Cutting Force and Tool Deflection Predictions for High Speed Machining of Hard to Cut Material

2010 ◽  
Vol 154-155 ◽  
pp. 1157-1164 ◽  
Author(s):  
Jinn Jong Sheu ◽  
Dong Mei Xu ◽  
Chin Wei Liu
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
High Speed ◽  
Force Model ◽  
Beam Model ◽  
High Speed Machining ◽  
Tool Deflection ◽  
Machining Center ◽  
Helical Angle ◽  
Cutting Experiment

The dimension accuracy and the too life are the major issues of the machining of hard-to-cut materials. To fulfill the requirements of accuracy and tool life needs not only well planning of cutting path but also the proper cutting conditions of cutters. The vibration and deflection of cutters caused by poor selection of cutting conditions can be predicted using models of cutting force and tool deflection. In this paper, a cutting force model considering the effect of tool helical angle and a cantilever beam model of tool deflection were proposed for the high speed machining of hard-to-cut material SKD11. The shearing force, the plowing forces, and the helical angle of cutters are considered in the elemental force model. The material of workpiece, SKD11, studied in this paper is commonly used for the die and mold industries. The cutting constants of the proposed force model are determined via the cutting experiments carried out on a high speed machining center. A dynamometer and a high frequency data acquisition system were used to measure the x-, y-, and z-direction cutting forces. The obtained cutting constants were used to predict the cutting forces and compared with the results obtained from the cutting experiment of verification using cutters with different helical angles. The theoretical and the experimental cutting forces in the x-, y-, and z- direction are in good agreement using flat cutters with 30 and 45 degrees of helical angle. The dimension deviations of the cut surface in the cutting experiment case of tool deflection were measured using a touch probe and an infrared receiver installed on the machining center. The measured average dimension deviation, 0.163mm, is close to the predicted tool deflection, 0.153mm, using the proposed cantilever beam model. The comparisons of the cutting forces and the average of the cut surface dimension deviation are in good agreement and verify the proposed cutting force and the tool deflection models are feasible and useful.

scholarly journals Stability analysis for a single-point cutting tool deflection in turning operation

2019 ◽  
Vol 11 (6) ◽  
pp. 168781401985318
Author(s):  
Amon Gasagara ◽  
Wuyin Jin ◽  
Angelique Uwimbabazi
Keyword(s):  
Cutting Forces ◽  
High Speed ◽  
Cutting Tool ◽  
Single Point ◽  
Three Dimensional ◽  
High Speed Steel ◽  
Cutting Parameters ◽  
Depth Of Cut ◽  
Beam Model ◽  
Tool Deflection

In this article, a new model of regenerative vibrations due to the deflection of the cutting tool in turning is proposed. The previous study reported chatter as a result of cutting a wavy surface of the previous cut. The proposed model takes into account cutting forces as the main factor of tool deflection. A cantilever beam model is used to establish a numerical model of the tool deflection. Three-dimensional finite element method is used to estimate the tool permissible deflection under the action of the cutting load. To analyze the system dynamic behavior, 1-degree-of-freedom model is used. MATLAB is used to compute the system time series from the initial value using fourth-order Runge–Kutta numerical integration. A straight hard turning with minimal fluid application experiment is used to obtain cutting forces under stable and chatter conditions. A single-point cutting tool made from high-speed steel is used for cutting. Experiment results showed that for the cutting parameters above 0.1mm/rev feed and [Formula: see text]mm depth of cut, the system develops fluctuations and higher chatter vibration frequency. Dynamic model vibration results showed that the cutting tool deflection induces chatter vibrations which transit from periodic, quasi-periodic, and chaotic type.

Segmented Cutting Coefficient Based Chatter Modeling for High-Speed Micromilling of Ti6Al4V

2016 ◽  
Author(s):  
Kundan K. Singh ◽  
V. Kartik ◽  
Ramesh Singh
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
High Speed ◽  
Stability Boundary ◽  
Force Model ◽  
Force Prediction ◽  
High Speeds ◽  
Cutting Coefficients ◽  
Stability Lobe ◽  
Chip Load

Miniature components with complex shape can be created by micromilling with high surface accuracy. However, for difficult-to-machine materials, such as Ti-alloys, failure of low flexural stiffness micro-tools is a big limitation. High spindle speeds (20,000 to 100,000 rpm) can be used to reduce the undeformed chip thickness and the cutting forces and hence the catastrophic failure of the tool can be avoided. This reduced uncut chip thicknesses, in some cases lower than the cutting edge radius, can result in intermittent chip formation which can lead to dynamic variation in cutting forces. These dynamic force variations coupled with low flexural rigidity of micro end mill can render the process unstable. Consequently, accurate prediction of forces and stability is essential in high-speed micromilling. Most of the previous studies reported in the literature use constant cutting coefficients in the mechanistic cutting force model which does not yield accurate results. Recent work has shown significant improvement in the prediction of cutting forces with velocity-chip load dependent coefficients but a single function velocity-chip model fails to predict the forces accurately at very high speeds (>80,000 rpm). This inaccurate force prediction affects the predicted stability boundary at those speeds. Hence, this paper presents a segmented approach wherein a function is fit for a given range of speed to determine the chip load dependent cutting coefficients. The segmented velocity-chip load cutting coefficient improves the cutting force prediction at high speeds. R2 value is found to be improved significantly (>90% for tangential cutting coefficient) which yields the better forces prediction and hence more accurate stability boundary. This paper employs two degrees of freedom (2-DOF) model with forcing functions based on segmented velocity-chip load dependent cutting coefficients. Stability lobe diagram based on 2-DOF model has been created for different speed ranges using Nyquist stability criteria. Chatter frequency ranges between 1.003 to 1.15 times the experimentally determined first modal frequency. Chatter onset has been identified via a laser displacement sensor to experimentally validate the predicted stability lobe.

scholarly journals Taguchi parametric study on the radial and tangential cutting forces in Dry High Speed Machining (DHSM)

10.30544/472 ◽  
2020 ◽  
Vol 26 (3) ◽  
pp. 303-316
Author(s):  
M. Hatami ◽  
H. Safari
Keyword(s):  
Titanium Alloy ◽  
Cutting Force ◽  
Feed Rate ◽  
Parametric Study ◽  
Cutting Forces ◽  
High Speed ◽  
Cutting Tools ◽  
High Speed Machining ◽  
Cutting Speeds

In this paper, L8 Taguchi array is applied to find the most important parameters effects on the radial and tangential cutting forces of a Ti–6Al-4V ELI titanium alloy in dry high speed machining (DHSM). The experiments are performed in four cutting speeds of 150, 200, 250, and 300 m/min and two feed rates of 0.03 and 0.06 mm/rev. Also, two cutting tools in types of XOMX090308TR-ME06 of uncoated (H25) and TiAlN+TiN coated (F40M) are used. Results confirm that to minimize the resultant cutting force and radial cutting force, utilizing the lower feed rate and higher cutting speeds were considered as the best levels of factors to reach to its goal.

scholarly journals Analysis of Cutting Forces From Conventional to High-Speed Milling with Straight and Helical-Flute Tools for Flat-End Milling Incorporating the Effect of Tool Runout

2021 ◽  
Author(s):  
Mehmet AYDIN ◽  
Uğur Köklü
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
High Speed ◽  
End Milling ◽  
Spindle Speed ◽  
Force Model ◽  
Workpiece Material ◽  
High Speed Milling ◽  
Tool Runout ◽  
Flat End Milling

Abstract This paper presents a systematic study to analyze the dependence of cutting forces on tool geometry, workpiece material and cutting parameters such as spindle speed, tool engagement and cutting direction in flat-end milling with tool runout. The cutting forces are determined according to a mechanistic force model considering the trochoidal flute path to calculate the undeformed chip thickness, and average cutting force and linear regression model are applied for identifying the coefficients of the force model. A series of milling processes are conducted on AZ31 Magnesium (Mg) alloy and titanium alloy (Ti6Al4V) to analyze the instantaneous cutting force curves, amplitudes of cutting forces and peak forces over a wide range of spindle speeds from conventional to high-speed milling. It is demonstrated that the values of the cutting force coefficients are higher at conventional spindle speed and decrease with an increase in spindle speed, especially when machining Ti6Al4V alloy. For the edge force coefficients, it is observed a slight variation when using cutting tools with different helix angles. Besides, the cutting force amplitudes strongly depend upon the workpiece material. The helix angle has a significant influence on the transverse force amplitude at conventional speed. The forces obtained mechanistically are also substantiated by comparison with measurements.

Research on Multi-Axis High Speed Machining Milling Force of Aeroengine Impeller

2010 ◽  
Vol 455 ◽  
pp. 87-91
Author(s):  
Y.Y. Guo ◽  
Can Zhao ◽  
Wei Gang Du
Keyword(s):  
Cutting Force ◽  
High Speed ◽  
End Milling ◽  
Model Simulation ◽  
Differential Method ◽  
Force Model ◽  
High Speed Machining ◽  
Cutting Force Model ◽  
Ball End Milling ◽  
The Relationship

On the basis of the ball-end milling feature during high-speed machining impeller, the relationship between cutting force and chips is analyzed in this paper. The model of ball-end milling cutter cutting force is founded through differential method. And the coefficients solution of cutting force model is expounded. Besides, the coefficients solution and the cutting force model simulation are implemented by the software Matlab.

Modeling of Dynamic Instability Via Segmented Cutting Coefficients and Chatter Onset Detection in High-Speed Micromilling of Ti6Al4V

2016 ◽  
Vol 139 (5) ◽  
Author(s):  
Kundan K. Singh ◽  
V. Kartik ◽  
Ramesh Singh
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
High Speed ◽  
Stability Boundary ◽  
Force Model ◽  
Dynamic Force ◽  
Force Prediction ◽  
High Speeds ◽  
Cutting Coefficients ◽  
Chip Load

Miniature components with complex shape can be created by micromilling with excellent form and finish. However, for difficult-to-machine materials, such as Ti-alloys, failure of low-flexural stiffness microtools is a big limitation. High spindle speeds (20,000–100,000 rpm) can be used to reduce the undeformed chip thickness and the cutting forces to reduce the catastrophic failure of the tool. This reduced uncut chip thicknesses, in some cases lower than the cutting edge radius, can result in intermittent chip formation which can lead to dynamic variation in cutting forces. In addition, the run-out and the misalignment effects are amplified at higher rotational speeds which can induce dynamic force variation. These dynamic force variations coupled with low-flexural rigidity of micro end mill can render the process unstable. Consequently, accurate prediction of forces and stability is essential in high-speed micromilling. Most of the previous studies reported in the literature use constant cutting coefficients in the mechanistic cutting force model which does not yield accurate results. Recent work has shown significant improvement in the prediction of cutting forces with velocity–chip load dependent coefficients but a single-function velocity–chip model fails to predict the forces accurately at very high speeds (>80,000 rpm). This inaccurate force prediction affects the predicted stability boundary at those speeds. Hence, this paper presents a segmented approach, wherein a function is fit for a given range of speeds to determine the chip load dependent cutting coefficients. The segmented velocity–chip load dependent cutting coefficient improves the cutting force prediction at high speeds, which yields much accurate stability boundary. This paper employs two degrees-of-freedom (2DOF) model with forcing functions based on segmented velocity–chip load dependent cutting coefficients. Stability lobe diagram based on 2DOF model has been created for different speed ranges using Nyquist stability criterion. Chatter onset has been identified experimentally via accelerometer data and the power spectral density (PSD) analysis of the machined surface topography. Critical spatial chatter frequencies and magnitudes of PSD corresponding to onset of instability have also been determined for different conditions.

The Research of High Speed Machining Technology for Sub-Regional Complex Surfaces Based on Feature

2011 ◽  
Vol 58-60 ◽  
pp. 48-53 ◽  
Author(s):  
Chun Jiang Zhou ◽  
Hong Chun Chen
Keyword(s):  
Cutting Force ◽  
High Speed ◽  
Complex Surface ◽  
Surface Shape ◽  
Normal Vector ◽  
Force Model ◽  
High Speed Machining ◽  
Oblique Angle ◽  
Tool Axis ◽  
Regional Process

The high speed machining technology of complex surface has been a focus of the study. Based on the analysis of cutting force model for ball-end cutters and cutting force tests of 3-axis machining, the paper brings forward the reasonable oblique angle of tool axis for complex surface with different curvature. According to the different feature of surface shape, the surface is classified in terms of oblique angle formed by tool axis and normal vector of surface. Meanwhile, the processing methods are proposed to adapt to classification of surface. Adopting 3+2 axis method in 5 axis machine to processing complex surface with different features by sub-regional process will effectively improve the surface quality and extend tool life. The paper finally put forward the high speed supplementary processing technology to process the boundary and transition area of surface.

Cutting Temperature and Cutting Forces Investigation Based on the Taguchi Design Method when High-Speed Milling of Titanium Matrix Composites with PCD Tool

2016 ◽  
Vol 836-837 ◽  
pp. 168-174 ◽  
Author(s):  
Ying Fei Ge ◽  
Hai Xiang Huan ◽  
Jiu Hua Xu
Keyword(s):  
Cutting Force ◽  
Feed Rate ◽  
Cutting Forces ◽  
High Speed ◽  
Volume Fraction ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
High Speed Milling ◽  
Radial Depth

High-speed milling tests were performed on vol. (5%-8%) TiCp/TC4 composite in the speed range of 50-250 m/min using PCD tools to nvestigate the cutting temperature and the cutting forces. The results showed that radial depth of cut and cutting speed were the two significant influences that affected the cutting forces based on the Taguchi prediction. Increasing radial depth of cut and feed rate will increase the cutting force while increasing cutting speed will decrease the cutting force. Cutting force increased less than 5% when the reinforcement volume fraction in the composites increased from 0% to 8%. Radial depth of cut was the only significant influence factor on the cutting temperature. Cutting temperature increased with the increasing radial depth of cut, feed rate or cutting speed. The cutting temperature for the titanium composites was 40-90 °C higher than that for the TC4 matrix. However, the cutting temperature decreased by 4% when the reinforcement's volume fraction increased from 5% to 8%.

Analytical cutting force modelling of micro-slot grinding considering tool-workpiece interactions on both primary and secondary tool surfaces

2021 ◽  
pp. 1-43
Author(s):  
Ashwani Pratap ◽  
Karali Patra
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
Orthogonal Cutting ◽  
Surface Interactions ◽  
Surface Interaction ◽  
Edge Density ◽  
Force Model ◽  
Height Distribution ◽  
Force Modeling ◽  
Tool Surface

Abstract This work presents an analytical cutting force modeling for micro-slot grinding. Contribution of the work lies in the consideration of both primary and secondary tool surface interactions with the work surface as compared to the previous works where only primary tool surface interaction was considered during cutting force modeling. Tool secondary surface interaction with workpiece is divided into two parts: cutting/ ploughing by abrasive grits present in exterior margin of the secondary tool surface and sliding/adhesion by abrasive grits in the inner margins of the secondary tool surface. Orthogonal cutting force model and indentation based fracture model is considered for cutting by both the abrasives of primary tool surface and the abrasives of exterior margin on the secondary surface. Asperity level sliding and adhesion model is adopted to solve the interaction between the workpiece and the interior margin abrasives of secondary tool surface. Experimental measurement of polycrystalline diamond tool surface topography is carried out and surface data is processed with image processing tools to determine the tool surface statistics viz., cutting edge density, grit height distribution and abrasive grit geometrical measures. Micro-slot grinding experiments are carried out on BK7 glass at varying feed rate and axial depths of cut to validate the simulated cutting forces. Simulated cutting forces considering both primary and secondary tool surface interactions are found to be much closer to the experimental cutting forces as compared to the simulated cutting forces considering only primary tool surface interaction.

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