scholarly journals An Improved Cutting Force Model for Ultrasonically Assisted Grinding of Hard and Brittle Materials

2021 ◽  
Vol 11 (9) ◽  
pp. 3888
Author(s):  
Renke Kang ◽  
Jinting Liu ◽  
Zhigang Dong ◽  
Feifei Zheng ◽  
Yan Bao ◽  
...  

Cutting force is one of the most important factors in the ultrasonically assisted grinding (UAG) of hard and brittle materials. Many theoretical and experimental studies show that UAG can effectively reduce cutting forces. The existing models for UAG mostly assume an ideal grinding wheel with abrasives in both the end and lateral faces to accomplish material removal, whereas the important role of the transition fillet surface is ignored. In this study, a theoretical cutting force model is presented to predict cutting forces with the consideration of the diamond abrasives in the end face, the lateral face, and the transition fillet surface of the grinding tool. This study analyzed and calculated the vibration amplitudes and the cutting forces in both the normal and tangential directions. It discusses the influences of the input parameters (rotation speed, feed rate, amplitude, depth and radius of transition fillet) on cutting forces. The study demonstrates that the fillet radius is an important factor affecting the grinding force. With an increase in fillet radius from 0.2 to 1.2 mm, the grinding force increases by 139.6% in the axial direction and decreases by 70% in the feed direction. The error of the proposed cutting force model is 10.3%, and the experimental results verify the correctness of the force model.

2017 ◽  
Vol 11 (6) ◽  
pp. 958-963
Author(s):  
Koji Teramoto ◽  
◽  
Takahiro Kunishima ◽  
Hiroki Matsumoto

Elastomer end-milling is attracting attention for its role in the small-lot production of elastomeric parts. In order to apply end-milling to the production of elastomeric parts, it is important that the workpiece be held stably to avoid deformation. To evaluate the stability of workholding, it is necessary to predict cutting forces in elastomer end-milling. Cutting force prediction for metal workpiece end-milling has been investigated for many years, and many process models for end-milling have been proposed. However, the applicability of these models to elastomer end-milling has not been discussed. In this paper, the characteristics of the cutting force in elastomer end-milling are evaluated experimentally. A standard cutting force model and its parameter identification method are introduced. By using this cutting force model, measured cutting forces are compared against the calculated results. The comparison makes it clear that the standard cutting force model for metal end-milling can be applied to down milling for a rough evaluation.


Author(s):  
Zhichao Niu ◽  
Kai Cheng

The effects of cutting dynamics and the particles' size and density cannot be ignored in micro milling of metal matrix composites. This article presents the improved dynamic cutting force modelling for micro milling of metal matrix composites based on the previous analytical model. This comprehensive improved cutting force model, taking the influence of the tool run-out, actual chip thickness and resultant tool tip trajectory into account, is evaluated and validated through well-designed machining trials. A series of side milling experiments using straight flutes polycrystalline diamond end mills are carried out on the metal matrix composite workpiece under various cutting conditions. Subsequently, the measured cutting forces are compensated by a Kalman filter to achieve the accurate cutting forces. These are further compared with the predicted cutting forces to validate the proposed dynamic cutting force model. The experimental results indicate that the predicted and measured cutting forces in micro milling of metal matrix composites are in good agreement.


Author(s):  
Han Ul Lee ◽  
Dong-Woo Cho

In this paper, a milling process simulation system was constructed and ME Z-map (Moving Edge node Z-map) model was developed to elevate the performance of this system. The milling process simulation system computes the cutting configuration and then the cutting forces are predicted using these calculated configurations. In this system, an improved cutting force model which is independent of cutting conditions is used to more precisely predict the cutting forces. In the process, the ME Z-map model was used for more accurate computing of cutting configuration. Due to the edge node, ME Z-map model produces more accurate cutting configuration than the conventional Z-map models even with five to ten times larger grid size, which reduces the computing time dramatically. The superiority of the ME Z-map model was confirmed through comparison with the conventional Z-map.


2011 ◽  
Vol 188 ◽  
pp. 404-409 ◽  
Author(s):  
Xue Yan ◽  
Hua Tao ◽  
D.H. Zhang ◽  
B.H. Wu

A developed method to predict the cutting forces in end milling of generalized corners is proposed in this paper. The cornering milling process is divided into a series of cutting segments with different cutting states. The mathematical model of the geometric relationship between cutter and the corner profile is established for each segment. Cutting forces is predicted by introducing the classical cutting force model. The computational results of cutting forces are in good agreement with experimental data.


1999 ◽  
Author(s):  
Hsi-Yung (Steve) Feng ◽  
Ning Su

Abstract The prediction and optimization of cutting forces in the finishing machining of 3D plane surfaces using ball-end milling are presented in this paper. The cutting force model is developed based on the mechanistic modeling approach. This improved model is able to accurately predict the cutting forces for non-horizontal and cross-feed cutter movements typical in 3D finishing ball-end milling. Optimization of the cutting forces is used to determine both the tool path and the maximum feed rate in 3D plane surface finishing machining. The objective is to achieve highest machining efficiency and to ensure product quality. Experimental results have shown that the cutting force model gives excellent predictions of cutting forces in 3D finishing ball-end milling. The feasibility of the integrated process planning method has been demonstrated through the establishment of optimized process plans for the finishing machining of 3D plane surfaces.


1998 ◽  
Vol 120 (1) ◽  
pp. 49-56 ◽  
Author(s):  
B. K. Ganapathy ◽  
I. S. Jawahir

The present tendency towards increased automation of metal cutting operations has resulted in a need to develop a model for the chip breaking process. Conventional cutting force models do not have any provision for the study of chip breaking since they assume a continuous mode of chip formation, where the contact action of the free-end of the chip is ignored in all analyses. The new cutting force model proposed in this work incorporates the contact force developed due to the free-end of the chip touching the workpiece, and is applicable to the study of two-dimensional chip breaking in orthogonal machining. Orthogonal cutting tests were performed to obtain two-dimensional chip breaking. The experimentally measured cutting forces show a good correlation with the estimated cutting forces using the model. Results show that the forces acting on the chip vary within a chip breaking cycle and help identify the chip breaking event.


Author(s):  
Ramesh Singh ◽  
Shreyes N. Melkote

Laser assisted mechanical micromachining is a process that utilizes highly localized thermal softening of the material by continuous wave laser irradiation applied simultaneously and directly in front of a miniature cutting tool in order to produce micron scale three-dimensional features in difficult-to-machine materials. The hybrid process is characterized by lower cutting forces and deflections, fewer tool failures, and potentially higher material removal rates. The desktop-sized machine used to implement this process has a finite stiffness and deflects under the influence of the cutting forces. The deflections can be of the same order of magnitude as the depth of cut in some cases, thereby having a negative effect on the dimensional accuracy of the micromachined feature. As a result, selection of the laser and cutting parameters that yield the desired reduction in cutting forces and deflection, and consequently an improvement in dimensional accuracy, requires a reliable cutting force model. This paper describes a cutting force model for the laser-assisted microgrooving process. The model accounts for the effect of elastic deflection of the machine X-Y stages on the forces and accuracy of the micromachined feature. The model combines an existing slip-line field based force model with a finite element based thermal model of laser heating and a constitutive material flow stress model to account for thermal softening. Experiments are carried out on H-13 steel (42 HRC (hardness measured on the Rockwell ‘C’ scale)) to validate the force model. The effects of process parameters, such as laser power and cutting speed, on the forces are also analyzed. The model captures the effect of thermal softening and indicates a 66% reduction in the shear flow stress at 35 W laser power. The cutting force and depth of cut prediction errors are less than 20% and 10%, respectively, for most of the cases examined.


2010 ◽  
Vol 97-101 ◽  
pp. 1961-1964 ◽  
Author(s):  
Wei Guo Wu ◽  
Gui Cheng Wang ◽  
Chun Gen Shen

In this work, the prediction and analysis of cutting forces in precision turning operations is presented. The model of cutting forces is based on the oblique cutting force model which was rebuilt by two coordinate conversions from the orthogonal cutting model. Then the cutting field in precision turning was divided into two fields which are characterized as curve change and linear change on cutter edge and they were modeled respectively. Cutting field of cutter nose was modeled by differential method and its cutting force distribution is predicted by the proposed method. The predicted results for the cutting forces are in agreement with the experimental results under a variety of operation variables, including changes in the depths of cut and in the feedrate.


Author(s):  
Bryan Javorek ◽  
Barry K. Fussell ◽  
Robert B. Jerard

Changes in cutting forces during a milling operation can be associated with tool wear and breakage. Accurate monitoring of these cutting forces is an important step towards the automation of the machining process. However, direct force sensors, such as dynamometers, are not practical for industry application due to high costs, unwanted compliance, and workspace limitations. This paper describes a method in which power sensors on the feed and spindle motors are used to generate coefficients for a cutting force model. The resulting model accurately predicts the X and Y cutting forces observed in several simple end-milling tests, and should be capable of estimating both the peak and average force for a given cut geometry. In this work, a dynamometer is used to calibrate the feed drive power sensor and to measure experimental cutting forces for verification of the cutting force model. Measurement of the average x-axis cutting forces is currently presented as an off-line procedure performed on a sacrificial block of material. The potential development of a continuous, real-time force monitoring system is discussed.


2010 ◽  
Vol 42 ◽  
pp. 242-245
Author(s):  
Yong Jie Ma ◽  
Yi Du Zhang ◽  
Xiao Ci Zhao

In the present study, aluminum alloy 2014 was selected as workpiece material, cutting forces were measured under turning conditions. Cutting parameters, the depth of cut, feed rate, the cutting speed, were considered to arrange the test research. Mathematical model of turning force was solved through response surface methodology (RSM). The fitting of response surface model for the data was studied by analysis of variance (ANOVA). The quadratic model of RSM associated with response optimization technique and composite desirability was used to find optimum values of machining parameters with respect to cutting force values. The turning force coefficients in the model were calibrated with the test results, and the suggested models of cutting forces adequately map within the limits of the cutting parameters considered. Experimental results suggested that the most cutting force among three cutting forces was main cutting force. Main influencing factor on cutting forces was obtained through cutting force models and correlation analysis. Cutting force has a significant influence on the part quality. Based on the cutting force model, a few case studies could be presented to investigate the precision machining of aluminum alloy 2014 thin walled parts.


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