Three-dimensional transient cutting tool temperature field model based on periodic heat transfer for high-speed milling of compacted graphite iron

Cutting tool wear of polycrystalline cubic boron nitride (PcBN) tools was investigated in oblique turning experiments when machining compacted graphite iron at high cutting speeds, with the intention of elucidating the failure mechanisms of the cutting tools and presenting an analysis of the chip formation process. Dry finish turning experiments were conducted in a CNC lathe at cutting speeds in the range of 500–800m/min, at a feed rate of 0.05mm/rev and depth of cut of 0.2mm. Two different tool end-of-life criteria were used: a maximum flank wear scar size of 0.3mm (flank wear failure criterion) or loss of cutting edge due to rapid crater wear to a point where the cutting tool cannot machine with an acceptable surface finish (surface finish criterion). At high cutting speeds, the cutting tools failed prior to reaching the flank wear failure criterion due to rapid crater wear on the rake face of the cutting tools. Chip analysis, using SEM, revealed shear localized chips, with adiabatic shear bands produced in the primary and secondary shear zones.

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Discrete Element Simulation of the Stress Wave in High Speed Milling

Volume 1: Processes ◽

10.1115/msec2017-2906 ◽

2017 ◽

Cited By ~ 1

Author(s):

Yifei Jiang ◽

Jun Zhang ◽

Yong He ◽

Hongguang Liu ◽

Afaque Rafique Memon ◽

...

Keyword(s):

High Speed ◽

Cutting Tool ◽

Cutting Speed ◽

Discrete Element ◽

Rake Angle ◽

Stress Waves ◽

High Speed Milling ◽

Element Simulation ◽

Chip Size ◽

Distribution Of Stress

As cutting tool penetrates into workpiece, stress waves is induced and propagates in the workpiece. This paper aims to propose a two-dimensional discrete element method to analyze the stress waves effects during high speed milling. The dependence of the stress waves propagation characteristics on rake angle and cutting speed was studied. The simulation results show that the energy distribution of stress waves is more concentrated near the tool tip as the rake angle or the cutting speed increases. In addition, the density of initial cracks in the workpiece near the cutting tool increases when the cutting speed is higher. The high speed milling experiments indicate that the chip size decreases as the cutting speed increases, which is just qualitatively consistent with the simulation.

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Three-dimensional temperature field model of thermally decomposing resin composite irradiated by laser

High Power Laser and Particle Beams ◽

10.3788/hplpb20112303.0642 ◽

2011 ◽

Vol 23 (3) ◽

pp. 642-646

Author(s):

陈敏孙 Chen Minsun ◽

江厚满 Jiang Houman ◽

刘泽金 Liu Zejin

Keyword(s):

Temperature Field ◽

Field Model ◽

Resin Composite ◽

Three Dimensional ◽

Temperature Field Model

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Stability analysis for a single-point cutting tool deflection in turning operation

Advances in Mechanical Engineering ◽

10.1177/1687814019853188 ◽

2019 ◽

Vol 11 (6) ◽

pp. 168781401985318

Author(s):

Amon Gasagara ◽

Wuyin Jin ◽

Angelique Uwimbabazi

Keyword(s):

Cutting Forces ◽

High Speed ◽

Cutting Tool ◽

Single Point ◽

Three Dimensional ◽

High Speed Steel ◽

Cutting Parameters ◽

Depth Of Cut ◽

Beam Model ◽

Tool Deflection

In this article, a new model of regenerative vibrations due to the deflection of the cutting tool in turning is proposed. The previous study reported chatter as a result of cutting a wavy surface of the previous cut. The proposed model takes into account cutting forces as the main factor of tool deflection. A cantilever beam model is used to establish a numerical model of the tool deflection. Three-dimensional finite element method is used to estimate the tool permissible deflection under the action of the cutting load. To analyze the system dynamic behavior, 1-degree-of-freedom model is used. MATLAB is used to compute the system time series from the initial value using fourth-order Runge–Kutta numerical integration. A straight hard turning with minimal fluid application experiment is used to obtain cutting forces under stable and chatter conditions. A single-point cutting tool made from high-speed steel is used for cutting. Experiment results showed that for the cutting parameters above 0.1mm/rev feed and [Formula: see text]mm depth of cut, the system develops fluctuations and higher chatter vibration frequency. Dynamic model vibration results showed that the cutting tool deflection induces chatter vibrations which transit from periodic, quasi-periodic, and chaotic type.

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Analysis and Research of High Speed Milling of Thin-Walled Bracket Part Based on UG NX

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.129-131.256 ◽

2010 ◽

Vol 129-131 ◽

pp. 256-260

Author(s):

Yi Shu Hao ◽

Chuang Hai ◽

Xin Xing Zhu

Keyword(s):

High Speed ◽

Three Dimensional ◽

Structural Features ◽

Milling Process ◽

Analysis Method ◽

Three Dimensional Model ◽

Machining Processes ◽

Element Analysis ◽

High Speed Milling ◽

Tool Paths

Treating high speed milling theory as the guidance, this paper researched high speed milling process of bracket part based on UG NX. Combined with the structural features of bracket part, three dimensional model is built by UG NX CAD and machining processes are worked out after analysis. UG CAM module was applied to fabricate tool paths. At last, finite element analysis method is introduced to study the processing deformation by UG NX NASTRAN module, based on which measures to restrain processing deformations is advanced and processing sequences are optimized.

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Darryl E. Metzger Memorial Session Paper: Comparison of Calculated and Measured Heat Transfer Coefficients for Transonic and Supersonic Boundary-Layer Flows

Journal of Turbomachinery ◽

10.1115/1.2835653 ◽

1995 ◽

Vol 117 (2) ◽

pp. 248-254 ◽

Cited By ~ 1

Author(s):

C. Hu¨rst ◽

A. Schulz ◽

S. Wittig

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Reynolds Number ◽

High Speed ◽

Three Dimensional ◽

Supersonic Boundary Layer ◽

Nozzle Wall ◽

Transfer Coefficients ◽

Heat Transfer Coefficients ◽

Three Dimensional Finite Element

The present study compares measured and computed heat transfer coefficients for high-speed boundary layer nozzle flows under engine Reynolds number conditions (U∞=230 ÷ 880 m/s, Re* = 0.37 ÷ 1.07 × 106). Experimental data have been obtained by heat transfer measurements in a two-dimensional, nonsymmetric, convergent–divergent nozzle. The nozzle wall is convectively cooled using water passages. The coolant heat transfer data and nozzle surface temperatures are used as boundary conditions for a three-dimensional finite-element code, which is employed to calculate the temperature distribution inside the nozzle wall. Heat transfer coefficients along the hot gas nozzle wall are derived from the temperature gradients normal to the surface. The results are compared with numerical heat transfer predictions using the low-Reynolds-number k–ε turbulence model by Lam and Bremhorst. Influence of compressibility in the transport equations for the turbulence properties is taken into account by using the local averaged density. The results confirm that this simplification leads to good results for transonic and low supersonic flows.

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