<title>Effects of diamond cutting tool's rake angle and edge radius on the diamond turned surface quality</title>

The effect of the radial force applied by a ring debarker tip to frozen balsam fir (Abies balsamea (L.) Mill.) logs, obtained at three positions on the stem, was studied. A one-armed ring debarker prototype was built, which controlled the radial force, the rake angle, and cutting and feed speeds. Balsam fir logs at −19 °C were debarked at three levels of radial force. The rake angle, tip overlap, tip edge radius, and cutting and feed speeds were kept constant. Debarking quality was evaluated by two criteria: the proportion of bark remaining on log surfaces and the amount of wood fibres in bark residues. Log characteristics (dimensions, eccentricity, bark thickness, and knot features), bark–wood shear strength, and the basic densities of sapwood and bark were also measured. Results showed that the radial force had a significant effect on debarking quality. The proportion of bark remaining on log surfaces increased while the amount of wood fibres in bark residues decreased as radial force decreased. A radial force of 18.5 N·mm−1 is suggested for an optimal debarking quality. In contrast, log position on the stem did not affect the debarking quality indicators. Results also showed that the proportion of bark remaining on log surfaces increases as bark–wood shear strength and the proportion of knot surface increase, while the amount of wood fibres in bark residues increases as bark–wood shear strength decreases and logs are more eccentric. The results give useful information to improve the debarking process within the studied range of log diameters and debarking parameters.

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Edge Effect Analysis on orthogonal cutting the Plastic Metal Material-C10100 with Negative Rake Angle Tool

E3S Web of Conferences ◽

10.1051/e3sconf/202020602021 ◽

2020 ◽

Vol 206 ◽

pp. 02021

Author(s):

Yanchun Ding ◽

Guangfeng Shi

Keyword(s):

Edge Effect ◽

Orthogonal Cutting ◽

Rake Angle ◽

Contact Friction ◽

Cutting Condition ◽

Micro Cutting ◽

Metal Material ◽

Edge Radius ◽

Plastic Metal ◽

Tool Surface

With the rapid development of the precision grinding and micro-cutting technology, scholars have become more and more interested in the forming mechanism and related characteristics of the rounded-edge tool and the negative rake angle tool. Based on DEFORM-2D forming software, this paper investigates the edge effect of the negative rake angle tool in micro-cutting condition. Through the simulation comparison analysis, it is clear that three deformation regions appear in front of the tool surface, namely the first shear-slip region, the second tool-material contact friction region and the third edge effect deformation region when the negative rake tool cuts the plastic metal material-C10100 with a large edge radius. And a triangle stagnant region appears in front of the tool surface due to the edge effect. By analysing the influence of the ratio of the edge radius to the cutting thickness on the mechanism of orthogonal cutting of negative rake tools, it is found that the minimum cutting thickness value is between

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A New Model and Analysis of Orthogonal Machining With an Edge-Radiused Tool

Journal of Manufacturing Science and Engineering ◽

10.1115/1.1285886 ◽

1999 ◽

Vol 122 (3) ◽

pp. 384-390 ◽

Cited By ~ 59

Author(s):

Jairam Manjunathaiah ◽

William J. Endres

Keyword(s):

Shear Stress ◽

Deformation Zone ◽

Lower Boundary ◽

Chip Thickness ◽

Rake Angle ◽

Shear Angle ◽

Force Model ◽

Uncut Chip Thickness ◽

Edge Radius ◽

Machining Force

A new machining process model that explicitly includes the effects of the edge hone is presented. A force balance is conducted on the lower boundary of the deformation zone leading to a machining force model. The machining force components are an explicit function of the edge radius and shear angle. An increase in edge radius leads to not only increased ploughing forces but also an increase in the chip formation forces due to an average rake angle effect. Previous attempts at assessing the ploughing components as the force intercept at zero uncut chip thickness, which attribute to the ploughing mechanism all the changes in forces that occur with changes in edge radius, are seen to be erroneous in view of this model. Calculation of shear stress on the lower boundary of the deformation zone using the new machining force model indicates that the apparent size effect when cutting with edge radiused tools is due to deformation below the tool (ploughing) and a larger chip formation component due to a lower shear angle. Increases in specific energy and shear stress are also due to shear strain and strain rate increases. A consistent material behavior model that does not vary with process input conditions like uncut chip thickness, rake angle and edge radius can be developed based on the new model. [S1087-1357(00)01302-2]

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Scratching Experimental Research on Critical Cut Depth of Glass BK7

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.589-590.194 ◽

2013 ◽

Vol 589-590 ◽

pp. 194-197 ◽

Cited By ~ 1

Author(s):

Peng Jia

Keyword(s):

Surface Quality ◽

Optical Glass ◽

Dimensional Accuracy ◽

Cutting Fluid ◽

Dry Cutting ◽

Diamond Cutting ◽

Fluid Properties ◽

Indentation Experiment ◽

Cut Depth

For the technology of diamond cutting of optical glass, the machinability of glass is poor, which hindering the practical application of this technology. In order to investigate and ameliorate the machinability of glass, and achieve optical parts with the satisfied surface quality and dimensional accuracy, this paper first conducted SF6 indentation experiment by Vickers microhardness instrument, and then the scratching tests with increasing depths of cut were conducted on glass SF6 to evaluate the influence of the cutting fluid properties on the machinability of glass. Based on this, turning tests were carried out, and the surface quality of SF6 was assessed based on the detections of the machined surfaces roughness. Experimental results indicated that compared with the process of dry cutting, the machinability of glass SF6 can be improved by using the cutting fluid

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Multi-objective Optimization of Turning Tool Geometric Parameters Based on Kriging Model

Journal of Physics Conference Series ◽

10.1088/1742-6596/2137/1/012046 ◽

2021 ◽

Vol 2137 (1) ◽

pp. 012046

Author(s):

Jianxiang Sun ◽

Huan Xie ◽

Wei Zeng ◽

Yaoyao Tong ◽

Zhenyu Cai

Keyword(s):

Rake Angle ◽

Geometric Parameters ◽

Cutting Edge ◽

Cutting Performance ◽

Performance Parameters ◽

Multi Objective Optimization ◽

Cutting Edge Radius ◽

Multi Objective ◽

Edge Radius ◽

Relief Angle

Abstract Cutting performance parameters of turning tool in different geometric parameters are obtained using finite element model, and the Kriging models of cutting stress and temperature are constructed, taking the cutting performance parameters as training samples. The multi-objective optimization model of turning tool geometric parameters is established based on the constructed cutting performance Kriging models, in which the design variables are rake angle, relief angle and cutting-edge radius, the objective parameters are cutting stress and temperature. The multi-island genetic algorithm is used to obtain the optimum turning tool geometric parameters: rake angle γo is 10.59°, relief angle λs is 6.15°and cutting-edge radius γE is 0.73mm. The simulation results after optimization demonstrate that the corresponding cutting temperature reduces 263.1°C, cutting stress drops by 550.8MPa.

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Prediction of Surface Quality Based on the Non-Linear Vibrations in Orthogonal Cutting Process: Time Domain Modeling

Journal of Manufacturing and Materials Processing ◽

10.3390/jmmp3030053 ◽

2019 ◽

Vol 3 (3) ◽

pp. 53

Author(s):

Kibbou ◽

Dellagi ◽

Majdouline ◽

Moufki

Keyword(s):

Surface Quality ◽

Orthogonal Cutting ◽

Cutting Speed ◽

Chip Thickness ◽

Rake Angle ◽

Cutting Conditions ◽

Process Time ◽

Mean Deviation ◽

Non Linear ◽

Linear Vibrations

This work presents an analysis of relationships between the non-linear vibrations in machining and the machined surface quality from an analytical model based on a predictive machining theory. In order to examine the influences of tool oscillations, several non-linear mechanisms were considered. Additionally, to solve the non-linear problem, a new computational strategy was developed. The resolution algorithm significantly reduces the computational times and makes the iterative approach more stable. In the present approach, the coupling between the tool oscillations and (i) the regenerative effect due to the variation of the uncut chip thickness between two successive passes and/or when the tool leaves the work (i.e., the tool disengagement from the cut), (ii) the friction conditions at the tool–chip interface, and (iii) the tool rake angle was considered. A parametric study was presented. The correlation between the surface quality, the cutting speed, the tool rake angle, and the friction coefficient was analyzed. The results show that, during tool vibrations, the arithmetic mean deviation of the waviness profile is highly non-linear with respect to the cutting conditions, and the model can be useful for selecting optimal cutting conditions.

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Experimental Investigation of the Machinability of Single Crystal Silicon in Laser-Assisted Diamond Cutting

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2020-8251 ◽

2020 ◽

Author(s):

Jinyang Ke ◽

Xiao Chen ◽

Jianguo Zhang ◽

Changlin Liu ◽

Guoqing Xu ◽

...

Keyword(s):

Single Crystal ◽

Surface Quality ◽

Laser Power ◽

Single Crystal Silicon ◽

Depth Of Cut ◽

Maximum Height ◽

Critical Depth ◽

Diamond Cutting ◽

Crystal Silicon ◽

Critical Depth Of Cut

Abstract Laser-assisted diamond cutting is a promising process for machining hard and brittle materials. A deep knowledge of material removal mechanism and attainable surface integrity are crucial to the development of this new technique. This paper focuses on the application of laser-assisted diamond cutting to single crystal silicon to investigate key characteristics of this process. The influence of laser power on the ductile machinability of single crystal silicon, in terms of the critical depth of cut for ductile-brittle transition in laser-assisted diamond cutting, is investigated quantitatively using a plunge-cut method. The experimental results reveal that this process can enhance the silicon’s ductility and machinability. The critical depth of cut has been increased by up to 330% with laser assistance, and its degree generally increases with the increase of laser power. The cross-sectional transmission electron microscope observation results indicate that laser-assisted diamond cutting is able to realize the subsurface damage free processing of single crystal silicon. In order to verify the ability of the laser-assisted diamond cutting to improve the surface quality, the face turning tests are also carried out. A significant improvement of surface quality has been obtained by laser-assisted diamond cutting: Sz (maximum height) has been reduced by 85% and Sa (arithmetical mean height) has been reduced by 45%.

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