An autonomous optimization of tool paths in canned cycles for end milling

Abstract The analysis of the surface topography in ball end milling is an objective studied by many researchers, several methods were used and many combinations of cutting conditions and machining errors are considered. In the milling tool paths the trajectories presents a points of changing direction where the tool decelerates before and accelerates after respecting the velocity profiles of the machine. In this paper, we propose experimental investigations of the effect of the kinematic behavior of the machine tool on the surface quality. A poor topography and roughness are remarked on the deceleration and the acceleration zones compared to the stationary zone.

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A Simulation Study on the End Milling Operation with Multiple Process Steps of Aeronautical Frame Monolithic Components

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.66-68.569 ◽

2011 ◽

Vol 66-68 ◽

pp. 569-572

Author(s):

Hai Chao Ye ◽

Guo Hua Qin ◽

Cong Kang Wang ◽

Dong Lu

Keyword(s):

End Milling ◽

Machining Process ◽

Deformation Analysis ◽

Tool Paths ◽

Milling Operation ◽

Multiple Process ◽

Monolithic Components ◽

Milling Forces ◽

The Given

Machining deformation has always been a bottleneck issue in the manufacturing field of aeronautical monolithic components. On the base of finite element method, the effect of the process steps and tool paths on the workpiece stiffness and the redistribution of residual stress in the machining process of aeronautical frame monolithic component was investigated under the given fixturing scheme. Thus, the prediction of the workpiece deformation can be carried out in reason. The proposed simulation approach to deformation analysis can be used to observe the true characteristic of milling forces and machining deformations. Therefore, the proposed method can supply the theoretical basis for the determination of the optimal process parameters.

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Micromachining of CP-Titanium on a Desktop Machine - Study on Bottom Surface Quality in Micro End Milling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.769.53 ◽

2013 ◽

Vol 769 ◽

pp. 53-60 ◽

Cited By ~ 7

Author(s):

Ingo Gustav Reichenbach ◽

Martin Bohley

Keyword(s):

Surface Quality ◽

Functional Performance ◽

End Milling ◽

Plane Surface ◽

Bottom Surface ◽

Influence Of Process Parameters ◽

Tool Paths ◽

Micro End Milling ◽

End Mills ◽

Micro Features

With the ever-growing demand for micro products, the influence of micro-features and the functional performance of component surfaces represent a high economical potential. A competitive process for the manufacture of micro products is using micro end mills and a desktop milling machine. Since the topography of machined surfaces affects e.g. the wetting interaction or the bacterial cell adhesion, all relevant finishing steps such as the generation of a plane surface parallel to the machining table and the structuring with micro end mills have to be concerned in order to create functional surfaces. In this paper the generation of plane surfaces and chosen tool paths is described first and then the use of ultra-small micro end mills for slot milling in cp-titanium and the influence of process parameters on bottom surface quality is discussed.

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A Study on the Machining Characteristics of Curved Workpiece using Laser Assisted Milling with Different Tool Paths in Inconel 718

10.20944/preprints201810.0685.v1 ◽

2018 ◽

Author(s):

Eun Jung Kim ◽

Choon Man Lee

Keyword(s):

Inconel 718 ◽

End Milling ◽

Three Dimensional ◽

Depth Of Cut ◽

Finite Elements Analysis ◽

Laser Assisted Machining ◽

Specific Strength ◽

Tool Paths ◽

Machining Characteristics ◽

Conventional Machining

Difficult-to-cut materials are being increasingly used in many industries because of their superior properties, including high corrosion resistance, heat resistance and specific strength. However, these same properties make the materials difficult to machine using conventional machining techniques. Laser-assisted milling (LAM) is one of the effective methods for machining difficult-to-cut materials. In laser-assisted milling machining occur after the workpiece is locally preheated using a laser heat source. Laser assisted machining has been studied by many researchers on flat workpiece or micro end-milling. However, there is no research on the curved shape using laser assisted milling. This study investigated the use of laser assisted milling to machine a three-dimensional curved shape workpiece based on NURBS. A machining experiment was performed on Inconel 718 using different tool paths (ramping, contouring) under various machining conditions. Finite elements analysis was conducted to determine the depth of cut. Cutting force, specific cutting energy and surface roughness characteristics were measured, analyzed and compared for conventional and LAM machining. LAM significantly improved these machining characteristics, compared to conventional machining. There results can be applied to the laser-assisted machining of various three-dimensional shapes.

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A Study on the Machining Characteristics of Curved Workpiece Using Laser-Assisted Milling with Different Tool Paths in Inconel 718

Metals ◽

10.3390/met8110968 ◽

2018 ◽

Vol 8 (11) ◽

pp. 968 ◽

Cited By ~ 5

Author(s):

Eun Kim ◽

Choon Lee

Keyword(s):

Inconel 718 ◽

End Milling ◽

Three Dimensional ◽

Depth Of Cut ◽

Finite Elements Analysis ◽

Specific Strength ◽

Tool Paths ◽

Micro End Milling ◽

Machining Characteristics ◽

Conventional Machining

Difficult-to-cut materials are being increasingly used in many industries because of their superior properties, including high corrosion resistance, heat resistance and specific strength. However, these same properties make the materials difficult to machine using conventional machining techniques. Laser-assisted milling (LAM) is one of the effective method for machining difficult-to-cut materials. In laser-assisted milling, the machining occur after the workpiece is locally preheated using a laser heat source. Laser-assisted milling has been studied by many researchers on flat workpiece or micro end-milling. However, there is no research on the curved shape using laser assisted milling. This study investigated the use of laser-assisted milling to machine a three-dimensional curved shape workpiece based on NURBS (Non-uniform rational b-spline). A machining experiment was performed on Inconel 718 using different tool paths (ramping, contouring) under various machining conditions. Finite elements analysis was conducted to determine the depth of cut. Cutting force, specific cutting energy and surface roughness characteristics were measured, analyzed and compared for conventional and LAM machining. LAM significantly improved these machining characteristics, compared to conventional machining. There results can be applied to the laser-assisted milling of various three-dimensional shapes.

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Cutter/Workpiece Engagement Feature Extraction from Solid Models for End Milling

Journal of Manufacturing Science and Engineering ◽

10.1115/1.1948395 ◽

2004 ◽

Vol 128 (1) ◽

pp. 249-260 ◽

Cited By ~ 23

Author(s):

Derek Yip-Hoi ◽

Xuemei Huang

Keyword(s):

Feature Extraction ◽

End Milling ◽

Solid Modeling ◽

Tool Paths ◽

Part Geometry ◽

Solid Models ◽

Connected Set ◽

End Mills ◽

Moderate Complexity ◽

Different Diameters

Accurate process modeling requires the calculation of cutter/workpiece engagement (CWE) geometry. This is challenging when the geometry of the workpiece is changing unpredictably as is the case for most machined components of moderate complexity. Solid modelers are increasingly being considered as a computational engine for performing these calculations. This is largely due to increased robustness and computing efficiency that is evolving within this technology. The vast majority of reported research using solid modelers focuses on the domain of 212D machining with flat end mills. While significant there remain restrictions in the types of in-process workpiece geometry that can be processed with these approaches. In particular, they assume a constant axial engagement for a connected set of tool paths. This assumption cannot be made when the initial workpiece geometry is nonrectangular prismatic stock, when multiple setups are machined and when tool changes introduce tools of different diameters. In these cases the depth of engagement can vary over a single rotation of the cutter even though there is no axial feed motion. In this paper a solid modeling based solution is presented for calculating CWE geometry when multiple setups and tool changes are considered. Orthogonal setups and flat end mills are assumed so as to preclude cutter engagement on inclined workpiece faces. Intersections between a semi-cylinder representing the cutting tool and the workpiece are performed so as to generate the CWE geometry. Cutter Engagement Features (ceF) are used to characterize this geometry. Several classes of ceFs are defined to support this approach. The process of identifying ceFs is presented as a feature extraction problem. Algorithms for ceF extraction and parametrization are provided in this paper and validated using a test part. This is a new application for features which have traditionally been used to define final part geometry or in-process geometry between material removal steps. The results obtained validate the extraction algorithms presented. This work also extends the capabilities of solid modeling techniques for calculating CWE geometry.

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Constant Scallop-height Machining of Free-form Surfaces

Journal of Engineering for Industry ◽

10.1115/1.2901938 ◽

1994 ◽

Vol 116 (2) ◽

pp. 253-259 ◽

Cited By ~ 187

Author(s):

K. Suresh ◽

D. C. H. Yang

Keyword(s):

Tool Path ◽

End Milling ◽

Free Form ◽

Machining Time ◽

Scallop Height ◽

Location Data ◽

Tool Paths ◽

Novel Approach ◽

Constant Scallop Height ◽

Free Form Surfaces

A novel approach for the NC tool-path generation of free-form surfaces is presented. Traditionally, the distance between adjacent tool-paths in either the Euclidean space or in the parametric space is kept constant. Instead, in this work, the scallop-height is kept constant. This leads to a significant reduction in the size of the CL (cutter location) data accompanied by a reduction in the machining time. This work focuses on the zig-zag (meander) finishing using a ball-end milling cutter.

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Improving Rough Cutting Efficiency for Machining of Impellers

Volume 4: Turbo Expo 2004 ◽

10.1115/gt2004-54025 ◽

2004 ◽

Cited By ~ 1

Author(s):

Der-Min Tsay ◽

Chien-Wen Chen

Keyword(s):

End Milling ◽

Geometric Model ◽

Production Costs ◽

Cnc Milling ◽

Rough Machining ◽

Tool Paths ◽

Cnc Milling Machine ◽

Computer Numerically Controlled ◽

Step Interval ◽

Time Required

A procedure that can be used to generate rough cutting tool paths with minimized variations of material removal rates (MRRs) is developed for 5-axis ball end milling of centrifugal compressor impellers. Based on the geometric model of impellers, the detailed processes in finding the cutter contact (CC) points with equal spacing for step interval between two adjacent tool paths and a constant depth between two neighboring cutting layers are presented. The developed system can considerably improve productivity and lower production costs in rough machining since the time required can be reduced by minimizing the waste tool paths. Simulation and machining tests by a 5-axis computer numerically controlled (CNC) milling machine are performed to illustrate the procedure and its advantages.

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Determination Method of Locations and Postures of Cutting Tool for 5-Axis Machining Based on Intuition and Minimum Cusp Height

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.516.96 ◽

2012 ◽

Vol 516 ◽

pp. 96-101

Author(s):

Hideki Aoyama ◽

Yumiko Suzuki ◽

Noriaki Sano

Keyword(s):

Cutting Tool ◽

End Milling ◽

Basic System ◽

End Mill ◽

Machining Processes ◽

Tool Paths ◽

Virtual Machining ◽

Section Shape ◽

Cusp Height ◽

Cam Systems

Currently used CAM systems for 5-axis machining can determine tool paths with collision-free tool postures. However, the algorithm implemented in the CAM systems sometimes generates un-optimum tool paths and postures from the viewpoint of machining processes and machine tool operation. This study proposes two methods to determine tool paths and tool postures for 5-axis machining based on the viewpoints of human intuition and minimum cusp height for resolving the problems. A method is developed for inputting the positions and postures of a cutting tool when executing virtual machining. In the execution of virtual machining, a virtual cutting tool can be intuitively moved by a haptic device to determine the desired locations and postures of the cutting tool. By using the system, the tool locations and tool postures to machine complicated shapes with overhang can be easily determined based on the operators intuition. Another method is for determining tool postures for making minimum cusp height by matching the cutting edge of a flat end-mill to the cross-section shape at a point on surfaces to be machined. A basic system to determine the tool postures based on making minimum cusp height was developed. The cusp height on the surfaces generated by the basic system was smaller than the height generated by 3-axis ball-end milling.

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Optimum end milling tool path and machining parameters for micro Laval nozzle manufacturing

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

10.1177/0954405415608601 ◽

2015 ◽

Vol 231 (10) ◽

pp. 1703-1712 ◽

Cited By ~ 4

Author(s):

Yukui Cai ◽

Zhanqiang Liu ◽

Zhenyu Shi ◽

Qinghua Song ◽

Yi Wan

Keyword(s):

Surface Roughness ◽

Laval Nozzle ◽

Tool Path ◽

Cutting Tool ◽

End Milling ◽

Cutting Parameters ◽

Machining Parameters ◽

Performance Parameters ◽

Tool Paths ◽

Milling Tool

Cutting tool path has significant effects on the performance of micro nozzles manufactured by micro machining. Different tool paths induced different directions of surface roughness. As for it, the manufacturers need to obtain optimal cutting tool path and cutting parameters. In this article, optimum machining parameters for the fabrication of micro Laval nozzle with two different end milling tool paths are presented. First, surface roughness models for different types of cutting tool paths are proposed. A case of machined nozzle surface is then given to verify the applicability of the developed roughness model. Second, theoretical profile geometries for the Laval nozzle to be manufactured are designed. Third, the influences of surface roughness on the nozzle performance parameters including total pressure, average outlet velocity and thrust are investigated through computational fluid dynamic analysis. Simulated performance parameters are contrasted with their theoretical values. It is found that for different tool paths, the nozzle of axial tool path has larger total pressure and average outlet velocity than that of circular tool path. Moreover, with surface roughness increasing, thrust decreases obviously when surface roughness Rz is larger than 4.8 μm. Micro end milling experiments based on axial tool path are then performed, and the optimum cutting parameters are obtained. Finally, a nozzle was manufactured with the axial tool path as well as the optimized cutting parameters.

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