Chatter Stability Model of Micro-Milling With Process Damping

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
Xiaoliang Jin ◽  
Yusuf Altintas
Keyword(s):  
Finite Element ◽  
Cutting Speed ◽  
Rake Angle ◽  
Micro Milling ◽  
Piezo Actuator ◽  
Chatter Stability ◽  
Line Field ◽  
Process Damping ◽  
Aisi 1045 Steel ◽  
1045 Steel

This paper presents the prediction of cutting forces and chatter stability of micro-milling operations from the material's constitutive flow stress and structural dynamics of the micro-end mill. The cutting force coefficients are identified either using previously presented slip-line field or finite element methods by considering the effects of chip size, cutting edge radius, rake angle and cutting speed. The process damping caused by the plowing of round edge is modeled by finite element method. The frequency response function of the fragile micro-mill is measured through specially devised piezo actuator mechanism. Dynamic model of micro-milling with the velocity dependent process damping mechanism is presented, and the chatter stability is predicted in frequency domain. The proposed models have been experimentally verified in micro-milling of AISI 1045 steel.

Experimental Study and Theory Prediction on Adiabatic Shear Critical Conditions of Hardened AISI 1045 Steel

2011 ◽  
Vol 189-193 ◽  
pp. 3061-3065
Author(s):  
Guo He Li ◽  
Tie Li Qi ◽  
Yu Jun Cai ◽  
Hong Jun Wang
Keyword(s):  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Rake Angle ◽  
Adiabatic Shear ◽  
Cutting Conditions ◽  
Critical Conditions ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel ◽  
Cutting Experiments

Orthogonal cutting experiments of hardened AISI1045 steel(45HRC) are performed to investigate the influence of cutting conditions on adiabatic shear which occurs in the process of chip formation of many materials. It is found that the cutting speed, cutting depth and rake angle all have influence on adiabatic shear and there is a critical cutting speed at which the adiabatic shear appears. By metallurgical observation, the critical cutting speed under different cutting depths and rake angles are given. A model based on linear pertubation analysis is used to predict the adiabatic shear critical cutting conditions of hardened AISI 1045 steel. The comparison of prediction results and that of expriments shows that this prediction model is valid.

Enhancement of Machinability of AISI1045 Steel Using Molybdenum Disulphide as a Solid Lubricant

2006 ◽  
Author(s):  
N. Suresh Kumar Reddy ◽  
P. Venkateswara Rao
Keyword(s):  
Solid Lubricant ◽  
Cutting Speed ◽  
Rake Angle ◽  
Molybdenum Disulphide ◽  
Nose Radius ◽  
Radial Rake Angle ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Set Up ◽  
1045 Steel

The heat produced during machining is critical in terms of workpiece quality. So, effective control of heat generated at the cutting zone is essential to ensure the workpiece quality in machining, which can be achieved by using coolants. As the coolants are relatively inaccessible to the machining zone due to the typical nature of the process, it has been attempted to study the performance of machining of AISI 1045 steel using molybdenum disulphide as a solid lubricant in the present work. The experimental set up (solid lubricant powder feeder) for molybdenum disulphide assisted machining was designed and built. After ensuring the set up for proper lubrication, experiments were conducted to see the influence of tool geometry (radial rake angle and nose radius) and cutting conditions (cutting speed and feed rate) on the considered machining response while machining AISI 1045 steel. In order to compare the performance of molybdenum disulphide with that of wet machining, the same set of conditions that were conducted with wet condition repeated using molybdenum disulphide as solid lubricant. Results indicate that there is a considerable improvement in the performance of milling AISI 1045 steel using molybdenum disulphide as a solid lubricant when compared with wet machining in terms of surface finish and chip thickness. The experimental results of this work will be used to obtain the relationship between cutting speed, feed rate, radial rake angle, and nose radius on the machining response i.e. surface roughness by modeling.

Modeling of Stresses and Temperature in Turning Using Finite Element Method

2013 ◽  
Vol 307 ◽  
pp. 174-177 ◽  
Author(s):  
Kuldip Singh Sangwan ◽  
Girish Kant ◽  
Aditya Deshpande ◽  
Pankaj Sharma
Keyword(s):  
Finite Element ◽  
Cutting Forces ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Machining Parameters ◽  
Effective Stresses ◽  
Wide Range ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel

This paper focuses on finite element modeling of orthogonal cutting process of AISI 1045 steel using Modified Johnson Cook (MJC) as constitutive material flow model under various machining parameters. Finite element solutions of cutting forces, effective stresses and temperature are obtained for a wide range of cutting speeds and feeds. The effect of feed and cutting speed on cutting forces, effective stresses and temperature has been studied over a wide range of values. Percentage variation of each is also studied to predict co-relation with the different machining parameters.

Experimental investigation of a slip-line field model for a worn cutting tool

2013 ◽  
Vol 228 (8) ◽  
pp. 1398-1404 ◽  
Author(s):  
Alper Uysal ◽  
Erhan Altan
Keyword(s):  
Wear Rate ◽  
Slip Line ◽  
Field Model ◽  
Cutting Tool ◽  
Flank Wear ◽  
Cutting Speed ◽  
Chip Thickness ◽  
Rake Angle ◽  
Uncut Chip Thickness ◽  
Line Field

In this study, the slip-line field model developed for orthogonal machining with a worn cutting tool was experimentally investigated. Minimum and maximum values of five slip-line angles ( θ1, θ2, δ2, η and ψ) were calculated. The friction forces that were caused by flank wear land, chip up-curl radii and chip thicknesses were calculated by solving the model. It was specified that the friction force increased with increase in flank wear rate and uncut chip thickness and it decreased a little with increase in cutting speed and rake angle. The chip up-curl radius increased with increase in flank wear rate and it decreased with increase in uncut chip thickness. The chip thickness increased with increase in flank wear rate and uncut chip thickness. Besides, the chip thickness increased with increase in rake angle and it decreased with increase in cutting speed.

Finite Element and Experimental Analysis of Edge Defects Formation during Orthogonal Cutting of SiCp/Al Composites

2012 ◽  
Vol 500 ◽  
pp. 146-151 ◽  
Author(s):  
Ning Hou ◽  
Li Zhou ◽  
Shu Tao Huang ◽  
Li Fu Xu
Keyword(s):  
Finite Element ◽  
Chip Formation ◽  
Defect Formation ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Rake Angle ◽  
Critical Transition ◽  
Cutting Depth ◽  
Edge Defect ◽  
Edge Defects

In this paper, a finite element method was used to dynamically simulate the process of the edge defects formation during orthogonal cutting SiCp/Al composites. The influence of the cutting speed, cutting depth and rake angle of the PCD insert on the size of the edge defects have been investigated by using scanning electron. According to the simulated results, it can be provided that the cutting layer material has an effect on transfer stress and hinder the chip formation in the critical transition stage, and the critical transition point and distance are defined in this stage. The negative shear phenomenon is found when the chip transit to the edge defects in the flexure deformation stage, so the process of the chip formation is the basis of the edge defects formation. In addition, the relationship between the nucleation and propagation direction of the crack and the variation of the edge defect shape on the workpiece was investigated by theory, and it found that the negative shear angle formation is the primary cause of the edge defect formation. A mixed mode crack is found in the crack propagation stage. The sizes of edge defects were measured by the experiment and simulation, and the edge defect size decrease with the increasing of tool rake angle, while increase with increasing cutting depth and cutting speed.

Chatter Stability Prediction of Cutting Process With Process Damping Utilizing Finite Element Analysis

2020 ◽  
Author(s):  
Norikazu Suzuki ◽  
Tomoki Nakanomiya ◽  
Eiji Shamoto
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Vibration Amplitude ◽  
Cutting Process ◽  
Force Model ◽  
Chatter Stability ◽  
Chatter Vibration ◽  
Damping Force ◽  
Element Analysis ◽  
Process Damping

Abstract This paper presents a new approach to predict chatter stability in cutting considering process damping. Traditional chatter stability analysis methods enable to predict stable or unstable conditions. Under unstable conditions, the chatter vibration can increase theoretically infinitely. However, chatter vibration is damped at a certain amplitude in real process due to process damping, i.e., the cutting process is stabilized by means of tool flank face contact to the machined surface. In order to consider the influence of the process damping, a simple process damping force model is introduced. The process damping force is assumed to be proportional to the structural displacement. The process damping coefficient is a function of the vibration amplitude and the wavelength. In order to identify the coefficients, a series of finite element analysis is conducted in the present study. Identified coefficients are introduced into the conventional zero-order-solution in frequency domain. The proposed model calculates chatter stability limit assuming process damping with finite amplitude. Hence, this analysis enables to estimate the amplitude-dependent quasi-stable conditions. Analytical results for thee face turning operation demonstrated influence of process damping effect on resultant vibration amplitude quantitatively.

Finite Element Simulation and Experimental Research on Micro-Milling Process of Titanium Alloy

2012 ◽  
Vol 522 ◽  
pp. 245-248 ◽  
Author(s):  
Hai Tao Liu ◽  
Ya Zhou Sun ◽  
De Bin Shan ◽  
Yan Quan Geng
Keyword(s):  
Finite Element ◽  
Titanium Alloy ◽  
Finite Element Simulation ◽  
Large Scale ◽  
Simulation Analysis ◽  
Cutting Speed ◽  
Micro Milling ◽  
Element Analysis ◽  
Element Simulation ◽  
Cutting Heat

There are lots of titanium alloy parts which have large-scale micro-structures in astronautic structure and medical implants, so the micro milling becomes one of the effective processing methods in getting the surface micro-structure. Because the titanium alloy has high caking property in processing, it needs a research on the cutting heat and force in order to get better machining precision and surface quality. According to the finite element theory in elastic and plasticity, the influence of cutting speed to the cutting heat and force is got by finite element simulation analysis to the titanium material TC4 in cutting process. It can get the simulation results of cutting heat and force in the micro milling processing by finite element analysis, and then compared, the basic influence which the cutting speed to the cutting heat and force is got. The correctness of the result is checked through cutting experiments.

Tool tip cutting specific energy prediction model and the influence of machining parameters and tool wear in milling

2020 ◽  
Vol 234 (10) ◽  
pp. 1346-1354 ◽  
Author(s):  
Guoyong Zhao ◽  
Yu Su ◽  
Guangming Zheng ◽  
Yugang Zhao ◽  
Chunxiao Li
Keyword(s):  
Tool Wear ◽  
Prediction Model ◽  
Specific Energy ◽  
Machine Tools ◽  
Cutting Speed ◽  
Machining Parameters ◽  
Cutting Depth ◽  
Energy Prediction ◽  
Aisi 1045 Steel ◽  
1045 Steel

Most of the existing energy-consumption models of machine tools are related to specific machine components and hence cannot be applied to other machine tools with different specifications. In order to help operators optimize machining parameters for improving energy efficiency, the tool tip cutting specific energy prediction model based on machining parameters and tool wear in milling is developed, which is independent of the standby power of machine tools and the spindle no-load power. Then, the prediction accuracy of the proposed model is verified with dry milling AISI 1045 steel experiments. Finally, the influence of machining parameters and tool wear on tool tip cutting specific energy is studied. The developed model is independent of machine components, so it can reveal the influence of machining parameters and tool wear on tool tip cutting specific energy. The tool tip cutting specific energy reduces with the increase in the cutting depth, side cutting depth, feed rate, and cutting speed, while increases linearly as the tool wears gradually. The research results are helpful to formulate efficient and energy-saving processing schemes on various milling machines.

Finite Element Modeling of Chip Formation in the Domain of Negative Rake Angle Cutting

2003 ◽  
Vol 125 (3) ◽  
pp. 324-332 ◽  
Author(s):  
Y. Ohbuchi ◽  
T. Obikawa
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Chip Thickness ◽  
Rake Angle ◽  
Undeformed Chip Thickness ◽  
Element Modeling ◽  
Single Grain ◽  
Serrated Chips

A thermo-elastic-plastic finite element modeling of orthogonal cutting with a large negative rake angle has been developed to understand the mechanism and thermal aspects of grinding. A stagnant chip material ahead of the tool tip, which is always observed with large negative rake angles, is assumed to act like a stable built-up edge. Serrated chips, one of typical shapes of chips observed in single grain grinding experiment, form when analyzing the machining of 0.93%C carbon steel SK-5 with a rake angle of minus forty five or minus sixty degrees. There appear high and low temperature zones alternately according to severe and mild shear in the primary shear zone respectively. The shapes of chips depend strongly on the cutting speed and undeformed chip thickness; as the cutting speed or the undeformed chip thickness decreases, chip shape changes from a serrated type to a bulging one to a wavy or flow type. Therefore, there exists the critical cutting speed over which a chip can form and flow along a rake face for a given large negative rake angle and undeformed chip thickness.

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