볼엔드밀링의 비절삭 에너지 해석

이영문(Young-Moon Lee),배대원(Dae-won Bae),김선일(Sun-Il Kim),황근식(keun-sik Hwang),손성필(Sung-Pil Son),박건우(Geon-Woo Park) 한국기계가공학회 2006 한국기계가공학회 춘추계학술대회 논문집 Vol.2006 No.-

In Ball end milling processes, characterized by use of rotating tools, the underformed chip volume varies periodically with the phase change of tool. In current study, as a new approach to analyze shear behaviors in the shear plane and chip-tool friction behaviors in the chip-tool contact region during an ball end milling process. In this approach, ball end milling process is transformed into an equivalent oblique cutting process. Experimental investigations for two sets of cutting tests i.e.. ball end milling and the equivalent oblique cutting tests were performed to verify the presented model.

High-speed milling of Inconel 625 alloy using carbide ball end mills

Kazumasa Kawasaki 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

Inconel 625 alloy has advantageous properties, such as heat resistance and corrosion resistance, which make it a suitable material in aerospace, energy, and marine industries. However, it is also difficult-to-machine because of factors such as work hardening, low thermal conductivity, and high tool affinity. Therefore, the problems of tool wear, chipping, and adhesion often occur in milling of Inconel 625 alloy using end mills. We conducted experiments on the cutting of Inconel 625 alloy by high-speed milling using carbide ball end mills to investigate the tool wear, chipping, and adhesion under three spindle revolution speeds and two feed rates, and determine the optimal cutting conditions. The effects of spindle revolution speed on the tool and workpiece were clarified, and the optimal speed was established to achieve long tool life.

Ball End Mill—Tool Radius Compensation of Complex NURBS Surfaces for 3-Axis CNC Milling Machines

Zhaoqin Wang,Xiaorong Wang,Yusen Wang,Ruijun Wang,Manyu Bao,Tiesong Lin,Peng He 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.8

In order to extend the 2D-TRC (tool radius compensation) function of 3-axis CNC milling machines to ball end mills (BEMs), a new TRC named BEM-TRC is proposed to achieve successful milling of complex surfaces without over-cut. The implementation of the BEM-TRC for complex surfaces depicted in NURBS model is divided into three steps. The first one is to search the cutting point (CP) on a NURBS surface using equi-arc length interpolation in u or v direction. The second one is to accomplish BEM-TRC at the CP through offsetting the CP to the cutter center point (CCP) of a BEM along the normal vector at CP. The third one is to compute the cutter location point (CLP) of the BEM according to the BEM-CCP. The simulation and experiment verifies that the BEM-TRC is feasible and effective, and can avoid over-cut phenomenon successfully. The BEM-TRC extends the ability of the traditional 2D-TRC function, and makes 3-axis CNC milling machines to accomplish the milling process of complex NURBS surfaces.

An innovative CAD-based simulation of ball-end milling in microscale

Vakondios, Dimitrios G.,Kyratsis, Panagiotis Techno-Press 2020 Advances in computational design Vol.5 No.1

As small size and complex metal machining components demand increases, cutting processes in microscale become necessary. Ball-end milling is a commonly used finishing process, which nowadays can be applied in the microscale size. Surface quality and dimensional accuracy are two basic parameters that affect small size components in their assembly and functionality. Thus, good quality can be achieved by optimizing the cutting conditions of the procedure. This study presents a 3D simulation model of ball-end milling in microscale developed in a commercial CAD software and its optical and computing results. These carried out results are resumed to surface topomorphy, surface roughness, chip geometry and cutting forces calculations that arising during the cutting process. A great number of simulations were performed in a milling machine centre, applying the discretized kinematics of the procedure and the final results were compared with measurements of Al7075-T651 experiments.

Micro-texture design criteria for cemented carbide ball-end milling cutters

Shucai Yang,Tianjiao Wang,Wei Ren,Shuai Su 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.1

Given the serious work hardening phenomenon, high chemical activity, severe tool wear, and poor workpiece surface quality during the cutting of titanium alloys, placing micro-texture on the tool surface decreases the tool-chip contact area and friction and plays the role of wear resistance and friction reduction. In order to improve the cutting performance of cutting tools, the present study examins the effect of micro-texture parameters of a cemented carbide ball-end milling cutter on cutting force, tool wear, and workpiece surface roughness and establishes a regression analysis model via regression analysis. We consider the cutting performance of a cemented carbide micro-texture ball-end milling cutter as an evaluation standard. A genetic algorithm is applied to the multi-objective optimization of micro-texture parameters, and a regression analysis model of micro-texture design criteria is established. This provides a standardised reference to select standard micro-texture parameters in the design and preparation of a cemented carbide micro-texture ball-end milling cutter.

Influence of Tool Posture and Position on Stability in Milling with Parallel Kinematic Machine Tool

Muizuddin Azka,Keiji Yamada,Mahfudz Al Huda,Ryutaro Tanaka,Katsuhiko Sekiya 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.12

This paper investigated the machining stability influenced by tool posture and position in ball-end milling with parallel kinematic machine tool (PKM). Initially, the geometric structure was identified, and the machinery stiff ness was measured by impulse respond method at several positions with four tool postures. Then, the milling tests were conducted on fl at work surface using a ball-end mills. Cutting force and acceleration signals of milling tests were measured by three-axis dynamometer and accelerometer. Furthermore, these signals were analyzed by using Fast-Fourier transform and Hilbert–Huang transform (HHT). The results showed that the length of arm change with tool posture, where the machinery stiff ness decreased with the total length of arms for any tool position. The experimental results also demonstrated the machining stability varied with tool posture; the trend of stability corresponds with the machinery stiff ness. The vibration analysis by HHT presented the increasing of power level in the time–frequency plot when the length of arm increase during milling process. Therefore, the geometric influence must be considered to support process planning on the PKM.

Principle and Application of the Ball End Mill: Tool Radius Compensation for NURBS Curve Swept Surfaces Based on 3-Axis CNC Milling Machines

Zhaoqin Wang,Xiaorong Wang,Xiaoqin Liu,Yusen Wang,Chengyu Li,Tiesong Lin,Peng He 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.9

Common 3-axis CNC milling machines are generally equipped with 2D tool radius compensation (2D-TRC), which can realize TRC function for the contours in three basic planes when flat end mills are used. The 2D-TRC function makes engineers to program according to the actual contour of a part, and avoids over-cut phenomenon. Unfortunately, the 2D-TRC is unsuitable for ball end mills (BEMs), especially in the situation of milling complex curves or surfaces. In this work, a new TRC named BEM-TRC is used for milling NURBS curve swept surfaces using BEMs based on 3-axis CNC milling machines. In BEM-TRC, the TRC of a BEM involves radial and axial compensation. The cutting point (CP), which is the tangent point between a BEM and a NURBS curve, is considered as a calculation basis point. After obtaining a CP on a NURBS curve using the equi-arc length bisection interpolation method, the cutter center point of a BEM is calculated through off setting the CP the radius ( r ) distance of the BEM along its normal vector. Then the cutter location point of the BEM can be obtained according to the cutter center point. The CNC finishing program corresponding to the cutter location point can be obtained using Matlab software. The simulation based on VERICUT and machining based on a 3-axis milling machine verifies the effectiveness of the BEM-TRC. The over-cut phenomenon is avoided successfully when the BEM-TRC is used.

Research on optimization of milling performance of V-groove micro-texture ball-end milling cutter

Shucai Yang,Chaoyang Guo,Wei Ren 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.6

Titanium alloys generally have problems such as sticking, large cutting force, and poor heat dissipation during the cutting process., research shows that processing microtextures on the surface of the tool can effectively improve the above problems. Therefore, this paper designs the V-groove micro-textures based on the principle of bionics. Use simulation software to analyze the milling behavior of different V-groove micro-texture ball-end milling cutters for milling titanium alloys. Build a test platform to study the milling performance of the Vgroove micro-texture ball-end milling cutter for milling titanium alloys, obtain the prior choice range of V-groove micro-texture parameters, optimize the parameters based on the simulated annealing algorithm and conduct experimental verification. The results of the optimal tool parameters are that the opening angle of the V-groove micro-textures is 79°, the V-groove microtexture spacing is 170 μm, and the V-groove micro-texture width is 30 μm, the distance from blade of the V-groove micro-textures is 90 μm.

볼엔드밀 가공에서 미변형 칩두께의 이론적 해석

심기중,유종선,서남섭 전북대학교 공학연구원 ( 구 전북대학교 공업기술연구소 ) 2003 工學硏究 Vol.34 No.-

This paper presents a theoretical analysis to estimate the undeformed chip thickness required for cutting force simulation model development in ball-end milling. In machining, cutting force is estimated by multiplying cutting cross-section area to specific cutting forces. Specific cutting force, that is cutting parameter, is one of the important factors for cutting force prediction model and has different values according to workpiece materials. Cutting cross-section area is simply estimated in 2 dimensional cutting, but not simply estimated in 3 dimensional cutting due to complex cutting mechanics. In finishing cutting of free form surface using ball-end milling, cutting is almost performed in the ball part of the cutter and tool geometry such as tool radius, helix angle along length from tool tip are varied. As a result, cutting speed, effective helix angle and rake angle of the ball end mill are different according to length from tool tip. Study on undeformed chip thickness can be based other research, for example, cutting force prediction, tool deflection and dimensional error characteristics simulation. For undeformed chip thickness estimation, tool and chip geometry are analyzed and then the definition of chip thickness and estimation method are described. The results of analysis are compared with geometrical simulation and other method.

A combination method of the theory and experiment in determination of cutting force coefficients in ball-end mill processes

Kao, Yung-Chou,Nguyen, Nhu-Tung,Chen, Mau-Sheng,Huang, Shyh-Chour Society for Computational Design and Engineering 2015 Journal of computational design and engineering Vol.2 No.4

In this paper, the cutting force calculation of ball-end mill processing was modeled mathematically. All derivations of cutting forces were directly based on the tangential, radial, and axial cutting force components. In the developed mathematical model of cutting forces, the relationship of average cutting force and the feed per flute was characterized as a linear function. The cutting force coefficient model was formulated by a function of average cutting force and other parameters such as cutter geometry, cutting conditions, and so on. An experimental method was proposed based on the stable milling condition to estimate the cutting force coefficients for ball-end mill. This method could be applied for each pair of tool and workpiece. The developed cutting force model has been successfully verified experimentally with very promising results.