Performance Evaluation Test Platform and Method for Intermittent Boring / Milling Tools in Bimetallic Materials

Abstract

This invention proposes a performance evaluation and testing platform and method for intermittent boring / milling tools in bimetallic materials, belonging to the field of tool performance testing technology. It includes a spindle, a fixture, and a base. The fixture is mounted on the base and holds the workpiece to be machined. The machined surface of the workpiece is an arc surface with notches. A cutter head is located at the bottom of the spindle, and cutting inserts are mounted on the cutter head. The spindle drives the cutting inserts to rotate, simultaneously causing the inserts to feed towards the workpiece, achieving intermittent cutting of the arc surface. This invention targets intermittent cutting of holes in bimetallic workpieces, performing intermittent cutting of arc surfaces. By adjusting the workpiece's arc degree and the number of notches, the degree of intermittent cutting can be controlled, enabling the testing and evaluation of the tool's intermittent cutting performance.

Description

Technical Field

[0001] This invention belongs to the field of cutting tool performance testing technology, and particularly relates to a performance evaluation and testing platform and method for bimetallic interrupted boring / milling tools. Background Technology

[0002] Due to the implementation of green manufacturing projects and the continuous promotion of energy conservation and carbon reduction plans in key industrial sectors, solid dissimilar bimetallic materials have gained widespread attention in the automotive industry due to their advantages of lightweighting, sustainability, and low cost, showing promising application prospects. However, as shown in Figures 1(a) and 1(b), the localized differences in stress state at the cutting edge of bimetallic materials lead to severe tool wear / breakage and low tool life stability, posing a significant challenge to tool performance and process optimization. Due to the complex characteristics of parts and the integration of machining processes, interrupted cutting is increasingly being used in production practice. During interrupted cutting, the working environment of the tool is harsh, making it prone to chipping, spalling, cracking, and breakage. Consequently, under the same cutting conditions, the service life of interrupted cutting tools is far lower than that of continuous cutting tools, seriously affecting the improvement of enterprise production efficiency and the reduction of production costs. Therefore, how to improve the service life of tools used in interrupted cutting has become an urgent production practice problem to be solved.

[0003] The first step in improving the life of interrupted cutting tools is to establish a performance evaluation and testing platform for these tools. Current performance testing of interrupted cutting tools is often geared towards turning designs, which involve breaking the continuous circumferential surface of a bar stock to achieve intermittent contact between the cutting tool and the circumferential surface. While this method can achieve interrupted cutting, for hole-type features, the relative motion trajectory between the tool and the workpiece is completely different from that of turning an outer diameter. When machining hole-type parts, tool rotation is the primary motion, and the interaction force between the tool and the workpiece during the cutting process has a significant impact on the tool's dynamic balance.

[0004] Therefore, existing turning platform setup methods cannot be applied to the evaluation and testing of tool cutting performance under interrupted milling and interrupted boring conditions for hole-shaped workpieces. Currently, there is still a lack of methods for evaluating and testing the performance of interrupted cutting tools for hole-shaped workpieces. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this invention provides a performance evaluation and testing platform and method for bimetallic intermittent boring / milling tools. For bimetallic workpieces with intermittent cutting hole characteristics, intermittent cutting of arc surfaces is performed. The degree of intermittency is controlled by adjusting the workpiece arc degree and the number of notches, thereby realizing the testing and evaluation of the tool's intermittent cutting performance.

[0006] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0007] The first aspect of this invention provides a performance evaluation and testing platform for bimetallic interrupted boring / milling tools.

[0008] A bimetallic material intermittent boring / milling tool performance evaluation and testing platform includes a spindle, a fixture, and a base. The fixture is mounted on the base and holds the workpiece to be machined. The machined surface of the workpiece is an arc surface with notches. A cutter head is mounted at the bottom of the spindle, and a cutting insert is mounted on the cutter head. The spindle drives the cutting insert to rotate and simultaneously feeds the cutting insert toward the workpiece to achieve intermittent cutting of the arc surface.

[0009] Optionally, the base is also equipped with a force measuring system, which includes a piezoelectric force gauge, a charge amplifier, and a data acquisition unit. The piezoelectric force gauge is used to measure the pressure on the arc surface during intermittent cutting and convert the pressure into a voltage signal. The voltage signal is transmitted to the data acquisition card via the charge amplifier and then transmitted to the host computer for display of the cutting force.

[0010] Optionally, a temperature acquisition device is also included, which is aligned with the tip of the blade to measure the temperature of the cutting zone.

[0011] Optionally, the workpiece to be processed is made of bimetallic material, with the two layers of metal materials welded and fixed together.

[0012] Optionally, the number of the notches may be set to one or more.

[0013] The second aspect of this invention provides a method for evaluating the performance of bimetallic interrupted boring / milling tools.

[0014] A test method based on the bimetallic material interrupted boring / milling tool performance evaluation test platform described in the first aspect includes the following steps:

[0015] Determine the radius and number of notches of the surface to be machined on the workpiece, and control the degree of discontinuity;

[0016] Fix the workpiece to be processed on the fixture and build a bimetallic material interrupted boring / milling tool performance evaluation and testing platform;

[0017] Start the spindle and use the cutting tool to perform intermittent cutting on the workpiece to be processed;

[0018] Record the cutting force and cutting temperature during the cutting process;

[0019] After cutting, obtain the tool wear data, surface quality data, and metal removal rate.

[0020] A tool cutting performance evaluation model is established. The analytic hierarchy process (AHP) is used to determine the weights of each level and the ratio of the scheme level indicators to the target level. Grey relational analysis is used to convert the original data of each evaluation index of the workpiece into grey relational coefficients, calculate the weighted correlation degree, and comprehensively evaluate the tool cutting performance.

[0021] Optionally, the degree of discontinuity is determined by the number of discontinuities N in each rotation cycle, the number of discontinuities Nx per unit length, and the discontinuity rate D. l The three parameters represent:

[0022] N = x + 1

[0023]

[0024]

[0025] Wherein, the diameter of the arc surface of the workpiece to be processed is D w The angle is α, the number of notches is x, the included angle of each notch is β, and the rotational speed of the cutter head is n.

[0026] Optionally, the Analytic Hierarchy Process (AHP) can be used to determine the weights between each level and between the indicators of the alternative level and the target level, specifically as follows:

[0027] Establish a hierarchical analysis structure for the bimetallic workpiece processing evaluation system, and determine the indicators for the objective layer, criterion layer, and scheme layer.

[0028] Based on the importance of each indicator in the same layer relative to the indicator in the previous layer, a pairwise comparison and scoring is performed to construct a judgment matrix;

[0029] Perform a consistency check on the judgment matrix;

[0030] Determine the weights of each level and the weights of the scheme level indicators relative to the target level indicators.

[0031] Optionally, grey relational analysis can be used to transform the original data of each evaluation index of the workpiece into grey relational coefficients, specifically:

[0032] By utilizing the optimal values ​​of each evaluation indicator, a reference indicator sequence is determined;

[0033] Perform normalization processing on the original indicator values ​​within the reference indicator sequence;

[0034] The processed original index values ​​are correlated to obtain a correlation coefficient matrix.

[0035] Optionally, a weight matrix can be formed based on the weights of each level and the ratio of the scheme level indicators to the target level indicators;

[0036] Based on the correlation coefficient matrix and weight matrix, the weighted correlation degree between the scheme layer and the target layer is obtained;

[0037] The cutting performance of cutting tools is evaluated based on the weighted correlation degree.

[0038] The above one or more technical solutions have the following beneficial effects:

[0039] This invention provides a bimetallic material intermittent boring / milling tool performance evaluation and testing platform and method, which can perform intermittent cutting of arc surfaces for testing and evaluating the intermittent cutting performance of tools. It realizes the evaluation and testing of tool cutting performance under different degrees of interruption and the online measurement of cutting force, cutting temperature and the life of the indexable insert to be evaluated during the testing process. The process and method are simple and convenient, easy to install, reusable, effectively reduce the cost of tool performance testing, and allow for quick replacement of workpieces and their quantity. The clamping is safe and reliable.

[0040] The degree of discontinuity in this invention can be controlled by adjusting the workpiece radius and the number of notches. The degree of discontinuity can be represented by three parameters: the number of discontinuities in each rotation cycle, the number of discontinuities per unit length, and the discontinuity rate. Controlling the degree of discontinuity through these three parameters facilitates data collection under various discontinuity conditions.

[0041] This invention uses grey relational analysis and analytic hierarchy process (AHP) to establish a tool cutting performance evaluation model. AHP is used to determine the weights between each level and between the scheme level indicators and the target level. Grey relational analysis is then used to convert the original data of each evaluation indicator of the bimetallic workpiece into grey relational coefficients. Finally, the weights and grey relational coefficients obtained by the two methods are used to calculate the weighted correlation degree to comprehensively evaluate the tool cutting performance, resulting in more accurate results.

[0042] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0043] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0044] Figure 1(a) shows the usage status of bimetallic material cutting edges in the prior art.

[0045] Figure 1(b) shows the stress state at the cutting edge of a bimetallic material in the prior art.

[0046] Figure 2 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention.

[0047] Figure 3 This is a schematic diagram of the workpiece structure to be processed without notches according to the present invention.

[0048] Figure 4 This is a schematic diagram of the workpiece structure to be processed with a notch according to the present invention.

[0049] Figure 5 This is a schematic diagram of the workpiece structure to be processed with two notches according to the present invention.

[0050] Figure 6 This is a flowchart illustrating the principle of the hierarchical analysis method in Embodiment 2 of the present invention.

[0051] The attached diagram lists the components represented by each number as follows:

[0052] 1. Cutting tool, 2. Material A, 3. Material B, 4. Spindle, 5. Fixture, 6. Base, 7. Workpiece to be processed, 8. Notch, 9. Arc surface, 10. Tool head, 11. Insert, 12. Force measuring system, 13. Temperature acquisition device, 14. Bolt. Detailed Implementation

[0053] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0054] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0055] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0056] Example 1

[0057] This embodiment discloses a performance evaluation and testing platform for bimetallic interrupted boring / milling tools.

[0058] like Figure 2 As shown, the bimetallic material intermittent boring / milling tool performance evaluation and testing platform includes a spindle 4, a fixture 5, and a base 6. The fixture 5 is set on the base 6 and holds the workpiece 7 to be processed. The surface to be processed of the workpiece 7 is an arc surface 9 with a notch 8. A cutter head 10 is set at the bottom of the spindle 4, and a cutting tool 11 is set on the cutter head 10. The spindle 4 drives the cutting tool 11 to rotate and simultaneously drives the cutting tool 11 to feed towards the workpiece 7, realizing intermittent cutting of the arc surface 9.

[0059] This invention addresses the current limitation of intermittent cutting test devices in evaluating the performance of tools used in intermittent boring / milling. It provides a tool cutting performance evaluation test device for intermittent boring / milling, which can be applied to milling machines and machining centers.

[0060] The tool interrupted cutting performance evaluation and testing device of the present invention adopts the following technical solution:

[0061] This intermittent boring / milling tool cutting performance evaluation and testing device includes a workpiece with a specific shape, a tool system (including a tool holder, tool head 10, and inserts 11), a force measuring system 12, and an infrared temperature measuring system. The tool system is mounted on the spindle 4 via the tool holder; the force measuring system 12 consists of a piezoelectric force gauge, a charge amplifier, and a data acquisition unit, etc. The piezoelectric force gauge is fixed to the machine tool table by bolts 14; the infrared temperature measuring system consists of an infrared thermometer 13 and a computer processing terminal, which is mounted on the worktable or tripod during testing; the workpiece's machined surface is designed as an arc surface 9 to extract hole-type machining features, and the degree of discontinuity can be adjusted by changing the number of notches 8 and the size of the arc degree (see the calculation of the discontinuity degree index for details). The workpiece is mounted above the force gauge and fixed by a specific fixture 5.

[0062] The aforementioned tool interrupted cutting performance evaluation and testing device is applied to CNC milling machines or machining centers. The workpiece block is mounted on a force gauge on the machine tool's worktable using a fixture 5. The cutting insert 11 to be evaluated is mounted on a tool head 10, which is mounted on the machine tool spindle 4 via a tool holder. The cutting insert 11 moves with the rotation of the spindle 4 to achieve feed motion. The voltage signal measured by the piezoelectric force gauge is transmitted via cable to a charge amplifier, and then transmitted to a data acquisition card in the computer via a data acquisition unit. The data acquisition card converts the voltage signal into electronic data, which is displayed on the computer using cutting force testing software. An infrared thermometer 13 is positioned at the tool tip to achieve online measurement of the cutting zone temperature, suitable for evaluating the interrupted cutting performance of boring / milling tools.

[0063] This invention can perform intermittent cutting on the arc surface 9, and is used for testing and evaluating the intermittent cutting performance of cutting tools. It can realize the evaluation and testing of cutting performance of cutting tools under different degrees of interruption, and online measurement of cutting force, cutting temperature and the life of the indexable insert 11 to be evaluated during the testing process. The process and method are simple and convenient, easy to install, reusable, effectively reduce the cost of cutting tool performance testing, and allow for quick replacement of workpieces and their quantity. The clamping is safe and reliable.

[0064] This invention can be applied to both CNC milling machines and CNC machining centers, and has a wide range of applications. The application of the tool interrupted cutting performance evaluation and testing device of this invention on CNC milling machines is as follows: Figure 2As shown, the entire workpiece block is clamped onto the machine tool table by the clamping part of the special fixture 5, and the indexable insert 11 to be evaluated is mounted on the cutter head 10. The insert 11 achieves feed motion as the cutter head 10 rotates, and the piezoelectric force gauge moves simultaneously with the workpiece. The voltage signal measured by the piezoelectric force gauge is transmitted to the data acquisition card through the charge amplifier via the connecting wire. The data acquisition card converts the voltage signal into electronic data, which is displayed on the computer through cutting force testing software. The infrared thermometer 13 is aligned with the tool tip to realize online measurement of the temperature in the cutting zone.

[0065] The workpiece material of this invention is a bimetallic material, and the bimetallic characteristics of the workpiece are as follows: Figure 3 , Figure 4 , Figure 5 As shown, the number of notches 8 can be set as needed. In this embodiment, the upper layer of the workpiece is aluminum alloy, and the lower layer is cast iron. The two layers are joined by friction stir welding. Considering the special characteristics of the workpiece material and shape, this test platform uses a customized clamp 5 for clamping and fixing. The workpiece is fixed and installed by four locking bolts 14, ensuring reliable positioning, firm locking, and easy installation and replacement. The workpiece can be reused, avoiding the need to replace different clamps 5 and saving the material and cost of manufacturing the clamps 5.

[0066] The above-mentioned testing device can meet the requirements for evaluating the cutting performance of various workpiece materials with different degrees of discontinuity when boring / milling. With the help of a force gauge and an infrared thermometer 13, the cutting force and cutting temperature during the cutting process can be detected and output online. The tool wear and surface quality after cutting are measured by an ultra-depth-of-field optical microscope.

[0067] Example 2

[0068] This embodiment discloses a method for evaluating the performance of bimetallic interrupted boring / milling tools.

[0069] A test method for evaluating the performance of bimetallic interrupted boring / milling tools as described in Example 1 includes the following steps:

[0070] Determine the radius and number of notches of the surface to be machined on the workpiece, and control the degree of discontinuity;

[0071] Fix the workpiece to be processed on the fixture and build a bimetallic material interrupted boring / milling tool performance evaluation and testing platform;

[0072] Start the spindle and use the cutting tool to perform intermittent cutting on the workpiece to be processed;

[0073] Record the cutting force and cutting temperature during the cutting process;

[0074] After cutting, obtain the tool wear data, surface quality data, and metal removal rate.

[0075] A tool cutting performance evaluation model is established. The analytic hierarchy process (AHP) is used to determine the weights of each level and the ratio of the scheme level indicators to the target level. Grey relational analysis is used to convert the original data of each evaluation index of the workpiece into grey relational coefficients, calculate the weighted correlation degree, and comprehensively evaluate the tool cutting performance.

[0076] The degree of discontinuity can be controlled by adjusting the workpiece's radius and the number of notches. The process and method are simple and convenient, as detailed below:

[0077] The degree of discontinuity can be determined by the number of discontinuities N in each rotation cycle, the number of discontinuities Nx per unit length, and the discontinuity rate D. l Three parameters are used to represent this. The number of interruptions N per rotation cycle refers to the number of times the cutting edge participates in cutting within one revolution of the tool's cutting edge; the number of interruptions Nx per unit length is the ratio of the number of times the cutting edge participates in cutting within one revolution of the tool to the total length of the cutting path; and the interruption rate D... l It refers to the ratio of the length of the cutting path during one revolution of the tool when the cutting edge does not participate in cutting to the total length of the cutting path.

[0078] Assume the diameter is D t Two blades are symmetrically arranged at equal intervals along the circumference of the cutter head, and the diameter of the workpiece's arc surface is D. w The angle is α, there are x notches, the included angle of each notch is β, and the rotational speed of the cutter head is n. Figure 4 As shown, the corresponding degree of discontinuity at this time can be expressed as:

[0079] N = x + 1

[0080]

[0081]

[0082] This embodiment uses grey relational analysis and analytic hierarchy process (AHP) to establish a tool cutting performance evaluation model. AHP is used to determine the weights between each level and between the scheme level indicators and the target level. Grey relational analysis is then used to convert the original data of each evaluation indicator of the bimetallic workpiece into grey relational coefficients. Finally, the weighted correlation degree is calculated using the weights and grey relational coefficients obtained by the two methods to comprehensively evaluate the tool cutting performance.

[0083] (1) The principle of grey relational analysis

[0084] Professor Deng Julong of Huazhong University of Science and Technology formally proposed the grey system theory in 1982. This theory utilizes grey relational analysis to quantitatively analyze the correlation between two factors. Compared with other system analysis methods such as regression analysis, analysis of variance, and principal component analysis, grey relational analysis has significant advantages and can effectively avoid the shortcomings of other methods in the calculation process. Grey relational analysis is based on the idea of ​​the similarity of the geometric shapes of curves to determine the strength of the relationship. The closer the curves are, the greater the correlation between the sequences.

[0085] The basic calculation steps of grey relational analysis are roughly as follows:

[0086] Let X be the grey relational factor set, and X0∈X be the reference index sequence. i ∈X is the comparison index sequence, X i (k) represent X0 and X... i The value at point k. There are a total of m comparative evaluation index sequences, and each comparative evaluation index sequence has n evaluation indicators.

[0087] Step 1: Set the reference indicator sequence X0 = {X0(k)}

[0088] The reference index sequence element X0(k) consists of the optimal value of each evaluation index in the evaluation index system. Its value depends on the specific problem to be studied. The reference index sequence can be set according to the values ​​of each index corresponding to the best tool life, workpiece quality and processing efficiency obtained by experiment or formula. Alternatively, a target sequence can be set to make the final evaluation index set close to the ideal index sequence set.

[0089] Step 2: Standardization Processing

[0090] To eliminate the influence of different indicators and different units on the comparison between indicators, different normalization methods are adopted for different types of indicators to normalize them into numbers belonging to the interval (0, 1). The normalization formula is as follows:

[0091]

[0092] Where i = 1, 2, ..., m, k = 1, 2, ..., n.

[0093] Step 3: Find the initial value image or mean image of each sequence.

[0094]

[0095] Where i = 1, 2, ..., m.

[0096] Step 3: Calculate the difference between each comparison index series and the reference index series.

[0097] Δ i(k)=|X′0(k)-X′ i (k)|

[0098] Where i = 1, 2, ..., m, k = 1, 2, ..., n.

[0099] Step 4: Find the maximum and minimum values ​​of the difference between the sequences.

[0100] M = max i max k Δ i (k)

[0101] m = min i min k Δ i (k)

[0102] Where i = 1, 2, ..., m, k = 1, 2, ..., n.

[0103] Step 5: Calculate the correlation coefficient

[0104]

[0105] The resolution coefficient ζ∈(0,1) is generally adopted as ζ=0.5, i=1,2,…,m,k=1,2,…,n.

[0106] Step 6: Calculate the correlation degree

[0107] The correlation between each comparison index series and the reference index series is:

[0108]

[0109] Y 0i Y represents the degree of correlation between each comparison index sequence and the reference index sequence. 0i The larger the value, the greater the correlation between this comparison index sequence and the reference index sequence.

[0110] By zeroing out the starting point of each index sequence, we obtain the zeroed-out image of each sequence's starting point:

[0111] X 0 0(k) = X0(k) - X0(1)

[0112] X 0 i (k)=X i (k)-X i (1)

[0113] Then there is

[0114]

[0115]

[0116]

[0117] Make the gray absolute correlation degree as follows:

[0118]

[0119] If we initialize the index sequences X′0 and X′... i By performing the above calculation to determine the absolute correlation, we obtain X0 and X... i The relative correlation of the gray areas is:

[0120]

[0121] Taking both grey relational degrees into account, the resulting grey comprehensive relational degree is:

[0122] p 0i =α·ε 0i +(1-α)·r 0i (18)

[0123] The allocation coefficient α∈(0,1) can be adjusted as needed.

[0124] (2) The principle of the analytic hierarchy process

[0125] In the early 1970s, American operations researcher Saaty proposed the famous Analytic Hierarchy Process (AHP). AHP decomposes decision-related elements into levels such as objectives, criteria, and alternatives (as shown in Table 1).

[0126] Table 1. Levels of the Bimetallic Workpiece Machining Evaluation System

[0127] Target layer Tool life, workpiece quality, machining efficiency Criterion layer Cutting temperature, cutting force, tool wear, surface quality, metal removal rate Solution layer Cutting speed, feed rate, depth of cut, depth of cut, interruption degree

[0128] Decision-making follows a process of decomposition, comparison, judgment, and synthesis. The impact of each factor on the outcome is digitized, and fuzzy numbers are used to represent the influence coefficient of each factor. The specific calculation steps are as follows: Figure 6 As shown.

[0129] Based on practical production experience, the primary evaluation indicators for roughing tools are cutting temperature, cutting force, flank wear, and metal removal rate. For finishing tools, the primary evaluation indicators are cutting temperature, cutting force, flank wear, and machining quality. Simultaneously, the two secondary evaluation indicators for machining quality (the primary evaluation indicator for finishing) – surface roughness and dimensional error – are considered equally important, and their weights are clearly ω1 = ω2. The final weights for each evaluation indicator are shown in Table 2.

[0130] Table 2 Weight values ​​of evaluation indicators

[0131]

[0132]

[0133] The specific steps of the tool performance evaluation model in this embodiment are as follows:

[0134] (1) Tool performance evaluation model

[0135] 1. The original data and the reference evaluation index sequence are combined to form the following evaluation matrix:

[0136]

[0137] As we know from the previous analysis, for roughing tools, n = 4; for finishing tools, n = 5.

[0138] 2. Standardized processing

[0139] The evaluation matrix is ​​normalized using formula (4) to obtain the normalized evaluation matrix as follows:

[0140]

[0141] 3. Calculate the correlation coefficient

[0142] The correlation coefficient is calculated using formula (10), and the correlation coefficient matrix is ​​obtained.

[0143]

[0144] Among them, it is obvious that Y 00 (1) = Y 00 (2) = ... = Y 00 (n)=1

[0145] 4. Calculate the weighted correlation coefficient

[0146] Construct a weight matrix from the weights in Table 2.

[0147]

[0148] Where ω1+ω2+…+ω n =1 and ω i >0

[0149] The weighted correlation degree between the solution layer and the target layer is:

[0150]

[0151] Where, it is obvious that y0 = 1, compare y1 to y m The size of the value can indicate the merits and demerits of each machining scheme in maintaining tool performance.

[0152] (2) Tool performance evaluation model for special cases

[0153] When we need to control conditions such as cutting force or cutting temperature, that is, when the evaluation target becomes a certain evaluation index in the criterion layer, the analysis system at this time has only two layers of structure, and we can directly use grey relational analysis to obtain the correlation degree of the scheme with the evaluation target through formula (10) or (16), (17), (18). The greater the correlation degree calculated, the closer the corresponding scheme is to the target scheme.

[0154] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0155] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A test method for a bimetallic material interrupted boring / milling tool performance evaluation test platform, characterized in that, The bimetallic material intermittent boring / milling tool performance evaluation and testing platform includes a spindle, a fixture, and a base. The fixture is set on the base and holds the workpiece to be processed. The surface to be processed on the workpiece is an arc surface with a notch. A cutter head is set at the bottom of the spindle, and a cutting tool is set on the cutter head. The spindle drives the cutting tool to rotate and simultaneously drives the cutting tool to feed towards the workpiece to achieve intermittent cutting of the arc surface. The testing method includes the following steps: Determine the radius and number of notches of the surface to be machined on the workpiece, and control the degree of discontinuity; Fix the workpiece to be processed on the fixture and build a bimetallic material interrupted boring / milling tool performance evaluation and testing platform; Start the spindle and use the cutting tool to perform intermittent cutting on the workpiece to be processed; Record the cutting force and cutting temperature during the cutting process; After cutting, obtain the tool wear data, surface quality data, and metal removal rate. A tool cutting performance evaluation model is established. The analytic hierarchy process (AHP) is used to determine the weights of each level and the ratio of the scheme level indicators to the target level. Grey relational analysis is used to convert the original data of each evaluation index of the workpiece into grey relational coefficients, calculate the weighted correlation degree, and comprehensively evaluate the tool cutting performance.

2. The test method for a bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, The bimetallic material intermittent boring / milling tool performance evaluation and testing platform used in this system also includes a force measurement system on the base. The force measurement system includes a piezoelectric force gauge, a charge amplifier, and a data acquisition unit. The piezoelectric force gauge is used to measure the pressure on the arc surface during intermittent cutting and converts the pressure into a voltage signal. The voltage signal is then transmitted to the data acquisition card via the charge amplifier and transmitted to the host computer for display of the cutting force.

3. The test method for a bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, The bimetallic material interrupted boring / milling tool performance evaluation and testing platform also includes a temperature acquisition device, which is aligned with the tool tip to measure the temperature of the cutting zone.

4. The test method for a bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, The bimetallic material interrupted boring / milling tool performance evaluation and testing platform used in this project is made of bimetallic material, with the two layers of metal materials welded and fixed together.

5. The test method for a bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, The bimetallic material interrupted boring / milling tool performance evaluation test platform used therein has one or more notches.

6. The test method for the bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, The degree of discontinuity is represented by three parameters: the number of discontinuities N in each rotation cycle, the number of discontinuities Nx per unit length, and the discontinuity rate Dl. The workpiece to be processed has a circular arc surface with diameter Dw and angle α, and x notches, with each notch having an included angle of α. The rotational speed of the cutter head is n.

7. The test method for the bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, The Analytic Hierarchy Process (AHP) is used to determine the weights between each level and the weights of the indicators at the alternative level relative to the target level, specifically as follows: Establish a hierarchical analysis structure for the bimetallic workpiece processing evaluation system, and determine the indicators for the objective layer, criterion layer, and scheme layer. Based on the importance of each indicator in the same layer relative to the indicator in the previous layer, a pairwise comparison and scoring is performed to construct a judgment matrix; Perform a consistency check on the judgment matrix; Determine the weights of each level and the weights of the scheme level indicators relative to the target level indicators.

8. The test method for the bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that, Grey relational analysis is used to transform the original data of each evaluation index of the workpiece into grey relational coefficients, specifically: By utilizing the optimal values ​​of each evaluation indicator, a reference indicator sequence is determined; Perform normalization processing on the original indicator values ​​within the reference indicator sequence; The processed original index values ​​are correlated to obtain a correlation coefficient matrix.

9. The test method for the bimetallic material interrupted boring / milling tool performance evaluation test platform as described in claim 1, characterized in that: A weight matrix is ​​formed based on the weights of each level and the ratio of the scheme level indicators to the target level indicators; Based on the correlation coefficient matrix and weight matrix, the weighted correlation degree between the scheme layer and the target layer is obtained; The cutting performance of cutting tools is evaluated based on the weighted correlation degree.

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