自由切削阶梯端铣刀铣削力试验研究

在传统阶梯端铣刀大平面铣削加工中,能采用较大的切削深度、进给速度和较高的铣削速度以提高铣削效率,但切削深度不能大于刀片边长的2/3,刀具耐用度和生产率较低。本文介绍了一种自由切削阶梯端铣刀的基本理论,每齿进给量和切削深度较大,能有效提高加工效率。通过铣削力试验,证明该自由切削阶梯端铣刀的铣削力比传统端铣刀低30%以上,刀具耐用度提高。     

Cutting Force Model for a Small-diameter Helical Milling Cutter

In the milling process, the major flank wear land area (two-dimensional measurement for the wear) of a small-diameter milling cutter, as wear standard, can reflect actual changes of the wear land of the cutter. By analyzing the wearing characteristics of the cutter, a cutting force model based on the major flank wear land area is established. Characteristic parameters such as pressure parameter and friction parameter are calculated by substituting tested data into their corresponding equations. The cutting force model for the helical milling cutter is validated by experiments. The computational and experimental results show that the cutting force model is almost consistent with the actual cutting conditions. Thus, the cutting force model established in the research can provide a theoretical foundation for monitoring the condition of a milling process that uses a small-diameter helical milling cutter.     

球头铣刀切削力模型的研究进展

综合评述了国内外对球头铣刀切削力模型的研究成果及发展动态,重点介绍了球头铣刀铣削力的经验系数建模、理论建模和自动化加工铣削力建模方法。     

球头铣刀切削力计算机预报模型的数值仿真

借助建立的铣刀切削力、扭矩和切削功率的计算机预报模型 ,对平前刀面球头铣刀的切削性能进行了数值仿真研究 ;通过分析各种切削参数对切削性能的影响规律 ,获得了不同切削条件下球头铣刀切削力和扭矩的特征和变化趋势     

Investigation of Cutting Force by End Milling Operation

In this work, the cutting forces by end milling operation are analyzed. Therefore, the main parameters of cutting force as cutting speed, feed rate and depth of cut also are investigated in our case. The cutting force is modelled and analyzed into mathematical Wolfram simulations in order to compare the results and in the same time achieve the best solutions. Theoretical results are carried out by using the regression method that required fulfilling the critter by Fisher. The number of experiment, measurements and results of cutting force are presented in 2D as well as 3D. In order to verify the accuracy of the 2D diagram, the results for our case is used both two way such as experimental and theoretical method as well as results are compared. In other hands, these results indicate directly that the optimized parameters are capable of machining the workpiece. The obtained measurement results are compared with theoretical methods in Wolfram software.     

Analysis of Cutting Force by End Milling Using Artificial ntelligence

The cutting forces during end milling process by using Genetic Algorithm are investigated in this paper. However, automated CNC （computer numerical control） programming by milling machine is intended to use for special required conditions of programming of tool path length, and analysis of cutting force and optimization of main parameters are presented. Some effective simplification of automated programming is done for cutting force. The cutting force is modelled and analyzed into mathematical simulations in order to optimize the main cutting parameters, also in this case tool path length, it is get as free trajectory. Optimization is carried out by using the Matlab/Genetic Algorithm method that excessively reduce the time and to optimize the main cutting parameters of machining. The number of experiments, measurements and results of cutting force （F~）, are presented in 3D as well as in tables. In order to verify the accuracy of the 3 D simulation with optimization method, the results are compared in experimental and theoretical way. In other word, these results indicate directly that the optimized parameters are capable of machining the workpiece. Achieved results that are presented in this paper may in general help the new researcher as well as manufacturing industries of metal cutting.     

立铣刀用弹簧夹头的夹持稳定性分析

对直柄立铣刀切削时的受力、变形及影响夹持稳定性的因素进行了分析，阐述了立铣刀夹持不稳对铣削质量的影响，提出了保证立铣刀夹持稳定性的措施。     

变螺旋铣刀铣削力系数识别试验研究

基于变螺旋铣削模型,采用快速标定法,建立了变螺旋铣刀铣削力系数模型。对变螺旋铣刀铣削力系数识别进行了实验研究,在所给定的条件下获得了变螺旋铣刀铣削力系数。试验结果为后续铣削力实验的设计和数据处理提供了理论依据。     

PCBN刀具端面铣削淬火钢的铣削力研究

通过试验分别研究了铣削用量、刀具几何参数、工件材料硬度、刀具磨损情况和PCBN材料的晶粒粒度对铣削力的影响，得出了铣削力的经验公式，并提出了降低铣削力的具体途径。     

微细立铣削的切削力试验研究

基于直槽的微细立铣削试验,分析了微细铣削力的基本特征,研究了铣削参数对静态和动态铣削力的影响规律。结果表明:与常规尺度立铣削不同,微细立铣削的动态铣削力均大于静态铣削力;直槽微铣削时,进给方向上的静态铣削力和动态铣削力均大于槽宽方向;三个铣削参数对铣削力有着不同的影响规律。     

S形刃球头立铣刀的数学模型

建立了S形刃球头立铣刀内前刀面、外前刀面及螺旋后刀面、平面后刀面的数学模型。该模型的建立为球头立铣刀刃磨参数选择及刃磨装置设计具有重要的作用。     

Improved Dynamic Cutting Force Model in Peripheral Milling. Part I: Theoretical Model and Simulation

The accurate prediction of cutting forces is important in controlling the tool deflection and the machining accuracy. In this paper, the authors present an improved theoretical dynamic cutting-force model for peripheral milling with helical end-mills. The theoretical model is based on the oblique cutting principle and includes the size effect of undeformed chip thickness and the influence of the effective rake angle. A set of closed-form analytical expressions is presented. Using the cutting forces measured by Yucesan [1] in tests on a titanium alloy, the cutting-force coefficients are estimated and the cutting- force model verified by simulation. The simulation results indicate that the improved dynamic cutting-force model does predict the cutting forces in peripheral milling accurately. Simulation results for a number of particular examples are presented. ID="A1" Correspondence and offprint requests to: Prof K. Cheng, School of Engineering, Leeds Metropolitan University, City Campus, Calverley Street, Leeds LS1 3HE, UK. E-mail: k.cheng@lmu.ac.uk     

整体式立铣刀三维建模及切削力预测研究

针对立铣刀三维建模困难及铣削时切削力难以预测等问题,根据微分几何原理建立立铣刀数学模型。基于数学模型将铣刀切削刃离散成斜角切削单元,根据剪切区应力、应变和温度控制方程,由材料本构方程计算流动应力,通过坐标变换关系建立铣削力预测模型。得到的铣削力与已有铣削试验数据一致,验证了铣削力模型的有效性。     

平头立铣刀铣削力模型中积分限的确定方法

在铣削力预报的研究中 ,通常采用的方法是将铣刀沿其轴线方向逐层划分为很薄的微单元 ,对每一个微单元可认为是一个单刃刀具的斜角切削过程 ,通过建立微单元上的切削力模型并沿轴线方向积分来求得总的切削力 ,轴向积分限通常是通过角度换算获取 ,比较繁琐。本文对刀具的几何特征进行了描述 ,建立了求取平头立铣刀铣削力模型角度积分限的通用方法 ,该方法通过分析刀具几何特征和加工类型 ,直接获取角度积分限 ,避免了繁琐的轴向积分限的计算 ,并通过算例验证了该方法的有效性。     

端铣刀铣削加工铝合金铣削力试验及切屑分析

采用正交试验设计方法对铝合金进行铣削试验,测得了不同切削用量情况下硬质合金铣刀的铣削力。运用方差分析法确定了主轴转速、轴向切深、径向切深、进给速度等切削参数对切削力的影响程度,并对切屑进行了金相分析。这为设计刀具和选择切削用量提供了借鉴。     

球头铣刀骨铣削力有限元建模与试验验证

在骨科手术中,铣削力对骨裂纹和加工表面质量影响较大。由于临床球形骨铣刀结构复杂,目前尚无有效的理论模型预测切削力。通过引入三维有限元模型模拟球形铣刀加工骨材料过程,评估不同加工参数下的铣削力值。搭建骨铣削试验平台模拟临床操作中的铣削过程,并利用采集到的加工信号分析铣削力。通过试验结果与仿真结果的对比,验证了有限元仿真模型的合理性。该骨铣削有限元模型能够满足不同加工参数下铣削力预测精度的要求,方便指导医生根据不同要求选择合适的加工参数。     

基于Z-MAP方法的球头铣刀铣削力的建模

瞬时刚性切削力的建模是铣削加工物理仿真的基础,然而,球头铣刀的刀齿形状复杂,加工过程中姿态多变,瞬时刚性铣削力的建模难度较大。在考虑刀具姿态调整的情况下,通过齐次坐标变换建立了刀齿的运动轨迹,提出了一种识别刀具和工件瞬时接触区的改进Z-MAP算法,通过计算当前刀齿的参考线与工件的边界面或刀齿扫掠面的交点求出瞬时未变形切屑厚度,并采用非线性回归的方法辨识了切削力系数,在此基础上使用微元积分法建立了瞬时切削力的计算模型。为了验证仿真模型的可靠性,分别进行了垂直加工和倾斜加工试验,试验和仿真结果具有较高的一致性,表明该建模仿真方法是有效的,可以为实际加工中参数的选择和优化提供理论依据。     

球头铣刀铣削模式与切削性能的计算机辅助预报

讨论并建立了球头铣刀切削几何参数数学模型和铣削过程中切削力、扭矩及切削功率计算机预报数学模型。分析了球头铣刀的铣削模式和铣削中刀具一工件的干涉过程。以车削斜角切削数据库为基础，实现了平面前刀面球头铣刀铣削性能的计算机预报，并通过数值模拟和切削实验对所建立的数学模型进行了验证。     

An Improved Method for the Determination of 3D Cutting Force Coefficients and Runout Parameters in End Milling

A simple improved method is suggested for determining constant cutting force coefficients, irrespective of the cutting condition and cutter rotation angle. This can be achieved through the combination of experimentally deternimed cutting forces with those from simulation, performed by a mechanistic cutting force model and a geometric uncut chip thickness model. Additionally, this study presents an approach that estimates runout-related parameters, and the runout offset and its location angle, using only one measurement of cutting force. This method of estimating 3D end milling force coefficients was experimentally verified for a wide range of cutting conditions, and gave significantly better predictions of cutting forces than any other methods. The estimated value of the runout offset also agreed well with the measured value.     

Dynamic Force Modelling for a Ball-End Milling Cutter Based on the Merchant Oblique Cutting Theory

A new dynamic force model for a ball-end milling cutter is presented in this paper. Based on the principle of the power remaining constant in cuts, the Merchant oblique cutting theory has been successfully used for the differential cutting edge segment of a ball-end milling cutter. A concise method for characterising the relationship of the complex geometry of a ball-end milling cutter and the milling process variables is determined, so that the force coefficients can be decomposed. The geometric property of a ball-end milling cutter and the dynamics of the milling process are integrated into the general model to eliminate the need for the experimental calibration of each cutter geometry and milling process variable. The milling experiments prove that this model can predict accurately the cutting forces in three Cartesian directions.