IMPACT OF DEPTH OF CUT ON CHIP FORMATION IN AZ91HP MAGNESIUM ALLOY MILLING WITH TOOLS OF VARYING CUTTING EDGE GEOMETRY

Abstract Part-2 of this paper is focused on modeling the acoustic emission (AE) energy rate as a function of the specific cortical bone microstructures (viz., osteon, interstitial matrix, lamellar bone, and woven bone) and the depth-of-cut encountered by the bone sawtooth. First, the AE signal characteristics from the sawing experiments (in Part-1) are related to the pure haversian and pure plexiform regions of the cut. Using the cutting force predictions from Part-1 as input, the AE energy rate is then modeled in terms of the energies dissipated in the shearing and ploughing zones encountered by the rounded cutting edge. For this calculation, the rounded edge geometry of the sawtooth is modeled as a combination of (i) shear-based cutting from a negative rake cutting tool; and (ii) ploughing deformation from a round-nose indenter. The spread seen in the AE energy rate is captured by modeling the variations in sawed surface height profile, tool cutting edge geometry, and porosity of the bone. The model calibration and validation protocols are similar to those used in Part-1. The validated AE model is useful for process planning both in terms of its ability to predict AE energy rate trends and cutting force variations, based on the differences in the underlying bone microstructures.

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Investigations on chip formation of turned novel AM alloy

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408920961196 ◽

2020 ◽

pp. 095440892096119

Author(s):

Sunil Dutta ◽

Suresh Kumar Reddy Narala

Keyword(s):

Chip Formation ◽

Cutting Speed ◽

Chip Thickness ◽

Depth Of Cut ◽

Feed Speed ◽

Nose Radius ◽

Chip Shape ◽

High Feed ◽

Cutting Operation ◽

On Chip

Manufacturers across varied segments look for materials having appreciable machinability and surface integrities. Machinability of Mg alloys is a vital aspect during their acceptance for different applications. The chip shape generated in the cutting operation is a crucial attribute dominating the surface roughness, besides the dimension’s precision and the tool lifespan. The study discusses the chip-formation through the dry turning of a novel AM alloy (Mg alloy with 7 wt%Al-0.9 wt%Mn) using carbide insert with a 0.4 mm nose radius. During the experiments, three chip dimensions, namely chip-thickness, chip-length, and chip-width were measured. The turning variables, namely cutting speed( v), depth of cut (DOC), and feed ( f) is altered and applied to the workpiece. The chip shape was mostly dependent on the grouping of turning parameters. It was seen that favorable continuous chip formed at high feed and low DOC. The % contribution of each turning parameter on the chip shape was calculated. The experimental results are validated with the help of analysis of variance (ANOVA). The results show that the % contribution of feed, speed, and DOC on chip-thickness is 58.49%, 28.91%, and 12.49%; the contribution on chip-length is 76.89%, 20.81%, and 2.23%; and on chip-width, it is 25.28%, 0.48%, and 74.33%, respectively. Further, the chip shapes were compared with the shapes that were predicted by FEM software. The study offers vital insights for parameter selection to improve chip shape, which, in turn, contributes to higher surface quality.

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Modifications of the Cutting Edge Geometry and Chip Formation in Milling

CIRP Annals ◽

10.1016/s0007-8506(07)62165-9 ◽

1994 ◽

Vol 43 (1) ◽

pp. 63-68 ◽

Cited By ~ 14

Author(s):

R. Wertheim ◽

A. Satran ◽

A. Ber

Keyword(s):

Chip Formation ◽

Cutting Edge ◽

Edge Geometry

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Effect of Cutting Edge Geometry on Chip Flow Direction – Analytical Modelling and Experimental Validation

Procedia CIRP ◽

10.1016/j.procir.2017.03.327 ◽

2017 ◽

Vol 58 ◽

pp. 353-357 ◽

Cited By ~ 9

Author(s):

A. D’Acunto ◽

Gael Le Coz ◽

Abdelhadi Moufki ◽

D. Dudzinski

Keyword(s):

Experimental Validation ◽

Flow Direction ◽

Cutting Edge ◽

Analytical Modelling ◽

Edge Geometry ◽

Chip Flow ◽

On Chip

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Influence of the Cutting Edge Angle of a Titanium Instrument on Chip Formation in the Machining of Trabecular and Cortical Bone

The International Journal of Oral & Maxillofacial Implants ◽

10.11607/jomi.3499 ◽

2014 ◽

Vol 29 (4) ◽

pp. 942-948 ◽

Cited By ~ 1

Author(s):

Constantin See ◽

Marcus Stoetzer ◽

Martin Ruecker ◽

Max Wagner ◽

Paul Schumann ◽

...

Keyword(s):

Cortical Bone ◽

Chip Formation ◽

Cutting Edge ◽

Edge Angle ◽

On Chip

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Influence of Cutting Edge Radius in Micromachining AISI D2

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.393.253 ◽

2013 ◽

Vol 393 ◽

pp. 253-258 ◽

Cited By ~ 3

Author(s):

J.B. Saedon ◽

A. Hakim A. Halim ◽

H. Husain ◽

M.S. Meon ◽

Muhamad Fauzi Othman

Keyword(s):

Chip Formation ◽

Chip Thickness ◽

Cutting Edge ◽

Depth Of Cut ◽

Element Analysis ◽

Cutting Edge Radius ◽

Edge Radius ◽

Material Deformation ◽

Aisi D2 ◽

Aisi D2 Tool Steel

Chip formation is a dynamic process that is often non linear in nature. A chip may not form when the depth of cut is less than a minimum chip thickness. This paper presents an investigation of cutting edge radius effect on micromachining AISI D2 tool steel via simulation. The chip growth, chip formation and material deformation mechanism was investigated using commercial finite element analysis software. A model is developed with consideration of the arbitrary LagrangianEulerian (ALE) method. The chip growth, chip formation and material deformation was investigate under three criteria such as a/r<1, a/r>1 and a/r=1. The model showed that the chip is formed at a/r >1 while material extrusion performed under a/r<1.

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Influential Parameters in Determination of Chip Shape in High Speed Machining

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.496.211 ◽

2011 ◽

Vol 496 ◽

pp. 211-216

Author(s):

Tahsin Tecelli Öpöz ◽

Xun Chen

Keyword(s):

Fracture Energy ◽

Chip Formation ◽

Damage Evolution ◽

High Speed ◽

Rake Angle ◽

Depth Of Cut ◽

Chip Shape ◽

On Chip ◽

Cutting Processes

Cutting processes in machining involves the elastic and plastic formation where a layer of material is removed by a cutting tool to be removed from the workpiece in forms of various types of small chips. In this paper, a series of finite element simulations of 2D chip formation with various parameters are presented. Different types of chip shapes, such as continuous, discontinuous and serrated shape, are simulated under different conditions. A damage evolution technique based on fracture energy dissipation during material damage progression is used to demonstrate the influences on chip formation. It is concluded that the fracture energy in damage evolution is a crucial factor for the determination of chip shape. Further the influence of depth of cut and rake angle are considered in the simulations.

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Force and Stability Modeling for Non-Standard Edge Geometry Endmills

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4045057 ◽

2019 ◽

Vol 141 (12) ◽

Cited By ~ 5

Author(s):

Timothy No ◽

Michael Gomez ◽

Ryan Copenhaver ◽

Juan Uribe Perez ◽

Christopher Tyler ◽

...

Keyword(s):

Time Domain ◽

Cutting Edge ◽

Depth Of Cut ◽

Time Domain Simulation ◽

Edge Geometry ◽

Structured Light Scanning ◽

Spatial Coordinates ◽

The Time Domain ◽

Multiple Spindle ◽

Stability Modeling

Abstract This paper describes a reverse engineering solution for modeling the behavior of non-standard edge geometry endmills. Structured light scanning is used to produce a solid model of the endmill and spatial coordinates for the points that define the cutting edges that are extracted. These points are then used to determine the cutting edge radius and angle at equally spaced points along the tool's axis. This cutting edge geometry is applied directly in a time domain simulation that predicts the cutting force and tool/workpiece deflection for user-selected operating parameters. A good agreement between predicted and measured cutting forces is first demonstrated for two non-standard edge geometry endmills. Second, the results of stability tests are compared with simulation predictions for multiple spindle speed-axial depth of cut combinations using one of the endmills. The time records are analyzed by periodically sampling the measured and predicted displacement and velocity. Third, the time domain simulation is used to generate a stability map that separately identifies stable (forced vibration) behavior, secondary Hopf bifurcations, and period-n bifurcations.

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