Prediction and modeling of roughness in ball end milling with tool-surface inclination

AbstractThis paper presents the application of Response Surface Methodology (RSM) coupled with Teaching Learning Based Optimization Technique (TLBO) for optimizing surface integrity of thin cantilever type Inconel 718 workpiece in ball end milling. The machining and tool related parameters like spindle speed, milling feed, axial depth of cut and tool path orientation are optimized with considerations of multiple response like deflection, surface roughness, and micro hardness of plate. Mathematical relationship between process parameters and deflection, surface roughness and microhardness are found out by using response surface methodology. It is observed that after optimizing the process that at the spindle speed of 2,000 rpm, feed 0.05 mm/tooth/rev, plate thickness of 5.5 mm and 15° workpiece inclination with horizontal tool path gives favorable surface integrity.

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Mechanistic Modeling of the Ball End Milling Process for Multi-Axis Machining of Free-Form Surfaces

Journal of Manufacturing Science and Engineering ◽

10.1115/1.1369357 ◽

2000 ◽

Vol 123 (3) ◽

pp. 369-379 ◽

Cited By ~ 85

Author(s):

Rixin Zhu ◽

Shiv G. Kapoor ◽

Richard E. DeVor

Keyword(s):

End Milling ◽

Chip Thickness ◽

Mechanistic Modeling ◽

Free Form ◽

Surface Geometry ◽

Workpiece Surface ◽

Ball End Milling ◽

Modeling Approach ◽

Free Form Surfaces ◽

Cutting Point

A mechanistic modeling approach to predicting cutting forces is developed for multi-axis ball end milling of free-form surfaces. The workpiece surface is represented by discretized point vectors. The modeling approach employs the cutting edge profile in either analytical or measured form. The engaged cut geometry is determined by classification of the elemental cutting point positions with respect to the workpiece surface. The chip load model determines the undeformed chip thickness distribution along the cutting edges with consideration of various process faults. Given a 5-axis tool path in a cutter location file, shape driving profiles are generated and piecewise ruled surfaces are used to construct the tool swept envelope. The tool swept envelope is then used to update the workpiece surface geometry employing the Z-map method. A series of 3-axis and 5-axis surface machining tests on Ti6A14V were conducted to validate the model. The model shows good computational efficiency, and the force predictions are found in good agreement with the measured data.

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Geometrical Modeling of Tool-Workpiece Contact Zone and Chip Formation in Finish Ball End Milling Process with Tool Inclination Angles

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.788 ◽

2016 ◽

Vol 693 ◽

pp. 788-794

Author(s):

Xiao Xiao Chen ◽

Jun Zhao

Keyword(s):

Contact Zone ◽

Measurement Method ◽

End Milling ◽

Milling Process ◽

Ball End Milling ◽

Geometrical Modeling ◽

Section Area ◽

Inclination Angles ◽

Area And Perimeter ◽

End Milling Process

The tool-workpiece contact zone is an important issue in the ball end milling process. This paper investigated the effects of tool inclination angles on the tool-workpiece contact zone, and variations of the cutting section area and perimeter with the increasing tilt and lead angles were also analyzed by geometrical modeling and measurement method for ball end milling process. The appropriate tool inclination angles, which could avoid the extrusion and friction between tool tip and the uncut materials, shorten the loading time on the cutting flute, and decrease the maximum cutting forces, could be preferentially selected according to the distribution characteristics of the tool-workpiece contact zone and the variations of the cutting section area and perimeter corresponding to various tool postures.

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