阅读说明：本技术 车削大螺距螺纹减振刀具的设计方法 (Design method of vibration reduction cutter for turning large-pitch threads ) 是由 李哲 王少宇 王福成 丛伟琦 罗明明 田盛 赵建青 于 2020-11-27 设计创作，主要内容包括：本发明公开了一种车削大螺距螺纹减振刀具的设计方法,包括刀片结构设计、刀杆减振设计、螺钉连接偏心距及配套切削参数的求取方法。对刀片后角、刃口半径、主轴转速及轴向进刀量四个因素进行正交仿真,提取力和温度；以力、温度和加工效率为优化目标,通过遗传算法求取最优的后角、刃口半径及切削参数。减振刀杆采用圆形空腔添加减振元件的结构,空腔直径与长度以挠度作为评价目标通过ansys求得,利用所建立的减振元件动力学模型求取质量块、弹簧和阻尼；选用S型连接方式,在最佳预紧力作用下,以刀杆变形作为考核指标通过ansys求得偏心距；由上述方法设计制备的减振刀具及优化的切削参数,可有效降低车削过程中的切削振动,提高工件表面质量。(The invention discloses a design method of a large-pitch thread turning vibration reduction cutter, which comprises a blade structure design, a cutter bar vibration reduction design, a screw connection eccentricity and a method for solving matched cutting parameters. Orthogonal simulation is carried out on four factors of the blade back angle, the cutting edge radius, the spindle rotating speed and the axial feed amount, and force and temperature are extracted; and (3) taking the force, the temperature and the machining efficiency as optimization targets, and solving the optimal back angle, the optimal cutting edge radius and optimal cutting parameters through a genetic algorithm. The vibration reduction cutter bar adopts a structure that a circular cavity is added with a vibration reduction element, the diameter and the length of the cavity are obtained by ansys with deflection as an evaluation target, and a mass block, a spring and damping are obtained by utilizing an established vibration reduction element dynamic model; an S-shaped connection mode is selected, and under the action of the optimal pretightening force, the eccentricity is obtained through ansys by taking the deformation of the cutter bar as an examination index; the vibration reduction tool designed and prepared by the method and the optimized cutting parameters can effectively reduce the cutting vibration in the turning process and improve the surface quality of the workpiece.)

1. The design method of the vibration reduction cutter for turning the large-pitch threads is characterized in that the design method of the vibration reduction cutter for turning the large-pitch threads is provided for effectively reducing vibration in the process of turning the large-pitch threads, and comprises the following steps:

the method comprises the steps of firstly, providing a blade angle constraint condition, namely a blade angle design range, carrying out four-factor orthogonal simulation on a blade material selected by adopting finite element simulation software according to the structural characteristics of a helix angle of a turned large-pitch threaded workpiece and a cutter vibration equation, extracting cutting force and cutting temperature, establishing a blade empirical model by taking the rotation speed of a main shaft, the axial feed, the cutter relief angle and the blade radius as optimization targets, carrying out multivariate linear regression analysis on the orthogonal simulation cutting force and cutting temperature by utilizing a least square method to solve the cutting force and cutting temperature optimization model coefficients, and converting an optimization target function with small cutting force, small cutting temperature and large material removal rate into a single-target optimization model in a linear weighting mode through the cutter structure and cutting parameter boundary conditions, using MATLAB to solve the optimization model to obtain the optimal blade back angle, cutting edge radius and cutting parameters;

secondly, the vibration reduction cutter bar adopts a structure that a circular cavity is added with a vibration reduction element, the cutter bar is converted into a cantilever beam structure, ansys is utilized to calculate the deflection of the vibration reduction cutter bar, the diameter and the length of the cavity of the vibration reduction cutter bar are determined, and the verification of the harmonic response vibration amplitude of the cutter bar is carried out; solving a mass block, a spring and damping in the vibration damping element through the established vibration damping element dynamic model, and carrying out vibration harmonic response amplitude finite element simulation verification on the mass block, the spring and the damping;

selecting S-shaped screws for connection, and solving the optimal screw pretightening force by taking the screw deformation, the screw equivalent stress, the screw shearing stress, the cutter bar deformation and the blade deformation as optimization targets through finite element simulation in the pretightening force range not exceeding 80% of the yield limit of the screw material; the eccentricity is calculated by simulation by taking the stress deformation of the cutter bar as a measurement index.

2. The design method for the vibration damping tool for turning large-pitch threads as defined in claim 1, wherein the optimization model of cutting force and cutting temperature can be verified for reliability by significance test through analysis of variance of simulation data, if significant, the multi-objective optimization model is indicated to be effective, and if not significant, the multi-objective optimization model is re-analyzed until the analysis of variance reaches significance.

3. The design method of the turning large-pitch thread vibration damping cutter according to claim 1, characterized in that the tool bar harmonic response simulation verification is carried out on the different diameters and the lengths of the tool bar vibration damping circular cavity by adopting ANSYS, if the harmonic response amplitude reaches the minimum, the calculated diameter and the length of the vibration damping cavity are considered to meet the vibration damping effect, and if the harmonic response amplitude does not reach the minimum, the cavity diameter and the length are designed by carrying out deflection calculation again until the tool bar harmonic response amplitude is met to the minimum; after the vibration damping element is designed, carrying out harmonic response simulation comparative analysis on the damping cutter bar and the solid cutter bar through finite element simulation, and if the harmonic response amplitude of the damping cutter bar reaches the minimum value, considering that the vibration damping element meets the vibration damping effect; if the damping cutter bar does not reach the minimum, the damping element is optimized again until the damping effect is met.

Technical Field

The invention relates to a design method of a vibration reduction cutter, in particular to a design method of a vibration reduction cutter for turning large-pitch threads, and belongs to the field of machining.

Background

The large-pitch threaded workpiece is widely applied to mechanical equipment such as heavy horizontal lathes, heavy boring and milling machines and the like. The large-pitch thread workpiece has the functions of connection, power transmission and the like, and is an important component for ensuring the stability of equipment. The large-pitch thread workpiece has long axial length and poor rigidity, so that the vibration of a process system is severe, the abrasion of a cutter is aggravated, and the long-stroke high-quality machining of a large-pitch thread surface cannot be finished. The large-pitch thread cutting tool is a formed tool designed and developed according to factors such as pitch, helix angle and the like, and the vibration of the large-pitch thread cutting tool in the cutting process causes the wear condition of the tool and the deterioration condition of the processing quality of a workpiece caused by the wear condition.

In the metal cutting process, different geometrical parameters, structural parameters of the cutting edge and vibration reduction parameters of the cutter bar have different influences on cutting force, cutting heat and cutting vibration generated in the cutting process. Meanwhile, the geometric parameters, the cutting edge structure parameters and the cutter bar vibration reduction parameters of the cutter affect the abrasion of the cutter to a certain extent, and have important influence significance on the service life of the cutter.

Therefore, aiming at the problems that the large vibration generated in the large-pitch thread turning process causes poor surface quality of a workpiece and serious damage of a cutter, the design method for the large-pitch thread turning vibration reduction cutter comprises a blade structure design method, a cutter bar vibration reduction design method, a screw connection eccentricity calculation method and a cutting parameter calculation method matched with the cutter.

Disclosure of Invention

The invention provides a design method of a vibration reduction cutter for turning large-pitch threads, which can design a complete vibration reduction cutter by providing a blade structure design method, a cutter bar vibration reduction design method, a screw connection eccentricity calculation method and a matched optimal cutting parameter calculation method, effectively reduce cutting vibration in the process of turning large-pitch threads, and improve the service life of the cutter and the surface quality of a workpiece.

The invention relates to a design method of a vibration reduction cutter for turning large-pitch threads, which comprises the following steps of:

the method comprises the steps of firstly, providing a blade angle constraint condition, namely a blade angle design range, carrying out four-factor orthogonal simulation on a blade material selected by adopting finite element simulation software according to the structural characteristics of a helix angle of a turned large-pitch threaded workpiece and a cutter vibration equation, extracting cutting force and cutting temperature, establishing a blade empirical model by taking the rotation speed of a main shaft, the axial feed, the cutter relief angle and the blade radius as optimization problem independent variables, carrying out multivariate linear regression analysis on the orthogonal simulation cutting force and cutting temperature by utilizing a least square method to solve the cutting force and cutting temperature optimization model coefficients, and converting an optimization objective function with small cutting force, small cutting temperature and large material removal rate into a single-target optimization model in a linear weighting mode through the boundary conditions of a cutter structure and cutting parameters, using MATLAB to solve the optimization model to obtain the optimal blade back angle, cutting edge radius and cutting parameters;

further: the cutting edge forms of the turning cutter are mainly classified into four types, namely a sharp edge, a chamfered edge, a vibration-damping edge and a blunt round edge, the four edge-shaped structural characteristics are contrasted according to the structural characteristics of large thread pitch, large back-draft and helix-rise angle, the chamfered edge and the blunt round edge are selected, ORDEFM is carried out on the chamfered edge and the blunt round edge with different chamfered angles, chamfered widths and blunt round radii, and the blunt round edge can obtain smaller cutting force and cutting temperature, so that the blunt round edge is selected as the cutting edge form of the blade; the reliability of the multi-target parameter optimization model of the cutting force and the cutting temperature can be verified through significance test of variance analysis of simulation data, if the reliability is significant, the multi-target parameter optimization model is effective, and if the reliability is not significant, the multi-target parameter optimization model is re-analyzed until the significance of the variance analysis is achieved;

secondly, the vibration reduction cutter bar adopts a structure that a circular cavity is added with a vibration reduction element, the cutter bar is converted into a cantilever beam structure, the diameter and the length of the cavity of the vibration reduction cutter bar are determined through calculating the deflection of the vibration reduction cutter bar, and then the verification of the harmonic response vibration amplitude of the cutter bar is carried out through finite element simulation; then, solving a mass block, a spring and damping in the vibration damping element through a dynamic model established by the vibration damping element, and carrying out vibration harmonic response amplitude finite element simulation verification on the vibration damping element after the design of the vibration damping element is finished;

further: carrying out cutter bar harmonic response simulation verification on different diameters and lengths of the cutter bar vibration reduction circular cavity by adopting ANSYS, if the harmonic response amplitude reaches the minimum, considering that the calculated diameter and length of the vibration reduction cavity meet the vibration reduction effect, and if the harmonic response amplitude does not reach the minimum, carrying out deflection calculation again to design the diameter and length of the cavity until the minimum harmonic response amplitude of the cutter bar is met; the dynamic model of the vibration damping element is established for solving the mass of the mass block, the elastic coefficient of the spring and the damping coefficient of the damping liquid so as to select materials, the mass block is connected with the cutter bar through the spring, and the damping liquid is positioned between the mass block and the cavity; after the vibration damping element is designed, carrying out harmonic response simulation comparative analysis on the damping cutter bar and the solid cutter bar through finite element simulation, and if the harmonic response amplitude of the damping cutter bar reaches the minimum value, considering that the vibration damping element meets the vibration damping effect; if the damping cutter bar does not reach the minimum, the damping element is optimized again until the damping effect is met;

step three, solving the connecting eccentricity of the screws, wherein only one clamping blade part of the S-type clamping mode is adopted, so that the clamping mode is simple and convenient, and the S-type screw clamping mode is selected; in the pretightening force range which does not exceed 80 percent of the yield limit of the screw material, the optimal screw pretightening force is obtained by taking the screw deformation, the screw equivalent stress, the screw shear stress, the cutter bar deformation and the blade deformation as optimization targets through finite element simulation; under the action of pretightening force, the eccentricity is calculated by ANSYS by taking the stress deformation of the cutter bar as a measurement index;

step four, the vibration reduction cutter is designed and prepared by combining the step one, the step two and the step three, optimized cutting parameters are adopted, and the effectiveness of the cutter structure parameters and the vibration reduction cutter is verified through analyzing cutting vibration, cutting force and cutting edge abrasion experimental results, so that the cutting force and vibration in the process of turning the large-pitch thread can be effectively reduced, the service life of the cutter is prolonged, and the surface quality of a workpiece is improved;

the invention has the advantages of

The scope of a vibration reduction cutter system is defined, a design method of a finish turning large-pitch thread vibration reduction cutter is provided, and a blade structure design method, a cutter bar vibration reduction design method and a screw connection eccentricity calculation method are carried out in consideration of the fact that vibration caused by cutting force and vibration caused by the cutter system are used as measurement standards. The cutter bar vibration reduction design comprises cutter bar structural design and vibration reduction element design, the screw connection eccentricity solving method comprises acquisition of screw pretightening force and eccentricity, and the design method can better obtain a vibration reduction cutter capable of effectively reducing vibration in the process of turning the large-pitch thread, so that application of the large-pitch thread turning vibration reduction technology is promoted.

Drawings

FIG. 1 flow chart of design method of vibration reduction tool for turning large-pitch threads

FIG. 2 damping tool bar dynamics model

FIG. 3 three-direction vibration acceleration value of cutter

Fig. 4 three-way cutting force of the tool

FIG. 5 front and rear cutting edge structural changes during turning

Detailed Description

For a further understanding of the present invention, reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The invention relates to a design method of a large-pitch thread turning vibration reduction cutter, which specifically comprises the following steps:

the design method of the vibration reduction cutter for turning the large-pitch threads takes the cutting temperature and the cutting force as the measurement standards, and the vibration reduction cutter capable of effectively reducing the vibration of the turning large-pitch threads is designed, and the design method comprises the following steps:

the method comprises the steps of firstly, providing a blade angle constraint condition, namely a blade angle design range, carrying out orthogonal simulation on four factors including a main shaft rotating speed and an axial feed amount on a rear angle, a cutting edge radius and cutting parameters of a hard alloy blade by adopting finite element simulation software according to the structural characteristics of a helix angle of a turned large-pitch threaded workpiece and a cutter vibration equation, extracting cutting force and cutting temperature, establishing a cutting edge empirical model by taking the main shaft rotating speed, the axial feed amount, a cutter rear angle and the cutting edge radius as optimization problem independent variables, carrying out multivariate linear regression analysis on the orthogonal simulation cutting force and the cutting temperature by utilizing a least square method to solve cutting force and cutting temperature optimization model coefficients, and converting an optimization target function with small cutting force, small cutting temperature and large material removal rate into a single-target optimization model in a linear weighting mode through the cutter structure and cutting parameter boundary conditions, using MATLAB to obtain the optimal blade back angle, cutting edge radius and cutting parameters of the optimized model;

further: the cutting edge shapes are mainly divided into four types, namely sharp edges, chamfered edges, vibration absorbing edges and blunt round edges, the structural characteristics of the four types of cutting edge shapes are contrasted according to the structural characteristics of large thread pitch, large back cutting load and helix angle, the form of the chamfered edges and the blunt round edges is selected, ORDEFM is carried out on the chamfered edges and the blunt round edges with different chamfer angles, chamfer widths and blunt round radii, and the blunt round edges are selected with the aim of smaller cutting force and cutting temperature; the reliability of the multi-target parameter optimization model of the cutting force and the cutting temperature can be verified through significance test of variance analysis of simulation data, if the reliability is significant, the multi-target parameter optimization model is effective, and if the reliability is not significant, the multi-target parameter optimization model is re-analyzed until the significance of the variance analysis is achieved;

the coarse pitch thread machining cutter is limited by the size of a cutter rod and the requirement of an actual machining process, and the structural parameter constraint relation of the cutter is as follows:

wherein H is the thread profile angle height, alpha is the thread profile angle, l₁Is the length of the right edge of the tool, /)₂Is the length of the left edge of the cutter.

The constraints of the structural parameters of the cutting portion of the tool are as follows:

ε_rl＝π-k_r；ε_rr＝k_rr (2)

in the formula of_rlIs a sharp angle of a left-edge knife, epsilon_rrIs a sharp angle of a right-edge knife, k_rlIs the left edge principal angle, k_rrIs the right edge principal declination.

When the large-pitch thread is turned, the following relations exist between the front angle and the rear angle of the actual left and right edges of the cutter and the helix angle:

in the formula, gamma_oelIs the left edge rake angle, gamma_oerIs the right edge rake angle, α_oelLeft edge relief angle, α_oerIs the back angle of the right edge,is the helix angle. Gamma ray_ol、γ_orMarking the left and right edge rake angles, alpha, for the tool_ol、α_orMarking left and right edge relief angles for a tool

The following relationship exists between the main deflection angle of the cutter and the tooth form angle:

wherein alpha is a tooth form angle.

The cutter material is made of hard alloy, the grade is YT15, the workpiece material is made of 45# steel, the grade is W18cr4v, the front angle of the cutter is 0 degree front angle, and a 4-factor 4 horizontal orthogonal test table is designed for the rear angle of the cutter, the radius of a cutting edge, the rotating speed and the axial feed amount.

TABLE 1 orthogonal experiment factor horizon

TABLE 2 orthogonal table of cutting force and cutting temperature

Empirical model with blunt round edge

Wherein F is cutting force, T is cutting temperature, Q is material removal rate, and C₁、C₂、C₃The cutting environment correction coefficients are n, f, alpha and R, the main shaft rotation speed, the axial feed amount, the cutter relief angle and the radius of the blunt round cutting edge are respectively₁、a₂、a₃、a₄、a₅Respectively, are indices of factors affecting the cutting temperature of the cutting force.

The reliability of the multi-target parameter optimization model of the cutting force and the cutting temperature can be verified through significance test of variance analysis of simulation data, if the reliability is significant, the multi-target parameter optimization model is effective, and if the reliability is not significant, the multi-target parameter optimization model is re-analyzed until the significance of the variance analysis is achieved;

the coefficient in the blade empirical model is obtained by carrying out multiple linear regression analysis on orthogonal simulation data of the cutting force and the cutting temperature of an orthogonal table, and the cutting force and cutting temperature optimization model is as follows:

F＝10^2.1645n^0.5188f^0.9086α^0.1700R^0.2078 (6)

T＝10^2.2369n^0.9451f^0.5009α^0.1726R^0.6825 (7)

linear weighting is adopted for three optimization models of small cutting force, cutting temperature and large material removal rate, weighting factors are equally divided by 0.33, and the three optimization models are finally converted into a single objective function:

F(x)＝0.33×10^2.1645n^0.5188f^0.9086α^0.1700R^0.2078

+0.33×10^2.2369n^0.9451f^0.5009α^0.1726R^0.6825

-0.33×πdnfa_p (8)

and (3) solving by adopting MATLAB to obtain the main shaft with the optimal rotating speed of 90r/min, the axial feed amount of 0.075mm, the blade back angle of 6 degrees and the cutting edge radius of 0.04 mm.

Secondly, the vibration reduction cutter bar adopts a structure that a circular cavity is added with a vibration reduction element, the cutter bar is converted into a cantilever beam structure, the diameter and the length of the cavity of the vibration reduction cutter bar are determined through calculating the deflection of the vibration reduction cutter bar, and then the verification of the harmonic response vibration amplitude of the cutter bar is carried out through finite element simulation; then, solving a mass block, a spring and damping in the vibration damping element through a dynamic model established by the vibration damping element, and carrying out vibration harmonic response amplitude finite element simulation verification on the vibration damping element after the design of the vibration damping element is finished; the vibration reduction cutter bar is structurally characterized in that a mass element, namely a mass block, capable of suppressing vibration is arranged in a cutter bar cavity, the mass block is supported and fixed by a spring, and the outer side of the mass block is surrounded by damping liquid;

further: carrying out cutter bar harmonic response simulation verification on different diameters and lengths of the cutter bar vibration reduction circular cavity by adopting ANSYS, if the harmonic response amplitude reaches the minimum, considering that the calculated diameter and length of the vibration reduction cavity meet the vibration reduction effect, and if the harmonic response amplitude does not reach the minimum, carrying out deflection calculation again to design the diameter and length of the cavity until the minimum harmonic response amplitude of the cutter bar is met; the dynamic model of the vibration damping element is established for solving the mass of the mass block, the elastic coefficient of the spring and the damping coefficient of the damping liquid so as to select materials, the mass block is connected with the cutter bar through the spring, and the damping liquid is positioned between the mass block and the cavity; after the vibration damping element is designed, carrying out harmonic response simulation comparative analysis on the damping cutter bar and the solid cutter bar through finite element simulation, and if the harmonic response amplitude of the damping cutter bar reaches the minimum value, considering that the vibration damping element meets the vibration damping effect; if the damping cutter bar does not reach the minimum, the damping element is optimized again until the damping effect is met;

further: the vibration damping element comprises a mass block, a spring and damping fluid, wherein the mass block needs to utilize a cutter barThe space is limited, the rigidity of the cutter bar at the vibration reduction cavity is ensured, and the purpose of vibration reduction is realized to the maximum extent, so that the mass of the vibration reduction block is required to be large enough, and the vibration reduction block can be manufactured by using high-density hard alloy YL10.1 to ensure that the vibration reduction block can meet the design requirement; the elastic element adopts butadiene-acrylonitrile rubber as the material of the damping spring; the damping liquid is positioned between the vibration reduction block and the cavity, kinetic energy generated in the turning process can be converted into heat energy, and therefore the purpose of reducing vibration is achieved, the kinematic viscosity of the methyl silicone oil at 25 ℃ is 100-1000000 miles, the damping range is 1.24-12400 N.s/m through calculation, and the damping liquid is completely suitable for vibration reduction cutter bars. The dynamic model of the vibration-damping cutter bar is shown in figure 2, and the vibration-damping cutter bar is simplified into a size of m by the cutter bar per se₁And is used to express the elastic coefficient of the tool bar as k₁Main system and damping system consisting of springs, i.e. mass m₂Spring elastic coefficient k₂And damping coefficient c of damping fluid₂Forming; damping element design, i.e. how to select a damping element parameter m₂、k₂、c₂The method meets the requirement of system vibration reduction, and the method for designing the parameters of the vibration reduction element comprises the following steps: on the premise of ensuring the rigidity of the cutter bar, the mass m of the mass block₂Taking a maximum value; k is a radical of₂Can be represented by formulaObtaining; damping fluid c₂Can be represented by formulaAnd (6) obtaining.

Step three, solving the connecting eccentricity of the screws, wherein only one clamping blade part of the S-type clamping mode is adopted, so that the clamping mode is simple and convenient, and the S-type screw clamping mode is selected; estimating the screw pretightening force, wherein the calculation mode of the screw pretightening force is not more than 80% of the yield limit of a screw material, a reasonable range of the screw pretightening force is given, the screw pretightening force can be obtained in an ANSYS optimization analysis module mode, and the screw pretightening force is set as an optimization variable, and a screw deformation, a screw equivalent stress, a screw shearing stress, a cutter bar deformation and a blade deformation are set as objective functions to obtain the screw pretightening force; the eccentricity can influence the clamping force of the blade and the cutter bar, the screw deformation is increased due to the overlarge eccentricity, the screw is easy to break, the clamping force is insufficient due to the overlarge eccentricity, the blade is easy to loosen, simulation analysis is carried out on different eccentricities through finite element simulation under the action of the pretightening force, and the eccentricity is obtained through simulation by taking the stress deformation of the cutter bar as a consideration index;

further: pretightening force F₀The value of (A) is determined by the conditions of load property, connection rigidity and the like, and generally, the stress generated by the threaded connection under the action of pre-tightening force after being tightened is regulated not to exceed the material yield limit sigma of the threaded connection_s80% of the total weight of the material, based on the yield limit of the selected material, the pretension estimation formula is:

F0≤(0.5～0.6)σ_sA₁ (9)

in the formula A₁Is the area of the dangerous cross-section of the screw,

A₁≈πd²/4 (10)

wherein d is the minor diameter of the screw.

And step four, designing and preparing the vibration reduction tool by combining the step one, the step two and the step three, and verifying the effectiveness of the vibration reduction tool and the matched cutting parameters by analyzing the experimental results of cutting vibration, cutting force and cutting edge abrasion by adopting optimized cutting parameters.

The common cutter and the designed vibration reduction cutter are subjected to experimental comparison, 4 cutters are used, the front angle of 0 degree is adopted, the rear angle of the common cutter adopts 5 degrees, 6 degrees and 7 degrees to verify the effect of the optimized rear angle on vibration suppression, the blade of the vibration reduction cutter adopts the optimized rear angle, and the vibration reduction cutter bar designed and prepared by the method is used. The optimal cutting parameters of the vibration reduction tools are adopted for 4 cutters, namely the rotating speed of a main shaft is 90r/min, the axial feed amount is 0.075mm, and the adopted four cutters are shown in a table 3:

TABLE 3 Experimental tool types and parameters

Referring to fig. 3 to 5, it can be seen from the three-dimensional vibration acceleration effective value, the three-dimensional cutting force and the tool wear extracted in the fine turning of the coarse pitch thread that the vibration reduction tool designed and prepared by the method has the minimum vibration and the minimum tool wear in the cutting process.

The surface roughness of the workpiece finished by the vibration reduction tool is measured, 10 sample blocks are selected, and the obtained thread surface roughness parameter measurement results are shown in table 4.

TABLE 445 # STEEL LARGE-THREAD SURFACE ROUGH VALUE

In Table 4, R_auThe arithmetic mean deviation of the thread surface profile of the screw is that the change range of the machined surface roughness value of the sample block is 1.06-1.53um, the mean value is 1.28um, and the standard deviation is 0.143 um. In the above table, R_auThe maximum value is 1.53um and far less than 2 um; the standard deviation is 0.143um, and the smaller the standard deviation is, the better the surface quality of the workpiece is. Therefore, the surface quality of the workpiece processed by the vibration reduction tool and the matched cutting parameters is higher.

The results show that the vibration reduction tool for turning the large-pitch threads, which is designed and prepared by the method, can effectively reduce the vibration in the process of turning the large-pitch threads by adopting the optimized cutting parameters, and improve the service life of the tool and the surface quality of a workpiece.

The present embodiments are merely exemplary illustrations of the patent and do not limit the scope of the patent, and those skilled in the art can make modifications to the parts thereof without departing from the spirit and scope of the patent.