the tool tip arc when the cutting distance is x. i is the theoretical cutting depth of the i-th tool position, h e is the additional cutting depth added when the cutting distance is x, and k is the proportional coefficient of cutting force and cutting depth.

[0106] For further information, please refer to Figure 9 as well as Figure 10 Due to the influence of the roughness of the machined surface of the ultra-precision cutting workpiece, the cutting depth will increase during the cutting process, and the friction force of the chips on the tool will increase downward, causing the machined surface to show a downward "concave" trend. As the cutting depth increases, the degree of downward "concave" becomes deeper, so the Δh calculated in the above steps is i The action on the machined surface is downward;

[0107] When obtaining the roughness h of the machined surface e , h e The surface quality detection model expression of the workpiece is: the additional cutting depth added when the cutting distance is x, the change in the depth of the machined surface of the ultra-precision cutting workpiece to be detected is expressed as follows:

[0108] The workpiece surface quality detection model is:

[0109]

[0110] Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth, d is the finishing cutting distance, h0 is the theoretical cutting depth, A is the average roughness of the machined surface, and the B value is determined by the f value calculated after the roughness curve is passed through FFT, and its size is The C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, x is the distance from the cutting starting point, θ i is the angle between the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc and the horizontal direction, k is the proportional coefficient of cutting force and cutting depth, and the G function represents the relationship between the depth change Δh of the machined surface and the load F t The functional relationship is as follows: y is the cutting width and z is the change in the depth of the machined surface.

[0111] After determining the workpiece surface quality detection model, the cutting width and the change in the machined surface depth of the ultra-precision cutting workpiece are determined based on the workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth.

[0112] Step S40: determining the machining quality of the ultra-precision cut workpiece to be inspected according to the cutting width and the variation of the machined surface depth, so as to complete the quality inspection of the ultra-precision cut workpiece.

[0113] After determining the changes in the cutting width and the machined surface depth of the ultra-precision cutting workpiece, the processing quality of the ultra-precision cutting workpiece to be tested is determined based on the changes in the cutting width and the machined surface depth to complete the quality inspection of the ultra-precision cutting workpiece. Based on the changes in the cutting width and the machined surface depth, it can be judged whether the surface quality of the workpiece meets the requirements after ultra-precision cutting.

[0114] In some embodiments, after determining the changes in the cutting width and the machined surface depth of the ultra-precision cutting workpiece, weights corresponding to the changes in the cutting width and the machined surface depth are pre-assigned, and the changes in the cutting width and the machined surface depth are weighted averaged based on the weights to determine a weighted average value, or the ratio between the changes in the cutting width and the machined surface depth is calculated based on the weights, and it is detected whether the weighted average value or the ratio exceeds a preset threshold value. If so, the ultra-precision cutting workpiece is determined as an unqualified workpiece. If the weighted average value or the ratio is lower than the preset threshold value, the ultra-precision cutting workpiece is determined as a qualified workpiece, thereby completing the quality inspection of the ultra-precision cutting workpiece to be inspected.

[0115] As can be seen from the above embodiments, compared with the prior art, the present application addresses the problems in the prior art where the roughness of the machined surface of an ultra-precision cutting workpiece causes cutting vibration, while also generating fluctuations in cutting force, resulting in different changes in the elastic-plastic deformation of local metal materials, and thus making it difficult to detect the morphology of the machined surface. The present application characterizes the three-dimensional morphology of the machined surface, establishes a roughness model of the machined surface, then discretizes the tool tip arc, establishes an actual cutting depth model of discrete points on the tool tip arc, calculates the effect of cutting depth on the depth of the machined surface through three-dimensional finite element cutting simulation and nanoindentation experiments, and finally establishes a three-dimensional prediction model of the change in the depth of the machined surface to determine the quality of the surface of the ultra-precision cutting workpiece. The present application includes but is not limited to the following beneficial effects:

[0116] The present application can quickly and accurately detect the machined surface of ultra-precision cutting workpieces to quickly identify qualified and unqualified workpieces among ultra-precision cutting workpieces, and can accurately and quickly screen out products that meet the industry standards for ultra-precision cutting workpieces, so that ultra-precision cutting workpieces can achieve precise size and shape, and solve the cutting vibration caused by the roughness of the machined surface of ultra-precision cutting workpieces, which will also cause fluctuations in cutting force, resulting in different changes in the elastic-plastic deformation of local metal materials, thereby making the morphology of the machined surface difficult to detect. It significantly improves the efficiency of ultra-precision cutting surface quality inspection, greatly improves the product qualification rate of ultra-precision cutting workpieces, and lays a solid technical foundation for the development of the ultra-precision cutting workpiece industry, which is conducive to promoting the development of the industry.

[0117] See also Figure 11 , an ultra-precision cutting workpiece surface quality detection device provided to meet one of the purposes of this application, includes a roughness model construction module 1100, a cutting force determination module 1200, a cutting width determination module 1300 and a quality detection module 1400. Among them, the roughness model construction module 1100 is configured to obtain a roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cutting workpiece to be inspected, perform Fourier transform on the roughness curve, determine the frequency value of the roughness of the ultra-precision cutting workpiece surface, and construct a workpiece surface roughness model based on the roughness curve and the frequency value; the cutting force determination module 1200 is configured to input tool parameters, workpiece parameters, processing parameters and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal and vertical directions of the ultra-precision cutting workpiece surface; the cutting width determination module 1300 is configured to determine the relationship between the actual cutting depth and the change in the machined surface depth based on the cutting force in the vertical direction of the ultra-precision cutting workpiece surface, and determine the cutting width and the change in the machined surface depth of the ultra-precision cutting workpiece based on the workpiece surface quality inspection model and the relationship between the actual cutting depth and the change in the machined surface depth; the quality inspection module 1400 is configured to determine the machining quality of the ultra-precision cutting workpiece to be inspected based on the change in the cutting width and the machined surface depth, so as to complete the quality inspection of the ultra-precision cutting workpiece.

[0118] Based on any embodiment of this application, please refer to Figure 12 Another embodiment of the present application further provides an electronic device, which can be implemented by a computer device, such as Figure 12As shown, a schematic diagram of the internal structure of a computer device. The computer device includes a processor, a computer-readable storage medium, a memory, and a network interface connected via a system bus. Among them, the computer-readable storage medium of the computer device stores an operating system, a database, and computer-readable instructions, and the database may store a control information sequence. When the computer-readable instructions are executed by the processor, the processor can implement a method for detecting the surface quality of an ultra-precision cutting workpiece. The processor of the computer device is used to provide computing and control capabilities to support the operation of the entire computer device. The memory of the computer device may store computer-readable instructions. When the computer-readable instructions are executed by the processor, the processor can execute the ultra-precision cutting workpiece surface quality detection method of the present application. The network interface of the computer device is used to connect and communicate with the terminal. Those skilled in the art will understand that Figure 12 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0119] In this embodiment, the processor is used to execute Figure 11 The memory stores the program code and various data required to execute the specific functions of each module and its submodule in the ultra-precision cutting workpiece surface quality inspection device. The network interface is used to transmit data between user terminals or servers. The memory in this embodiment stores the program code and data required to execute all modules / submodules in the ultra-precision cutting workpiece surface quality inspection device of this application, and the server can call the server's program code and data to execute the functions of all submodules.

[0120] The present application also provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the ultra-precision cutting workpiece surface quality detection method described in any embodiment of the present application.

[0121] The present application also provides a computer program product, including a computer program / instruction, which, when executed by one or more processors, implements the steps of the method for detecting the surface quality of ultra-precision cutting workpieces described in any embodiment of the present application.

[0122] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments of the present application can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the above-mentioned embodiments of the method. The aforementioned storage medium can be a computer-readable storage medium such as a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0123] The above description is only part of the implementation methods of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

[0124] To sum up, the present application can quickly and accurately detect the processed surface of ultra-precision cutting workpieces to quickly identify qualified and unqualified workpieces among ultra-precision cutting workpieces, and can accurately and quickly screen out products that meet the industry standards for ultra-precision cutting workpieces, so that ultra-precision cutting workpieces can achieve precise size and shape.

Claims

1. A method for detecting the surface quality of an ultra-precision cutting workpiece, characterized in that: include: Obtaining a roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cut workpiece to be tested, performing Fourier transform on the roughness curve, determining a frequency value of the roughness of the surface of the ultra-precision cut workpiece, and constructing a workpiece surface roughness model based on the roughness curve and the frequency value; Inputting tool parameters, workpiece parameters, machining parameters, and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal, and vertical directions of the ultra-precision cutting workpiece surface; The relationship between the actual cutting depth and the change in the machined surface depth is determined based on the cutting force in the vertical direction of the ultra-precision cutting workpiece surface. The cutting width of the ultra-precision cutting workpiece and the change in the machined surface depth are determined based on the workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth. The workpiece surface quality detection model is: ， Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth, d is the finishing cutting distance, h0 is the theoretical cutting depth, A is the average roughness of the machined surface, and the B value is determined by the f value calculated after the roughness curve is passed through FFT, and its size is , the C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, x is the distance from the cutting starting point, θ i is the angle between the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc and the horizontal direction, k is the proportional coefficient of cutting force and cutting depth, and the G function represents the change in depth of the machined surface. With load F t Functional relationship, y is the cutting width, z is the change in the depth of the machined surface; The machining quality of the ultra-precision cut workpiece to be inspected is determined according to the changes in the cutting width and the depth of the machined surface, so as to complete the quality inspection of the ultra-precision cut workpiece.

2. The method for detecting the surface quality of ultra-precision cutting workpieces according to claim 1, wherein: The step of constructing a workpiece surface roughness model according to the roughness curve and the frequency value includes: The workpiece surface roughness model is: ， Among them, A is the average value of the roughness of the machined surface, and B is determined by the frequency value of the roughness of the workpiece surface calculated after the roughness curve is transformed by Fourier, and its size is , the C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, and x is the distance from the cutting starting point.

3. The method for detecting the surface quality of ultra-precision cutting workpieces according to claim 1, wherein: After the step of obtaining the roughness curve and peak-to-valley values ​​corresponding to the surface of the ultra-precision cutting workpiece to be inspected, the method includes: Determining peak-to-valley values ​​of the surface of the ultra-precision cutting workpiece to be inspected, detecting whether the peak-to-valley values ​​are less than a preset threshold, and directly using the ultra-precision cutting workpiece to be inspected for fine machining if the peak-to-valley values ​​are less than the preset threshold; If the peak-to-valley value exceeds a preset threshold, selecting appropriate semi-finishing parameters to perform semi-finishing on the ultra-precision cut workpiece whose peak-to-valley value exceeds the preset threshold, characterizing the surface morphology and surface characteristic parameters obtained by the semi-finishing, and determining a roughness curve of the machined surface; Repeating the Fourier transform of the roughness curve to determine the frequency value of the roughness of the ultra-precision cut workpiece surface, constructing a workpiece surface roughness model according to the roughness curve and the frequency value, and obtaining the workpiece surface roughness model of the semi-finished surface.

4. The method for detecting the surface quality of ultra-precision cutting workpieces according to claim 1, wherein: Before the step of determining the relationship between the actual cutting depth and the variation of the machined surface depth based on the cutting force in the vertical direction of the ultra-precision cutting workpiece surface, the method includes: Determining a theoretical cutting depth and an additional cutting depth of a surface of an ultra-precision cutting workpiece to be inspected, and determining an expression for an actual cutting depth of the surface of the ultra-precision cutting workpiece to be inspected based on the theoretical cutting depth and the additional cutting depth; The actual cutting depth expression is: ， Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth of finishing, θ i It is the angle between the horizontal direction and the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc.

5. The method for detecting the surface quality of ultra-precision cutting workpieces according to claim 1, wherein: The step of determining a relationship between an actual cutting depth and a change in a machined surface depth based on the cutting force in a vertical direction of the ultra-precision cutting workpiece surface comprises: Performing a nanoindentation experiment on the surface of the ultra-precision cut workpiece to be tested, determining a load applied to the surface of the ultra-precision cut workpiece to be tested and a change in the depth of the machined surface, and determining a relationship between the load and the change in the depth of the machined surface based on the load and the change in the depth of the machined surface; A relationship between the actual cutting depth and the amount of change in the machined surface depth is determined based on the relationship between the load and the amount of change in the machined surface depth.

6. The method for detecting the surface quality of ultra-precision cutting workpieces according to claim 5, characterized in that: The step of determining a relationship between an actual cutting depth and a change in a machined surface depth based on the cutting force in a vertical direction of the ultra-precision cutting workpiece surface comprises: The relationship between the load and the change in the depth of the machined surface is: ， Among them, F t is the applied load, For load F t The change in depth of the machined surface under the action of G function represents the change in depth of the machined surface. With load F t Functional relationship of The relationship between the actual cutting depth and the change in the machined surface depth is: ， in, h is the change in depth of the machined surface at the i-th tool position on the tool tip arc when the cutting distance is x. i is the theoretical cutting depth of the i-th tool position, h e is the additional cutting depth added when the cutting distance is x, and k is the proportional coefficient of cutting force and cutting depth.

7. An ultra-precision cutting workpiece surface quality detection device, characterized in that: include: a roughness model construction module configured to obtain a roughness curve and peak-to-valley values ​​corresponding to a surface of an ultra-precision cut workpiece to be inspected, perform Fourier transform on the roughness curve, determine a frequency value of the roughness of the surface of the ultra-precision cut workpiece, and construct a workpiece surface roughness model based on the roughness curve and the frequency value; a cutting force determination module configured to input tool parameters, workpiece parameters, machining parameters, and the workpiece surface roughness model into a three-dimensional cutting finite element simulation model to determine the cutting forces in the transverse, longitudinal, and vertical directions of the ultra-precision cutting workpiece surface; The cutting width determination module is configured to determine a relationship between an actual cutting depth and a change in the machined surface depth based on a cutting force in a direction perpendicular to the surface of the ultra-precision cutting workpiece, and to determine the cutting width of the ultra-precision cutting workpiece and the change in the machined surface depth based on a workpiece surface quality detection model and the relationship between the actual cutting depth and the change in the machined surface depth, wherein the workpiece surface quality detection model is: ， Among them, R is the radius of the tool tip arc of the finishing tool, h0 is the theoretical cutting depth, d is the finishing cutting distance, h0 is the theoretical cutting depth, A is the average roughness of the machined surface, and the B value is determined by the f value calculated after the roughness curve is passed through FFT, and its size is , the C value is obtained by fitting the roughness curve of the machined surface obtained after characterization, x is the distance from the cutting starting point, θ i is the angle between the line connecting the i-th point on the tool tip arc and the midpoint of the chord corresponding to the arc and the horizontal direction, k is the proportional coefficient of cutting force and cutting depth, and the G function represents the change in depth of the machined surface. With load F t Functional relationship, y is the cutting width, z is the change in the depth of the machined surface; The quality detection module is configured to determine the machining quality of the ultra-precision cut workpiece to be detected according to the cutting width and the variation of the machined surface depth, so as to complete the quality detection of the ultra-precision cut workpiece.

8. An electronic device comprising a central processing unit and a memory, characterized in that: The central processing unit is configured to call and run a computer program stored in the memory to execute the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that It stores a computer program implemented according to the method described in any one of claims 1 to 6 in the form of computer-readable instructions, and when the computer program is called and executed by a computer, the steps included in the corresponding method are executed.

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