Research on the Grinding Mechanism Based on the Cutting Simulation

2012 ◽  
Vol 510 ◽  
pp. 395-400
Author(s):  
Hong Xia Zhang ◽  
Wu Yi Chen

Grinding of metals is a complex material removal operation. Research on cutting process of a single abrasive grain is the basis of further understanding of grinding mechanism. In this investigation, the simulation and analysis for the non-uniform thermo-mechanical coupling intense stress fields in cutting zones of a single abrasive with negative rake are conducted by means of the FEM techniques. The cutting forces, the cutting temperature distribution and the strain rate in cutting zone are numerically demonstrated. Grinding mechanics are analyzed from microscopic view according to the simulation results. Research results facilitate a better understanding on the mechanics of grinding.

Author(s):  
Linwen Li ◽  
Bin Li ◽  
Xiaochun Li ◽  
Kornel F. Ehmann

Temperature-distribution measurements in cutting tools during the machining process are extremely difficult and remain an unresolved problem. In this paper, cutting temperature distributions are measured by thin film thermocouples (TFTCs) embedded into Polycrystalline Cubic Boron Nitride (PCBN) cutting inserts in the immediate vicinity of the tool-chip interface. Using these measurements, steady and dynamic phenomena during hard turning as well as the chip morphology and formation process were analyzed based on the cutting temperature distributions in the insert. The relationship between the cutting temperature-field distributions in the PCBN insert and the segmented chip formation is analyzed using temperature-distribution mapping. It is shown that the temperature-distribution in the cutting zone depends on the shearing band distribution in the chip and the thermal transfer rate from the heat generation zone to the cutting tool. Furthermore, it became evident that the material flow stress and the shearing bands greatly affect not only the chip formation morphology but also the cutting temperature field distributions in the cutting zone of the cutting insert.


2014 ◽  
Vol 1027 ◽  
pp. 340-343
Author(s):  
Geng Zhi ◽  
Wei Yao Bi ◽  
Jia Jun Tang ◽  
Xue Kun Li ◽  
Yi Ming Rong

Given that the grain geometry has an important impact on grinding process, it’s necessary to investigate the influence of grain shapes on grinding mechanism. In this paper, a 3D FEM model is developed to study the effects of CBN grain geometry on its microcutting performance under various speed levels, which is effective to understand the microcutting process qualitatively and quantitatively. The simulation results indicate that the single grain microcutting force ratio and material removal ratio are both sensitive to the grain shape and those grains with truncated tetrahedron shape of large cross-sectional area and negative rake angle would improve the cutting performance.


2007 ◽  
Vol 329 ◽  
pp. 681-686 ◽  
Author(s):  
Toshiyuki Obikawa ◽  
Ali Basti ◽  
Jun Shinozuka

The finite difference method was applied to simulate temperature distribution in the workpiece, cutting zone and tool in the orthogonal cutting process with multilayer coated sintered alumina tools. The analysis was conducted under different cutting speeds, while experiments were carried out to measure temperatures in different positions of the tool rake face using tools with built-in thin film thermocouples developed by the authors. The temperature distribution calculated along the rake face was consistent with experimental data. This proved that the finite difference modeling developed can be applied to the prediction of cutting temperatures of aluminum alloys for a range of ultra high cutting speeds.


2009 ◽  
Vol 416 ◽  
pp. 210-215 ◽  
Author(s):  
Wan Shan Wang ◽  
Chong Su ◽  
Zi Rui Pang ◽  
Jun Ming Hou

Three-dimensional cutting process of single grain in the shape of polygonal pyramid was simulated by coupled Euler-Lagrange method. The method makes the workpiece material free from its meshes. The material allowance can be removed without mesh separation criterion. The simulation results show that workpiece material flows to the side and front owing to the pressing of cutting plane. Chip flows out along the front of the grain upward. The deformation of workpiece material contacted with grain edge is very severe. Therefore there is large machining stress concentration at the contact zone of grain edge. It results in biggish residual stress and cutting temperature at the side and bottom of the groove. The contact stress at edge angle of abrasive grain is biggest. Therefore grain wear is severe in the position


2010 ◽  
Vol 42 (1) ◽  
pp. 99-124 ◽  
Author(s):  
A.K. Shukla ◽  
A. Mondal ◽  
A. Upadhyaya

The present study compares the temperature distribution within cylindrical samples heated in microwave furnace with those achieved in radiatively-heated (conventional) furnace. Using a two-dimensional finite difference approach the thermal profiles were simulated for cylinders of varying radii (0.65, 6.5, and 65 cm) and physical properties. The influence of susceptor-assisted microwave heating was also modeled for the same. The simulation results reveal differences in the heating behavior of samples in microwaves. The efficacy of microwave heating depends on the sample size and its thermal conductivity.


2020 ◽  
Vol 6 (6) ◽  
pp. 29-37
Author(s):  
Md. Shahwaz Hussain ◽  
Sujata Pouranik

The space between rotor and stator plays a very important role in the design and performance of rotating machinery. The thickness of the gap can vary considerably depending on the size and operating conditions for the different types of rotating machines. Analysis the air velocity and temperature distribution over the air flow gap in stator and motor. Changing the design of rotor to develop turbulence in air flow gap. Compare the velocity and temperature distribution of proposed design with previous studies. The simulation results pinpoint also the periodic heat transfer pattern from the rotor surface and this provides useful information for the prediction of the temperature distribution inside the rotating electrical machine. The simulation results of case-1 show about 117°C temperature inside the rotor machine. Then increase the number of slot inside the rotor machine the total temperature of the rotor machine decreases up to 76°C. Due to low temperature total efficiency of the system increases. And also reduces the loss due to heat. The turbulence effect inside the rotor increase in third case. Due to turbulence effect the air cover large amount of area inside the rotor. So total temperature of the rotor casing decreases. In a system where volume is held constant, there is a direct relationship between Pressure and Temperature. For this case, when the pressure increases then the temperature also increases. When the pressure decreases, then the temperature decreases. So pressure in third case decrease upto1.26Pa and temperature 76 °C.


2021 ◽  
Author(s):  
Maël Jeulin ◽  
Olivier Cahuc ◽  
Philippe Darnis ◽  
Raynald Laheurte

Abstract Most of the cutting models developed in the literature attest only to the presence of cutting forces in the balance of mechanical actions resulting from cutting. However, several studies have highlighted the presence of cutting moments during machining, and particularly 3D cutting in milling. The objective of this paper is to characterise phenomena associated with cutting moments by performing experimental mechanistic modelling in 3D cutting. For this purpose, several modelling factors will be investigated, such as the 3D cutting reference frame, the undeformed chip section, the cutting parameters, the cutting zone, etc. The predictive model of this study proves to be relatively efficient for an experimental model and allows a global prediction of cutting moments in milling. Furthermore, beyond the aspect of stress fields in the workpiece caused by cutting moments, this paper gives perspectives from an energetic point of view for which the share of moments in the energy balance could be substantial for monobloc tools.


1999 ◽  
Author(s):  
Fuqian Yang ◽  
J. C. M. Li ◽  
Imin Kao

Abstract The deformation of the wire in the wiresaw slicing process was studied by considering directly the mechanical interaction between the wire and the ingot. The wire tension on the upstream is larger than on the downstream due to the friction force between the wire and the ingot. The tension difference across the cutting zone increases with friction and the span of the contact zone. The pressure in the contact zone increases from the entrance to the exit if the wire bending stiffness is ignored. The finite element results show that the wire bending stiffness plays an important role in the wire deformation. Higher wire bending stiffness (larger wire size) generates higher force acting onto the ingot for the same amount of wire deformation, which will leads to higher material removal rate and kerf loss. While larger wire span will reduce the force acting onto the ingot for a given ingot displacement in the direction perpendicular to the wire.


2020 ◽  
Vol 902 ◽  
pp. 97-102
Author(s):  
Tran Trong Quyet ◽  
Pham Tuan Nghia ◽  
Nguyen Thanh Toan ◽  
Tran Duc Trong ◽  
Luong Hong Sam ◽  
...  

This paper presents a prediction of cutting temperature in turning process, using a continuous cutting model of Johnson-Cook (J-C). An method to predict the temperature distribution in orthogonal cutting is based on the constituent model of various material and the mechanics of their cutting process. In this method, the average temperature at the primary shear zone (PSZ) and the secondary shear zone (SSZ) were determined for various materials, based on a constitutive model and a chip-formation model using measurements of cutting force and chip thicknes. The J-C model constants were taken from Hopkinson pressure bar tests. Cutting conditions, cutting forces and chip thickness were used to predict shear stress. Experimental cutting heat results with the same cutting parameters using the minimum lubrication method (MQL) were recorded through the Testo-871 thermal camera. The thermal distribution results between the two methods has a difference in value, as well as distribution. From the difference, we have analyzed some of the causes, finding the effect of the minimum quantity lubrication parameters on the difference.


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