A Time Domain Dynamic Simulation Model for Stability Prediction of Infeed Centerless Grinding Processes

2006 ◽  
Vol 129 (3) ◽  
pp. 539-550 ◽  
Author(s):  
Hongqi Li ◽  
Yung C. Shin
Keyword(s):  
Chip Thickness ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Deformation Model ◽  
Two Dimensional ◽  
New Model ◽  
Grinding Processes ◽  
Centerless Grinding ◽  
Surface Profiles

This paper presents a comprehensive dynamic model that simulates infeed centerless grinding processes and predicts their instability-related characteristics. The new model has the unique ability of accurately predicting the coupled chatter and lobing process of a multi-degree of freedom and two-dimensional centerless grinding system by considering its critical issues. First, the model considers the complete two-dimensional kinematics, dynamics, surface profiles, and the geometrical interactions of the workpiece with the grinding wheel, regulating wheel, and supporting blade. Second, a two-dimensional distributed grinding force model along the contact length is adopted and modified for centerless grinding processes as a function of normalized uncut chip thickness. The forces of the work holding system are determined by balancing the grinding force and accordingly the work holding instability can be identified as well. Third, a two-dimensional contact deformation model under the condition of general surface profiles or pressure distributions is developed for the contacts of the workpiece with the grinding wheel, regulating wheel, and supporting blade. The new model is validated by comparing the predicted chatter and lobing occurrences with experimental results.

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 ◽  
...  
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
Experimental Studies ◽  
Brittle Materials ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Cutting Force Model ◽  
Fillet Radius ◽  
Hard And Brittle Materials

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.

Mathematical Model of the Grinding Force With Account for Blunting of Abrasive Grains of the Grinding Wheel

2017 ◽  
Vol 139 (12) ◽  
Author(s):  
Dmitrii V. Ardashev ◽  
Aleksandr A. Dyakonov
Keyword(s):  
Forecast Model ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Cyclic Loads ◽  
Workpiece Material ◽  
Stochastic Nature ◽  
Abrasive Grains ◽  
Working Surface ◽  
Abrasive Grain

The paper offers a simulation model of the grinding force with account for the current condition of the grinding wheel's working surface—the value of the abrasive grain blunting area. The model of blunting area takes into account various wear mechanisms for abrasive grains: the mechanical wear is realized on the provisions of the kinetic theory of the strength of a solid subjected to cyclic loads, and the physicochemical wear is based on the intensity of interaction between the abrasive and the treated material at grinding temperatures. The offered model of the grinding force takes into account the unsteady stochastic nature of the interaction between abrasive grains of the grinding wheel and the working surface and the intensity of workpiece material deformation resistance. The model is multifactorial and complex and can be realized by supercomputer modeling. The numerical implementation of the model was performed with application of supercomputer devices engaging parallel calculations. The performed experiments on measurement of the grinding force during circular grinding have shown a 10% convergence with the calculated values. The developed grinding force model can be used as a forecast model to determine the operational functionality of grinding wheel when used in varying technological conditions.

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.

A New Approach to Development of a Grinding Force Model

1987 ◽  
Vol 109 (4) ◽  
pp. 306-313 ◽  
Author(s):  
M. Younis ◽  
M. M. Sadek ◽  
T. El-Wardani
Keyword(s):  
Fiber Optics ◽  
Tangential Force ◽  
Chip Thickness ◽  
Grinding Wheel ◽  
Force Model ◽  
Stress Coefficient ◽  
Tangential Forces ◽  
Force Components ◽  
A New Technique ◽  
Loaded Area

A theoretical model has been developed for representing the grinding forces. This is based on the fact that the chip formation during grinding consists of three states: ploughing, cutting, and rubbing. Expressions for the total normal and tangential force components during these three stages were established. These components were expressed in terms of the chip thickness coefficient, the friction coefficient between the grit tip area and the workpiece, the stress coefficient arising during ploughing and, finally, the loading coefficient. The latter is expressed as an exponential in time. All these coefficients were determined experimentally by performing normal grinding tests at specified configurations. During these tests the forces were measured simultaneously with the loaded area on the grinding wheel during the process of grinding. The loaded area on the wheel surface was measured by a new technique using fiber-optics. This is based on the measurement of the reflectivity of the loaded particles. This system was calibrated by high magnification photographs taken of the surface texture. The predicted normal and tangential forces during the grinding process were compared with those experimentally obtained during the grinding tests mentioned earlier, showing reasonable agreement, both quantitatively and qualitatively.

A Theoretical Model of Grinding Force and its Simulation

2013 ◽  
Vol 690-693 ◽  
pp. 2395-2402 ◽  
Author(s):  
De Lin Qin ◽  
Feng Wang ◽  
Fang Jian Xi ◽  
Zhi Feng Liu
Keyword(s):  
High Speed ◽  
Mutual Authentication ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Force Coefficient ◽  
Element Analysis ◽  
Cylindrical Grinding ◽  
Grinding Force Model ◽  
Force Calculation

Aiming at the axle material 30CrMoA high speed cylindrical grinding force calculation problems, a consideration of plowing force grinding force model is established based on the Werner’s theory model of grinding force, and the friction force and plowing force coefficient is defined as variable parameters. On the basis of the finite element analysis software DEFORM-3D, a high speed cylindrical grinding simulation model method is presented.Through the theoretical value and simulation value contrast, a mutual authentication of grinding force model is proposed. According to the simulation analysis results of grinding force and grinding wheel speed, grinding depth and the relationship between the workpiece speed, theoretical and technical guidance for the grinding force calculation and the selection of grinding process parameters are provided.

The X-C Linkage Grinding Force Model in Cam Grinding

2016 ◽  
Vol 693 ◽  
pp. 1187-1194
Author(s):  
Xiu Mei Chen ◽  
Qiu Shi Han ◽  
Bao Ying Peng ◽  
Qi Guang Li
Keyword(s):  
Theoretical Basis ◽  
Mechanical Analysis ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Grinding Force Model ◽  
Cam Profile ◽  
Contour Accuracy ◽  
Servo Tracking ◽  
Grinding Machine

In cam grinding process, the grinding force changes with the change of cam contour, and its change leads to create the error of X-C linkage servo-tracking position, all of the factors reduce the cam the contour accuracy. To improve the accuracy of the cam profile, and research the effect of X-C axis servo tracking, the key vector of grinding force to the position is proposed, in which the factors have been considered including the grinding depth, curvature change, cam width, length and other effects. According to the mechanical analysis of cam and grinding wheel, a cam grinding XC-axis grinding force model is established. With the flat-bottomed follower cam as an example, the grinding force of X axis and C axis is calculated. The cam grinding experiment was conducted in the grinding machine, the tangential grinding force and normal grinding force were obtained and the model was verified. The grinding force mathematical model of X-C linkage provides the theoretical basis for the servo tracking position of X-C linkage grinding.

scholarly journals Model for Predicting the Micro-Grinding Force of K9 Glass Based on Material Removal Mechanisms

Micromachines ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 969
Author(s):  
Hisham Manea ◽  
Xiang Cheng ◽  
Siying Ling ◽  
Guangming Zheng ◽  
Yang Li ◽  
...  
Keyword(s):  
Optical Glass ◽  
High Surface ◽  
Chip Thickness ◽  
High Hardness ◽  
Industrial Applications ◽  
Grinding Force ◽  
Machining Accuracy ◽  
Force Model ◽  
Tool Diameter ◽  
K9 Glass

K9 optical glass has superb material properties used for various industrial applications. However, the high hardness and low fracture toughness greatly fluctuate the cutting force generated during the grinding process, which are the main factors affecting machining accuracy and surface integrity. With a view to further understand the grinding mechanism of K9 glass and improve the machining quality, a new arithmetical force model and parameter optimization for grinding the K9 glass are introduced in this study. Originally, the grinding force components and the grinding path were analyzed according to the critical depth of plowing, rubbing, and brittle tear. Thereafter, the arithmetical model of grinding force was established based on the geometrical model of a single abrasive grain, taking into account the random distribution of grinding grains, and this fact was considered when establishing the number of active grains participating in cutting Nd-Tot. It should be noted that the tool diameter changed with machining, therefore this change was taking into account when building the arithmetical force model during processing as well as the variable value of the maximum chip thickness amax accordingly. Besides, the force analysis recommends how to control the processing parameters to achieve high surface and subsurface quality. Finally, the force model was evaluated by comparing theoretical results with experimental ones. The experimental values of surface grinding forces are in good conformity with the predicted results with changes in the grinding parameters, which proves that the mathematical model is reliable.

Analysis on the Effects of Grinding Wheel Speed on Removal Behavior of Brittle Optical Materials

2016 ◽  
Author(s):  
Ping Li ◽  
Tan Jin ◽  
Zongfu Guo ◽  
Jun Yi ◽  
Meina Qu
Keyword(s):  
Surface Quality ◽  
Material Removal ◽  
Optical Materials ◽  
Chip Thickness ◽  
Ground Surface ◽  
Subsurface Damage ◽  
Wheel Speed ◽  
Grinding Wheel ◽  
Undeformed Chip Thickness ◽  
Grinding Processes

It is often desired to increase the machining rate while maintaining the desired surface and subsurface integrity during fabricating high-quality optical glass components. This paper proposed a high-speed high-efficiency low-damage grinding technology for machining brittle optical materials, which consists of three grinding processes: rough grinding, semi-finishing grinding and finishing grinding. Grinding characteristics is investigated with respect to grinding forces, specific cutting energy, surface roughness, ground surface quality, subsurface damage, and material removal mechanisms in grinding of fused silica optical glasses with this technology at the grinding speeds of up to 150 m/s. These indications are thoroughly discussed by contacting the undeformed chip thickness. The results indicate that the level of these indications are significantly improved with an increase in the wheel speed due to the decrease of the undeformed chip thickness. It is also found that the improvement of ground surface quality is limited when the wheel speed from 120 m/s increases to 150 m/s may be due to the influence of vibration caused by the higher wheel speed. For different grinding processes, these results are also substantially improved with the change of grinding conditions. It is found that the material removal mechanism is dominated by brittle fracture at rough and semi-finishing grinding processes, while ductile flow mode can be observed at the finishing grinding process. There are some differences between the experimental results and the previous predicted model of subsurface damage depth.

scholarly journals A New Grinding Force Model for Micro Grinding RB-SiC Ceramic with Grinding Wheel Topography as an Input

Micromachines ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 368 ◽  
Author(s):  
Zhipeng Li ◽  
Feihu Zhang ◽  
Xichun Luo ◽  
Xiaoguang Guo ◽  
Yukui Cai ◽  
...  
Keyword(s):  
Brittle Fracture ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Sic Ceramics ◽  
Grinding Force Model ◽  
Proposed Model ◽  
Wheel Topography ◽  
Grinding Wheel Topography ◽  
Force Components

The ability to predict the grinding force for hard and brittle materials is important to optimize and control the grinding process. However, it is a difficult task to establish a comprehensive grinding force model that takes into account the brittle fracture, grinding conditions, and random distribution of the grinding wheel topography. Therefore, this study developed a new grinding force model for micro-grinding of reaction-bonded silicon carbide (RB-SiC) ceramics. First, the grinding force components and grinding trajectory were analysed based on the critical depth of rubbing, ploughing, and brittle fracture. Afterwards, the corresponding individual grain force were established and the total grinding force was derived through incorporating the single grain force with dynamic cutting grains. Finally, a series of calibration and validation experiments were conducted to obtain the empirical coefficient and verify the accuracy of the model. It was found that ploughing and fracture were the dominate removal modes, which illustrate that the force components decomposed are correct. Furthermore, the values predicted according to the proposed model are consistent with the experimental data, with the average deviation of 6.793% and 8.926% for the normal and tangential force, respectively. This suggests that the proposed model is acceptable and can be used to simulate the grinding force for RB-SiC ceramics in practice.

scholarly journals Experimental Research on Material Removal Mechanism and Grinding Force of FeCoNiCrMo0.1 High Entropy Alloy (HEA)

2021 ◽  
Author(s):  
Ruchu Xu ◽  
Xuelong Wen ◽  
Yadong Gong ◽  
Xingchen Yu
Keyword(s):  
Material Removal ◽  
Grinding Force ◽  
Grinding Wheel ◽  
High Entropy Alloy ◽  
Force Model ◽  
Removal Mechanism ◽  
Material Removal Mechanism ◽  
Grinding Forces ◽  
High Entropy ◽  
Cbn Grinding Wheel

Abstract High entropy alloy (HEA) is an advanced alloy material, which has a wide application prospect due to its excellent properties. However, the material removal mechanism and change rule of grinding force of HEA in the grinding process have seldom been studied. The main work of this paper is that the material removal mechanism of the FeCoNiCrMo0.1 HEA is obtained by analyzing grinding debris and subsurface microstructure after grinding, the theoretical grinding force model of HEAs in plane grinding process is established on the basis of the force of a single abrasive grain, and the experimental verification is performed. According to the experimental results, the influences of different grinding parameters on grinding force are discussed, the influences of different types of grinding wheels on grinding force are analyzed, and the grinding forces generated by grinding different FeCoNiCr HEAs are compared. The results indicate that the material removal mechanism of FeCoNiCrMo0.1 HEA is the plastic removal. With the increase of grinding speed and the decrease of grinding depth and feed speed, both normal and tangential grinding forces decrease. Under the same grinding parameters, the grinding force produced by electroplated CBN grinding wheel is greater, followed by resin-bonded CBN grinding wheel and vitrified CBN grinding wheel. The grinding force produced by grinding FeCoNiCrAl0.1 HEA is lower than that produced by grinding FeCoNiCrMo0.1 HEA under the same grinding conditions. The calculated value of grinding force model is consistent with the experimental value, which can scientifically reflect the variation law of HEA grinding force.

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