Stability Prediction Model for Milling Process

In the process of milling thin-walled plate, chatter is one of the major limitations on productivity and part quality even for high speed and high precision milling machines. Therefore, it is necessary to avoid chatter with a suitable choice of cutting condition. This paper studies the dynamic stability models of milling the thin-walled plate by analyzing the geometrical relationship of cutting, and derives the mathematic expressions in theory. Moreover, this paper develops a three-dimensional lobes diagram of the spindle speed, the axial depth and the radial depth. Through the three-dimensional lobes, it is possible to choose the appropriate cutting parameters according to the dynamic behavior of the chatter system.

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Stability Prediction during Thin-Walled Workpiece High-Speed Milling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.69-70.428 ◽

2009 ◽

Vol 69-70 ◽

pp. 428-432 ◽

Cited By ~ 3

Author(s):

Qing Hua Song ◽

Yi Wan ◽

Shui Qing Yu ◽

Xing Ai ◽

J.Y. Pang

Keyword(s):

High Speed ◽

Dynamic Properties ◽

Removal Rate ◽

Cutting Parameters ◽

Milling Process ◽

Machining Process ◽

High Speed Milling ◽

Thin Walled ◽

Optimization Of Cutting Parameters ◽

Free Material

A method for predicting the stability of thin-walled workpiece milling process is described. The proposed approach takes into account the dynamic characteristics of workpiece changing with tool positions. A dedicated thin-walled workpiece representative of a typical industrial application is designed and modeled by finite element method (FEM). The workpiece frequency response function (FRF) depending on tool positions is obtained. A specific 3D stability chart (SC) for different spindle speeds and different tool positions is then elaborated by scanning the dynamic properties of workpiece along the machined direction throughout the machining process. The dynamic optimization of cutting parameters for increasing the chatter free material removal rate and surface finish is presented through considering the chatter vibration and forced vibration. The investigations are compared and verified by high speed milling experiments with flexible workpiece.

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High speed machining of the thin-walled aircraft constructions

Mechanik ◽

10.17814/mechanik.2017.8-9.105 ◽

2017 ◽

Vol 90 (8-9) ◽

pp. 726-729 ◽

Cited By ~ 3

Author(s):

Paweł Bałon ◽

Edward Rejman ◽

Robert Smusz ◽

Bartłomiej Kiełbasa

Keyword(s):

High Speed ◽

Cutting Speed ◽

Cutting Parameters ◽

Internal Stresses ◽

Depth Of Cut ◽

Machining Errors ◽

Radial Depth ◽

Thin Walled ◽

Machining Operations ◽

Optimization Of Cutting Parameters

Machining operations of thin-walled elements generate a lot of production process issues related to deformations and elastic and plastic displacements of the workpiece. Due to displacements of the milled workpiece, vibrations can occur, and thus, geometric errors may occur on surface in the structure of the workpiece. Furthermore, plastic deformation can also cause shape problems and be a source of internal stresses in the surface layer, which are highly difficult to remove and lead to deformation of the workpiece after machining. Consequently, this leads to an increase in the manufacturing costs of machining operations, especially of thin-walled elements, due to shortages and increased manufacturing time. It is recommended that multiple methods for minimizing machining errors be utilized to improve the quality of thin walled elements, such as: optimization of the machining strategy, increase of the cutting speed vc, optimization of cutting parameters, especially feed per blade fz, the radial depth of cut ae due to the minimization of the cutting force component perpendicular to the surface of the milled wall.

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Research on Cutting Force of Turn-Milling Based on Thin-Walled Blade

Advances in Materials Science and Engineering ◽

10.1155/2016/2638261 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Lida Zhu ◽

Baoguang Liu ◽

Xiaobang Wang ◽

Zhiwei Xu

Keyword(s):

Cutting Force ◽

Cutting Forces ◽

Metal Removal ◽

Cutting Parameters ◽

Milling Process ◽

Cutting Condition ◽

Deformation Properties ◽

Mechanism Research ◽

Thin Walled ◽

Turn Milling

Turn-milling is regarded as the milling of a curved surface while rotating the workpiece around its center point, which combines effectively the advantages of both turning and milling, wherein it allows for good metal removal with the difficult-to-cut thin-walled workpieces in aviation. The objective of the present work is to study cutting force by turn-milling in cutting condition. Aiming at the deformation properties of thin-walled blade, the predicted models of rigid cutting force and flexible cutting force with ball cutter are provided, respectively, in turn-milling process. The deformation values of blade and cutter are calculated, respectively, based on the engaged trajectory by using the iterative algorithm. The rigid and flexible cutting forces are compared and the influence degrees of cutting parameters on cutting forces are analyzed. These conclusions provide theoretical foundation and reference for turn-milling mechanism research.

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Cutting Parameters Optimization of High-Speed Milling of Thin-Walled Graphite Electrode

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.315-316.319 ◽

2006 ◽

Vol 315-316 ◽

pp. 319-323 ◽

Cited By ~ 3

Author(s):

Z.L. Hu ◽

Cheng Yong Wang ◽

L. Zhou ◽

H. Fu ◽

J. Chen

Keyword(s):

High Speed ◽

Graphite Electrode ◽

Cutting Parameters ◽

Parameters Optimization ◽

Main Process ◽

Cutting Depth ◽

High Speed Milling ◽

Radial Depth ◽

Thin Walled ◽

Cutting Parameters Optimization

Graphite electrode material has been extensively used for thin-walled electrode manufacturing, due to its typical brittleness, HSM becomes the main process method to obtain higher productivity and good surface finish. According to the structure characteristics of the thin-walled graphite electrode and the problems arising in its high-speed milling, through high-speed milling experiments, researches have been done into the effect of the main cutting parameters on cutting forces, which include cutting speed, feed per tooth, radial cutting depth, axial cutting depth, down or up milling. Finally, cutting parameters optimization strategies of high-speed milling of thin-walled graphite electrode aiming to obtain higher efficiency and high quality are presented as follows: down-cut mode, moderate radial depth of cut and flat endmill should be adopted in high-speed milling of graphite electrode.

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SURFACE ROUGHNESS OF MAGNESIUM ALLOY AZ91D IN HIGH SPEED MILLING

Jurnal Teknologi ◽

10.11113/jt.v78.9158 ◽

2016 ◽

Vol 78 (6-9) ◽

Cited By ~ 4

Author(s):

Mohd Shahfizal Ruslan ◽

Kamal Othman ◽

Jaharah A.Ghani ◽

Mohd Shahir Kassim ◽

Che Hassan Che Haron

Keyword(s):

Surface Roughness ◽

Magnesium Alloy ◽

Feed Rate ◽

High Speed ◽

Cutting Parameters ◽

Experimental Result ◽

Depth Of Cut ◽

Polishing Process ◽

High Speed Cutting ◽

Radial Depth

Magnesium alloy is a material with a high strength to weight ratio and is suitable for various applications such as in automotive, aerospace, electronics, industrial, biomedical and sports. Most end products require a mirror-like finish, therefore, this paper will present how a mirror-like finishing can be achieved using a high speed face milling that is equivalent to the manual polishing process. The high speed cutting regime for magnesium alloy was studied at the range of 900-1400 m/min, and the feed rate for finishing at 0.03-0.09 mm/tooth. The surface roughness found for this range of cutting parameters were between 0.061-0.133 µm, which is less than the 0.5µm that can be obtained by manual polishing. Furthermore, from the S/N ratio plots, the optimum cutting condition for the surface roughness can be achieved at a cutting speed of 1100 m/min, feed rate 0.03 mm/tooth, axial depth of cut of 0.20 mm and radial depth of cut of 10 mm. From the experimental result the lowest surface roughness of 0.061µm was obtained at 900 m/min with the same conditions for other cutting parameters. This study revealed that by milling AZ91D at a high speed cutting, it is possible to eliminate the polishing process to achieve a mirror-like finishing.

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Development of a machining simulator considering machine behaviour

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/095440503322420269 ◽

2003 ◽

Vol 217 (9) ◽

pp. 1333-1339 ◽

Cited By ~ 13

Author(s):

A Dugas ◽

J J Lee ◽

M Terrier ◽

J Y Hascoët

Keyword(s):

High Speed ◽

Dynamic Behaviour ◽

Three Dimensional ◽

Milling Process ◽

High Speed Machining ◽

Tracking Errors ◽

Tool Paths ◽

Milling Operation ◽

Dynamic Errors ◽

Tool Deflections

High-speed machining gives much potential for increasing the efficiency of the milling operation, but it requires very careful preparation for the milling process to use this potential. A machining simulator has been developed that can analyse dynamic errors due to tool deflections and machine dynamic behaviour using a three-dimensional solid simulation model. This kind of simulator would be a useful tool to apply in high-speed machining where it is necessary to obtain very well prepared part programs considering dynamic errors as well as geometrical errors. In this short communication, an algorithm will be introduced to estimate the dynamic errors caused by machine dynamic behaviour. Specifically, this algorithm predicts real feed rates and tracking errors considering the limits of numerical controllers and machine tools. The efficiency of the algorithm has been verified through several experiments with various tool paths. In addition, the algorithm has been integrated into the machining simulator. Some results obtained from the machining simulator concerning the estimation of tracking errors will be reported.

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Aerodynamic Characteristics Analysis of High-Speed Train on Cutting under Crosswinds

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.300-301.62 ◽

2013 ◽

Vol 300-301 ◽

pp. 62-67

Author(s):

Kun Ye ◽

Ren Xian Li

Keyword(s):

High Speed ◽

Three Dimensional ◽

Aerodynamic Characteristics ◽

High Speed Train ◽

Aerodynamic Forces ◽

Cutting Depth ◽

Cutting Slope ◽

Characteristics Analysis ◽

Relationship Of ◽

The Relationship

Cutting is an effective device to reduce crosswind loads acting on trains. The cutting depth, width and gradient of slope are important factors for design and construction of cutting. Based on numerical analysis methods of three-dimensional viscous incompressible aerodynamics equations, aerodynamic side forces and yawing moments acting on the high-speed train, with different depths and widths of cutting，are calculated and analyzed under crosswinds，meanwhile the relationship of the gradient of cutting slope and transverse aerodynamic forces acting on trains are also studied. Simulation results show that aerodynamic side forces and yawing moments acting on the train（the first, middle and rear train）decrease with the increase of cutting depth. The relationship between transverse forces (moments) coefficients acting on the three sections and the cutting depth basically is the three cubed relation. The bigger is cutting width，the worse is running stability of train. The relationship between yawing moments coefficients acting each body of the train and the cutting width approximately is the three cubed relation. The transverse Aerodynamic forces decreased gradually with the increase of the gradient of cutting slope, the relationship between yawing moments coefficients acting each body of the train and the gradient of cutting slope basically is the four cubed relation.

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

Advances in Mechanical Engineering ◽

10.1177/1687814019853188 ◽

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.

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