Instantaneous Uncut Chip Thickness Model in End Milling Based on an Improved Method

2018 ◽  
Vol 764 ◽  
pp. 399-407
Author(s):  
Yue Zhang ◽  
Zhi Qiang Yu ◽  
Tai Yong Wang
Keyword(s):  
End Milling ◽  
Chip Thickness ◽  
Transcendental Equation ◽  
Milling Process ◽  
Force Model ◽  
Uncut Chip Thickness ◽  
Milling Force ◽  
Milling Force Model ◽  
Instantaneous Uncut Chip Thickness ◽  
Taylor’S Series

The instantaneous uncut chip thickness is an important parameter in the study of milling force model. By analyzing the real tooth trajectory in milling process, accurate instantaneous uncut chip thickness can be obtained to solve the complex transcendental equation. Traditional chip thickness models always simplify the tooth trajectory to get approximate solution. A new instantaneous uncut chip thickness model is proposed in this paper. Based on real tooth trajectory of general end milling cutter, a Taylor's series is used to approximate the involved infinitesimal variable in the transcendental equation, which results in an explicit expression for practical application of the uncut chip thickness with higher accuracy compared to the traditional model.

scholarly journals Prediction of Nonlinear Micro-Milling Force with a Novel Minimum Uncut Chip Thickness Model

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1495
Author(s):  
Tongshun Liu ◽  
Kedong Zhang ◽  
Gang Wang ◽  
Chengdong Wang
Keyword(s):  
Cutting Force ◽  
Chip Thickness ◽  
Micro Milling ◽  
Force Model ◽  
Force Coefficient ◽  
Uncut Chip Thickness ◽  
Milling Force ◽  
Minimum Uncut Chip Thickness ◽  
Cutting Force Coefficient ◽  
Milling Force Model

The minimum uncut chip thickness (MUCT), dividing the cutting zone into the shear region and the ploughing region, has a strong nonlinear effect on the cutting force of micro-milling. Determining the MUCT value is fundamental in order to predict the micro-milling force. In this study, based on the assumption that the normal shear force and the normal ploughing force are equivalent at the MUCT point, a novel analytical MUCT model considering the comprehensive effect of shear stress, friction angle, ploughing coefficient and cutting-edge radius is constructed to determine the MUCT. Nonlinear piecewise cutting force coefficient functions with the novel MUCT as the break point are constructed to represent the distribution of the shear/ploughing force under the effect of the minimum uncut chip thickness. By integrating the cutting force coefficient function, the nonlinear micro-milling force is predicted. Theoretical analysis shows that the nonlinear cutting force coefficient function embedded with the novel MUCT is absolutely integrable, making the micro-milling force model more stable and accurate than the conventional models. Moreover, by considering different factors in the MUCT model, the proposed micro-milling force model is more flexible than the traditional models. Micro-milling experiments under different cutting conditions have verified the efficiency and improvement of the proposed micro-milling force model.

Research on Error Compensation of Corner Milling Process Based on Milling Force Prediction

2014 ◽  
Vol 800-801 ◽  
pp. 761-765
Author(s):  
Hui Nan Shi ◽  
Fu Gang Yan ◽  
Yun Peng Ding ◽  
Xian Li Liu ◽  
Rui Zhang
Keyword(s):  
Error Compensation ◽  
Chip Thickness ◽  
Milling Process ◽  
Force Model ◽  
Deformation Model ◽  
Milling Force ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Flexible Deformation ◽  
Milling Force Model

In cavity die corner-machining, tool flexible deformation caused by the milling force resulting in the surface error, a method of off-line error compensation is put forward. Instantaneous chip thickness model and the corner milling force model is established based on differential and the characteristics of the corner. Combining the theory of cantilever beam and the finite element analysis, cutting tool elastic deformation model is established.

Modeling and Simulation of Milling Forces for Ball-End Cutter with Considering Comprehensive Factors

2011 ◽  
Vol 121-126 ◽  
pp. 2098-2104
Author(s):  
Xiu Lin Sui ◽  
Ping Zhang
Keyword(s):  
Chip Thickness ◽  
Milling Process ◽  
Differential Method ◽  
Physical Factors ◽  
Force Model ◽  
Milling Force ◽  
Cutter Deflection ◽  
Set Up ◽  
Milling Forces ◽  
Milling Force Model

In this paper, influence mechanism of variously physical factors for milling force in any feed direction is studied during the milling process. Firstly, the effects of spindle eccentricity, cutter deflection and cutter vibration for the instantaneously undeformed cutting thickness are analyzed, and the mathematical expressions of chip thickness is set up. Then,on this basis of cutting force and chip load, the milling force model of ball-end mill with considering integrated physical factors is established though the differential method, and a simulation system for prediction of milling forces during the milling process is developed. This milling force model is verified through simulation and analysis of milling forces.

Study of the Classification of Cutting Forces and the Build of Accurate Milling Force Model in End Milling

2006 ◽  
Vol 532-533 ◽  
pp. 636-639
Author(s):  
Yong Gang Kang ◽  
Zhong Qi Wang ◽  
Wen Ming Lou ◽  
Cheng Yu Jiang
Keyword(s):  
Cutting Force ◽  
End Milling ◽  
Milling Process ◽  
Force Model ◽  
Milling Force ◽  
Shape Characteristics ◽  
Milling Forces ◽  
Milling Force Model ◽  
The Relationship

A new approach is proposed to model the milling force based on the cutting force shape characteristics in end milling. The relationship between the cutting force shape characteristics and the cutting depths is analyzed and milling forces are classified into 10 types according to the combination of cutting depths. Further, force indices are extracted and then the real cutting depths are detected based on the changes of force curve characteristics via the force indices in end milling process. Then, bring forward a method of modeling cutting force based on the different types, and the use of real cutting depth makes the model to be more accurately. More important, experiments designed on the classification of milling forces strengthen the pertinence, and makes the experiment data more reliable. The approach is validated through experiments on aluminum alloy 7050-T7451.

Modeling and Simulation of Milling Force in Virtual Numerical Control Milling Process

2008 ◽  
Vol 392-394 ◽  
pp. 697-702
Author(s):  
Xiu Lin Sui ◽  
Jia Tai Zhang ◽  
Jiang Hua Ge ◽  
Ya Ping Wang ◽  
H. Yuan
Keyword(s):  
Modeling And Simulation ◽  
Chip Thickness ◽  
Milling Process ◽  
Cutting Edge ◽  
Numerical Control ◽  
Force Model ◽  
End Mill ◽  
Ball End Mill ◽  
Milling Force ◽  
Milling Force Model

A parameter equation based on cutting edge of ball-end mill is set up by analyzing the parameters of ball-end mill influence the milling force in virtual NC milling process. The relationship among elemental cutting force, instantaneous radial chip thickness and cutting edge length is analyzed, and the dynamic milling force of ball-end mill at arbitrary feed direction is established. The milling force parameter model by quadratic regression equation in different cutting conditions is built. Through experiments in NC machining center and using orthogonal combination and principal components analysis, the regression coefficients are calculated. The correctness of milling force model is testified by experiments. All these can provide theoretical basis for physics modeling and simulation of virtual numerical control milling.

Voxel Based Cutting Force Simulation of Ball End Milling Considering Cutting Edge Around Center Web

2018 ◽  
Author(s):  
Isamu Nishida ◽  
Takaya Nakamura ◽  
Ryuta Sato ◽  
Keiichi Shirase
Keyword(s):  
Cutting Force ◽  
End Milling ◽  
Chip Thickness ◽  
Previous Method ◽  
Cutting Edge ◽  
Force Model ◽  
End Mill ◽  
Uncut Chip Thickness ◽  
Ball End Mill ◽  
Tool Rotation

A new method, which accurately predicts cutting force in ball end milling considering cutting edge around center web, has been proposed. The new method accurately calculates the uncut chip thickness, which is required to estimate the cutting force by the instantaneous rigid force model. In the instantaneous rigid force model, the uncut chip thickness is generally calculated on the cutting edge in each minute disk element piled up along the tool axis. However, the orientation of tool cutting edge of ball end mill is different from that of square end mill. Therefore, for the ball end mill, the uncut chip thickness cannot be calculated accurately in the minute disk element, especially around the center web. Then, this study proposes a method to calculate the uncut chip thickness along the vector connecting the center of the ball and the cutting edge. The proposed method can reduce the estimation error of the uncut chip thickness especially around the center web compared with the previous method. Our study also realizes to calculate the uncut chip thickness discretely by using voxel model and detecting the removal voxels in each minute tool rotation angle, in which the relative relationship between a cutting edge and a workpiece, which changes dynamically during tool rotation. A cutting experiment with the ball end mill was conducted in order to validate the proposed method. The results showed that the error between the measured and predicted cutting forces can be reduced by the proposed method compared with the previous method.

Dynamic cutting force prediction for micro end milling considering tool vibrations and run-out

2018 ◽  
Vol 233 (7) ◽  
pp. 2248-2261 ◽  
Author(s):  
Xuewei Zhang ◽  
Tianbiao Yu ◽  
Wanshan Wang
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
End Milling ◽  
Chip Thickness ◽  
Milling Process ◽  
Force Model ◽  
Dynamic Cutting Force ◽  
Micro End Milling ◽  
Tool Vibrations ◽  
End Milling Process

An accurate prediction of cutting forces in the micro end milling, which is affected by many factors, is the basis for increasing the machining productivity and selecting optimal cutting parameters. This paper develops a dynamic cutting force model in the micro end milling taking into account tool vibrations and run-out. The influence of tool run-out is integrated with the trochoidal trajectory of tooth and the size effect of cutting edge radius into the static undeformed chip thickness. Meanwhile, the real-time tool vibrations are obtained from differential motion equations with the measured modal parameters, in which the process damping effect is superposed as feedback on the undeformed chip thickness. The proposed dynamic cutting force model has been experimentally validated in the micro end milling process of the Al6061 workpiece. The tool run-out parameters and cutting forces coefficients can be identified on the basis of the measured cutting forces. Compared with the traditional model without tool vibrations and run-out, the predicted and measured cutting forces in the micro end milling process show closer agreement when considering tool vibrations and run-out.

Force Modeling of Five-Axis Microball-End Milling

2015 ◽  
Vol 3 (3) ◽  
Author(s):  
Chi Xu ◽  
James Zhu ◽  
Shiv G. Kapoor
Keyword(s):  
End Milling ◽  
Elastic Recovery ◽  
Chip Thickness ◽  
Force Model ◽  
End Mill ◽  
Data Simulation ◽  
Force Modeling ◽  
Static Indentation ◽  
Five Axis ◽  
Milling Force Model

This paper presents a five-axis ball-end milling force model that is specifically tailored to microscale machining. A composite cutting force is generated by combining two force contributions from a shearing/ploughing slip-line (SL) field model and a quasi-static indentation (ID) model. To fully capture the features of microscale five-axis machining, a unique chip thickness algorithm based on the velocity kinematics of a ball-end mill is proposed. This formulation captures intricate tool trajectories as well as readily allows the integration of runout and elastic recovery effects. A workpiece updating algorithm has also been developed to identify tool–workpiece engagement. As a dual purpose, historical elastic recovery is stored locally on the meshed workpiece surface in vector form so that the directionality of elastic recovery is preserved for future time increments. The model has been validated through a comparison with five-axis end mill force data. Simulation results show reasonably accurate replication of end milling cutting forces with minimal experimental data fitting.

Sign in / Sign up

Export Citation Format

Share Document