A method for calculating cutting force of wire cutting considering wire bow

Abstract

A method for calculating the cutting force of wire cutting considering the wire bow includes the following steps: establishing a theoretical mathematical model for calculating the cutting force in the wire cutting process; based on different settings of the wire cutting machine, the wire saw cuts the material, and multiple sets of cutting force experimental data are obtained respectively; based on any set of experimental data in the multiple sets of cutting force experimental data, combining the cutting force model when the wire bow is stable and the wire bow related parameter formula, the normal material coefficient and the tangential material coefficient are obtained; based on the normal material coefficient and the tangential material coefficient, combining the theoretical mathematical model of the cutting force, the material coefficient k is obtained p , and then the cutting force mathematical model of the material coefficient is obtained; according to the cutting force mathematical model of the material coefficient, the real-time cutting force under different settings is obtained. This method can provide an effective theoretical calculation basis in the wire cutting process, so as to facilitate the selection of the wire cutting path speed and the feed speed during processing and improve the slicing quality.

Description

Technical Field

[0001] The invention relates to the field of wire cutting, and in particular to a method for calculating the cutting force of wire cutting. Background Art

[0002] Nowadays, hard and brittle crystal materials have been widely used in all walks of life. Diamond wire cutting is usually used in the processing of hard and brittle materials. The wire cutting process can be divided into multi-wire cutting and single-wire cutting according to the number of slices, and can be divided into fixed abrasive and floating abrasive according to the abrasive. Due to the high efficiency of multi-wire cutting, multi-wire cutting is mostly used in actual industrial production and processing.

[0003] During the wire cutting process, the diamond wire will be subjected to the cutting force, which will produce a wire bow phenomenon, resulting in a nonlinear change in the cutting force. When the wire bow is formed, the cutting force will increase nonlinearly with the change of the wire bow. After the wire bow is stable, the cutting force also tends to be stable. Due to the uncertainty of the change of the wire bow, the theoretical calculation of the cutting force is very complicated. Therefore, it is necessary to invent a method that can effectively and conveniently calculate the wire cutting cutting force during the cutting process. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a technical solution adopted by the present invention: a method for calculating the cutting force of wire cutting considering the wire bow, comprising the following steps:

[0005] Establish a theoretical mathematical model for calculating cutting forces during wire cutting;

[0006] Based on the wire saw cutting the material under different settings of the wire cutting machine, multiple sets of cutting force experimental data were obtained;

[0007] Based on any one of the multiple cutting force experimental data, combined with the cutting force model when the wire bow is stable and the wire bow related parameter formula, the normal material coefficient and the tangential material coefficient are obtained;

[0008] Based on the normal material coefficient and the tangential material coefficient, combined with the cutting force theory mathematical model, the material coefficient k is obtained. p , and then obtain the cutting force mathematical model of the material coefficient;

[0009] According to the cutting force mathematical model of the material coefficient, the real-time cutting force under different settings is obtained.

[0010] Furthermore: the expression of the cutting force theoretical mathematical model is as follows:

[0011]

[0012] In the formula, v fRepresents the feed rate in mm / h, d m represents the diameter of the diamond wire in mm, l represents the material width in mm, L represents the span of the diamond wire in mm, v c Represents the routing speed in m / s, k p Represents the Preston coefficient, in μm 2 / N, F represents the wire tension, the unit is N, E represents the elastic modulus of the diamond wire, the unit is MPa, I represents the moment of inertia of the diamond wire, the unit is m 4 , t is the cutting time, unit is s, K 1 is the normal material coefficient, K 2 is the tangential material coefficient, Fn represents the normal cutting force, the unit is N, and Ft represents the tangential cutting force, the unit is N.

[0013] Further: the expression of the cutting force model when the line bow is stable is as follows:

[0014]

[0015] Where: α 3 is the arc angle of the tight side of the line bow, α 4 is the arc turning angle of the loose edge of the line bow, R is the radius of the fitting arc, v f Represents the feed rate in mm / h, d m Represents the diameter of the diamond wire in mm, K 1 is the normal material coefficient, K 2 is the tangential material coefficient, Fn represents the normal cutting force in N, Ft represents the tangential cutting force in N, and r is the radius of the diamond wire in mm.

[0016] Further: the line bow related parameter formula includes a line bow arc expression and a line bow deflection expression; the line bow arc expression is as follows:

[0017]

[0018] Where: v f represents the feed speed in mm / h, r represents the diamond wire radius in mm, l represents the material width in mm, L represents the diamond wire span in mm, v c Represents the wire speed in m / s, F represents the wire tension in N, E represents the elastic modulus of the diamond wire in MPa, and I represents the moment of inertia of the diamond wire in m 4 .

[0019] Further: the line bow deflection expression is as follows:

[0020]

[0021] Where: w 1 is the tight side deflection of the line bow, w 2 It is the loose side deflection of the line bow.

[0022] Furthermore: the wire saw used for cutting is a diamond abrasive coated wire saw or a steel wire saw.

[0023] Furthermore, the different settings are: only one of the three variables of the wire speed, the feed speed and the wire tension changes at the same time, and the other two variables remain unchanged.

[0024] A computer-readable storage medium stores a computer program, wherein when the computer program is run, the method for calculating the wire cutting cutting force taking into account the wire bow is executed.

[0025] The method for calculating the cutting force of wire cutting considering the wire bow provided by the present invention has the following advantages:

[0026] This method can provide an effective theoretical calculation basis for the online cutting process, so as to facilitate the selection of the wire cutting speed and feed speed during processing and improve the slice quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 It is a specific flow chart of a method for calculating cutting force in a wire cutting process in a specific implementation of the present invention;

[0029] Figure 2 The experimental data graph when the original tension is 20N and not fitted;

[0030] Figure 3 The result graph is obtained after fitting the experimental data with the original tension of 20N;

[0031] Figure 4 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the wire tension is 20N;

[0032] Figure 5 This is a comparison chart between the experimental value and the theoretical value of the tangential cutting force when the line tension is 20N;

[0033] Figure 6This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the wire tension is 25N;

[0034] Figure 7 This is a comparison chart between the experimental and theoretical values ​​of the tangential cutting force when the line tension is 25N;

[0035] Figure 8 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line tension is 30N;

[0036] Fig. 9 This is a comparison chart between the experimental value and the theoretical value of the tangential cutting force when the line tension is 30N;

[0037] Fig.10 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the feed speed is 40 mm / h;

[0038] Fig.11 This is a comparison chart between the experimental and theoretical values ​​of tangential cutting force when the feed speed is 40 mm / h;

[0039] Fig.12 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the feed speed is 50 mm / h;

[0040] Fig.13 This is a comparison chart between the experimental and theoretical values ​​of tangential cutting force when the feed speed is 50 mm / h;

[0041] Fig.14 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the feed speed is 60 mm / h;

[0042] Fig.15 This is a comparison chart between the experimental and theoretical values ​​of tangential cutting force when the feed speed is 60 mm / h;

[0043] Fig.16 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line speed is 12.5m / s;

[0044] Fig.17 This is a comparison chart between the experimental and theoretical values ​​of the tangential cutting force when the line speed is 12.5 m / s;

[0045] Fig.18 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line speed is 15m / s;

[0046] Fig.19 This is a comparison chart between the experimental and theoretical values ​​of the tangential cutting force when the line speed is 15m / s;

[0047] Fig. 20 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line speed is 17.5m / s;

[0048] Fig.21 This is a comparison chart of the experimental and theoretical values ​​of the tangential cutting force when the wire speed is 17.5m / s. DETAILED DESCRIPTION

[0049] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0050] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0052] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0053] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0054] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0055] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0056] Figure 1 It is a specific flow chart of a method for calculating cutting force in a wire cutting process in a specific implementation of the present invention;

[0057] A method for calculating the cutting force of wire cutting considering wire bow, comprising the following steps

[0058] S1: Establish a theoretical mathematical model for calculating cutting force during wire cutting;

[0059] The expression of the cutting force theoretical mathematical model is as follows:

[0060]

[0061] In the formula, v f Represents the feed rate in mm / h, d mrepresents the diameter of the diamond wire in mm, l represents the material width in mm, L represents the span of the diamond wire in mm, v c Represents the routing speed in m / s, k p Represents the Preston coefficient, in μm 2 / N, F represents the wire tension, the unit is N, E represents the elastic modulus of the diamond wire, the unit is MPa, I represents the moment of inertia of the diamond wire, the unit is m 4 , t is the cutting time, unit is s, K 1 is the normal material coefficient, K 2 is the tangential material coefficient; Fn represents the normal cutting force, in N, and Ft represents the tangential cutting force, in N;

[0062] S2: Based on the wire saw cutting the material under different settings of the wire cutting machine, multiple sets of cutting force experimental data are obtained respectively;

[0063] The wire saw cutting experiment process on the wire cutting machine with different wire speeds, feed speeds, and wire tensions was established, and the experiments were carried out with different wire speeds, feed speeds, and wire tensions.

[0064] The different settings are: only one variable among the three variables of wire speed, feed speed and wire tension changes at the same time, and the other two variables remain unchanged; that is, the wire speed changes, and the feed speed and wire tension remain unchanged;

[0065] The feed speed changes, while the wire speed and wire tension remain unchanged;

[0066] The wire tension changes, while the wire speed and feed speed remain unchanged; in the experiment, sensors are used to collect cutting force data at every moment when the multi-wire cutting machine is working.

[0067] S3: Based on any one set of experimental data from multiple sets of cutting force experimental data, the experimental data Fn and Ft are obtained by applying them to formula (1); the normal material coefficient and the tangential material coefficient are obtained by combining the cutting force model when the wire bow is stable and the wire bow related parameter formula;

[0068] Further: the expression of the cutting force model when the line bow is stable is as follows:

[0069]

[0070] Where: α 3 is the arc angle of the tight side of the line bow, α 4 is the arc turning angle of the loose edge of the line bow, R is the radius of the fitting arc, v f Represents the feed rate in mm / h, d m Represents the diameter of the diamond wire in mm, K 1 is the normal material coefficient, K2 is the tangential material coefficient. Fn represents the normal cutting force in N, Ft represents the tangential cutting force in N, r is the diamond wire radius in mm,

[0071] Further: the line bow related parameter formula includes a line bow arc expression and a line bow deflection expression; the line bow arc expression is as follows:

[0072]

[0073] Where: v f represents the feed speed in mm / h, r represents the diamond wire radius in mm, l represents the material width in mm, L represents the diamond wire span in mm, v c Represents the wire speed in m / s, F represents the wire tension in N, E represents the elastic modulus of the diamond wire in MPa, and I represents the moment of inertia of the diamond wire in m 4 .

[0074] Further: the line bow deflection expression is as follows:

[0075]

[0076] Where: w 1 is the tight side deflection of the line bow, w 2 is the loose side deflection of the line bow,

[0077] S4: Based on the normal material coefficient and the tangential material coefficient, combined with the cutting force theory mathematical model (i.e., substituting the normal material coefficient and the tangential material coefficient into formula (1)), the material coefficient k is obtained. p , and then obtain the cutting force mathematical model of the material coefficient;

[0078] S5: According to the cutting force mathematical model of the material coefficient, the real-time cutting force under different settings is obtained.

[0079] S1, S2, S3, S4, and S5 are performed sequentially;

[0080] The K1, K2, and kp parameters of the same material are the same;

[0081] Furthermore: the wire saw used for cutting is a diamond abrasive coated wire saw or a steel wire saw.

[0082] The parameters in the cutting force theory mathematical model described this time are determined by combining the specific material to be cut, the specific parameter range and specifications of the multi-wire cutting machine, and the wire saw parameters.

[0083] In step S2, a wire saw cutting process of a material on a wire cutting machine with different wire speeds, feed speeds and wire tensions is established, and experiments are conducted on multiple wire cutting machines respectively. During the experiment, a sensor is used to measure the magnitude of the cutting force during the experiment.

[0084] The wire speed, feed speed, and wire tension used in the theoretical calculation in step S5 are the same as those used in the experimental process.

[0085] A computer-readable storage medium stores a computer program, wherein when the computer program is run, the method for calculating the wire cutting cutting force taking into account the wire bow is executed.

[0086] Determine the values ​​of wire tension, wire speed, and feed speed obtained in different experiments. The values ​​selected in this experiment are shown in Table 1 below.

[0087] Table 1 Parameters selected for this experiment

[0088] Line tension (N) Wiring speed (m / s) Feed speed (mm / h) 20 40 12.5 35 50 15 30 60 175

[0089] The original experimental data are as follows Figure 2 As shown, the experimental data is imported into MATLAB, and programming is performed in MATLAB to fit the experimental data into a smooth curve. Figure 3 As shown;

[0090] Formula (1) was programmed in MATLAB to calculate different wire tensions, wire speeds, and feed speeds to obtain the theoretical calculation value of the cutting force.

[0091] The experimental data fitting results were compared with the theoretical calculation results.

[0092] Figure 4 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the wire tension is 20N;

[0093] Figure 5 This is a comparison chart between the experimental value and the theoretical value of the tangential cutting force when the line tension is 20N;

[0094] Figure 6 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the wire tension is 25N;

[0095] Figure 7 This is a comparison chart between the experimental and theoretical values ​​of the tangential cutting force when the line tension is 25N;

[0096] Figure 8 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line tension is 30N;

[0097] Fig. 9This is a comparison chart between the experimental value and the theoretical value of the tangential cutting force when the line tension is 30N;

[0098] Fig.10 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the feed speed is 40 mm / h;

[0099] Fig.11 This is a comparison chart between the experimental and theoretical values ​​of tangential cutting force when the feed speed is 40 mm / h;

[0100] Fig.12 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the feed speed is 50 mm / h;

[0101] Fig.13 This is a comparison chart between the experimental and theoretical values ​​of tangential cutting force when the feed speed is 50 mm / h;

[0102] Fig.14 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the feed speed is 60 mm / h;

[0103] Fig.15 This is a comparison chart between the experimental and theoretical values ​​of tangential cutting force when the feed speed is 60 mm / h;

[0104] Fig.16 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line speed is 12.5m / s;

[0105] Fig.17 This is a comparison chart between the experimental and theoretical values ​​of the tangential cutting force when the line speed is 12.5 m / s;

[0106] Fig.18 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line speed is 15m / s;

[0107] Fig.19 This is a comparison chart between the experimental and theoretical values ​​of the tangential cutting force when the line speed is 15m / s;

[0108] Fig. 20 This is a comparison chart between the experimental value and the theoretical value of the normal cutting force when the line speed is 17.5m / s;

[0109] Fig.21 This is a comparison chart of the experimental and theoretical values ​​of the tangential cutting force when the wire speed is 17.5m / s.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating wire cutting cutting force considering wire bow, Features: The following steps are included to establish a theoretical mathematical model for calculating cutting force during wire cutting processing; The expression of the cutting force theoretical mathematical model is as follows: In the formula, v f Represents the feed rate in mm / h, d m represents the diameter of the diamond wire in mm, l represents the material width in mm, L represents the span of the diamond wire in mm, v c Represents the routing speed in m / s, k p Represents the Preston coefficient, in μm 2 / N, F represents the wire tension, the unit is N, E represents the elastic modulus of the diamond wire, the unit is MPa, I represents the moment of inertia of the diamond wire, the unit is m 4 , t is the cutting time, unit is s, K 1 is the normal material coefficient, K 2 is the tangential material coefficient, Fn represents the normal cutting force, the unit is N, and Ft represents the tangential cutting force, the unit is N; Based on the wire saw cutting the material under different settings of the wire cutting machine, multiple sets of cutting force experimental data were obtained; Based on any one of the multiple cutting force experimental data, combined with the cutting force model when the wire bow is stable and the wire bow related parameter formula, the normal material coefficient and the tangential material coefficient are obtained; The expression of the cutting force model when the line bow is stable is as follows: Where: α 3 is the arc angle of the tight side of the line bow, α 4 is the arc turning angle of the loose edge of the line bow, R is the radius of the fitting arc, v f Represents the feed rate in mm / h, d m Represents the diameter of the diamond wire in mm, K 1 is the normal material coefficient, K 2 is the tangential material coefficient, Fn represents the normal cutting force in N, Ft represents the tangential cutting force in N, r is the diamond wire radius in mm; The line bow related parameter formula includes the line bow arc expression and the line bow deflection expression; the line bow arc expression is as follows: Where: v f represents the feed speed in mm / h, r represents the diamond wire radius in mm, l represents the material width in mm, L represents the diamond wire span in mm, v c Represents the wire speed in m / s, F represents the wire tension in N, E represents the elastic modulus of the diamond wire in MPa, and I represents the moment of inertia of the diamond wire in m 4 ; Based on the normal material coefficient and the tangential material coefficient, combined with the cutting force theory mathematical model, the material coefficient k is obtained. p , and then obtain the cutting force mathematical model of the material coefficient; According to the cutting force mathematical model of the material coefficient, the real-time cutting force under different settings is obtained.

2. A method for calculating the cutting force of wire cutting considering wire bow according to claim 1, Features: The line bow deflection expression is as follows: Where: w 1 is the tight side deflection of the line bow, w 2 It is the loose side deflection of the line bow.

3. A method for calculating the cutting force of wire cutting considering wire bow according to claim 1, Features: The wire saw used for the cutting is a diamond abrasive coated wire saw or a steel wire saw.

4. A method for calculating the cutting force of wire cutting considering wire bow according to claim 1, Features: The different settings are: only one variable among the three variables of wire speed, feed speed and wire tension changes at the same time, and the other two variables remain unchanged.

5. A computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, in, When the computer program is running, the method for calculating the wire cutting cutting force taking into account the wire bow as described in any one of claims 1 to 4 is executed.

Images