Fundamental Study on the Precision Abrasive Machining Using a Cavitation in Reversing Suction Flow

2008 ◽  
Vol 389-390 ◽  
pp. 223-228
Author(s):  
Kazuhito Ohashi ◽  
Rong Jun Wang ◽  
Hiroyuki Hasegawa ◽  
Shinya Tsukamoto
Keyword(s):  
Surface Finish ◽  
Rapid Decrease ◽  
Abrasive Machining ◽  
Precision Manufacturing ◽  
Fundamental Study ◽  
Workpiece Surface ◽  
Abrasive Grains ◽  
Fine Surface ◽  
Stock Removal ◽  
Suction Flow

The purpose of this study is to make clear the machining effect of the precision abrasive machining using the cavitation in reversing suction flow, which can easily finish to a fine surface by a simple apparatus. The machining fluid including loose micro abrasive grains is sucked by a pump, and the cavitation occurs ahead of the nozzle fixed in the suction chamber because of the rapid decrease of pressure of machining fluid. We use the cavitation impact to make the abrasive grains to interfere with the workpiece surface. In this report, the possibility of application of the new abrasive machining to the precision manufacturing is investigated by analyzing the behavior of machining fluid, the stock removal and the surface finish in machining of glass. The cavitation impact is strongest under the nozzle clearance of 20mm and restriction nozzle diameter of 4mm. Glass surface is finished up to several nanometers in Ry with slight stock removal by the proposed abrasive machining.

Application of Cavitation Aided Abrasive Machining to Manufacture of Micro Air Vents on Injection Molds

2012 ◽  
Vol 565 ◽  
pp. 597-602
Author(s):  
N. Lu ◽  
K. Ohashi ◽  
A. Hirashima ◽  
A. Shimizu ◽  
S. Tsukamoto
Keyword(s):  
Surface Finish ◽  
Abrasive Machining ◽  
Precision Manufacturing ◽  
Practical Application ◽  
Workpiece Surface ◽  
Abrasive Grains ◽  
Fine Surface ◽  
Rapid Decompression ◽  
Suction Flow ◽  
Machining Characteristics

The purpose of this study is a practical application of the cavitation aided abrasive machining (CAAM). This study shows the machining effect of the precision abrasive machining on injection molds using the cavitation in a suction flow of slurry, which can easily finish to a fine surface by a simple apparatus. The cavitation occurred above the workpiece surface downstream of the restrictor tip because of the rapid decompression and then the abrasive grains in the water interfere with the workpiece surface by the cavitation impact. In this report, the possibility of application of the cavitation aided abrasive machining to the precision manufacturing of micro air vents on the rib of injection molds are generated by using masks of a certain thickness that are made on a special masking equipment, and the machining characteristics of micro air vents are investigated by analyzing the depth of micro grooves and the surface finish in machining of injection molds. When the depth of the micro grooves is approximately 1μm in the machining of 30 minutes, the manufacture of molding parts without burrs or residual voids is carried out by CAAM.

Study on Cavitation Aided Abrasive Machining on Glass

2009 ◽  
Vol 407-408 ◽  
pp. 654-657
Author(s):  
Kazuhito Ohashi ◽  
Shinya Tsukamoto ◽  
Toshikatsu Nakajima
Keyword(s):  
Polished Glass ◽  
Abrasive Machining ◽  
Machined Surface ◽  
Workpiece Surface ◽  
Abrasive Grains ◽  
Fine Surface ◽  
Effective Use ◽  
Stock Removal ◽  
Suction Flow ◽  
Machining Characteristics

The purpose of this study is to develop the cavitation aided abrasive machining which makes effective use of cavitation occurring in suction flow of slurry for fine machining. In this paper, a fundamental machining phenomenon of glass using the cavitation suction flow is clarified and machining characteristics are experimentally investigated by the observation of machined surface and surface roughness, stock removal and cavitation impact. Abrasive grains impinge on a workpiece surface to physically remove work material and generate fine surface in the machining. Then it can finish the polished glass surface of 9.3nmRz down to about 5.0nmRz by using abrasives of WA 4000.

Analysis of Energy Partition in Grinding

1995 ◽  
Vol 117 (1) ◽  
pp. 55-61 ◽  
Author(s):  
C. Guo ◽  
S. Malkin
Keyword(s):  
Wheel Speed ◽  
Energy Partition ◽  
Composite Surface ◽  
Workpiece Surface ◽  
Abrasive Grains ◽  
Temperature Distributions ◽  
Analytical Results ◽  
Creep Feed Grinding ◽  
Grinding Fluid ◽  
Creep Feed

An analysis is presented for the fraction of the energy transported as heat to the workpiece during grinding. The abrasive grains and grinding fluid in the wheel pores are considered as a thermal composite which moves relative to the grinding zone at the wheel speed. The energy partition fraction to the workpiece is modeled by setting the temperature of the workpiece surface equal to that of the composite surface at every point along the grinding zone, which allows variation of the energy partition along the grinding zone. Analytical results indicate that the energy partition fraction to the workpiece is approximately constant along the grinding zone for regular down grinding, but varies greatly along the grinding zone for regular up grinding and both up and down creep-feed grinding. The resulting temperature distributions have important implications for selecting up versus down grinding especially for creep-feed operations.

scholarly journals Fine Surface Finish of a Hardened Stainless Steel Using a New Burnishing Tool

2017 ◽  
Vol 10 ◽  
pp. 208-217 ◽  
Author(s):  
Fang-Jung Shiou ◽  
Shih-Ju Huang ◽  
Albert J. Shih ◽  
Jiang Zhu ◽  
Masahiko Yoshino
Keyword(s):  
Stainless Steel ◽  
Surface Finish ◽  
Fine Surface

Grinding Process Size Effect and Kinematics Numerical Analysis

1999 ◽  
Vol 122 (1) ◽  
pp. 59-69 ◽  
Author(s):  
William L. Cooper ◽  
Adrienne S. Lavine
Keyword(s):  
Steady State ◽  
Removal Rate ◽  
Empirical Relationship ◽  
Three Dimensional ◽  
Depth Of Cut ◽  
Grinding Process ◽  
Zone Length ◽  
Abrasive Grains ◽  
Three Dimensional Modeling ◽  
Stock Removal

The present work developed numerical codes that simulate steady-state grinding process kinematics. The three-dimensional modeling procedure entails the following: specifying the sizes, shapes, and positions of individual abrasive grains on the wheel surface; geometrically calculating the abrasive grains’ depth of cut distributions along the grinding zone as they pass through the grinding zone (neglecting wheel, abrasive grain, and workpiece deflections); using an empirical relationship to relate the abrasive grains’ geometric depths of cut to the grains’ actual depths of cut; and updating the workpiece surface to account for material removal. The resulting data include the abrasive grains’ average depth of cut distribution along the grinding zone, stock removal depth, stock removal rate, grinding zone shape, grinding zone length, percentage of grains impacting the workpiece, grain-workpiece impact frequency, etc. The calculated grinding zone lengths compare favorably with experimental data. This article examines a number of steady-state grinding processes. [S1087-1357(00)00101-5]

Methodology for Evaluation of Treated Steels and Alloys in Abrasive Processing

2021 ◽  
Vol 410 ◽  
pp. 262-268
Author(s):  
Vyacheslav M. Shumyacher ◽  
Sergey A. Kryukov ◽  
Natal'ya V. Baidakova
Keyword(s):  
Physical And Mechanical Properties ◽  
Metals And Alloys ◽  
Grinding Wheel ◽  
Measuring Instruments ◽  
Abrasive Machining ◽  
Machining Performance ◽  
Abrasive Grains ◽  
Abrasive Tools ◽  
Composition Structure ◽  
Grinding Operations

One of the critical physical and mechanical properties of metals and alloys is the suitability for abrasive machining. Machining by abrasive tools is the final operation that sets the desired macro-geometry parameters of processed blanks and microgeometry parameters of processed surfaces such as roughness and length of a bearing surface. Abrasive machining determines the most important physical and mechanical parameters of a blank surface layer, i.e. stresses, phase composition, structure. Machinability by abrasive tools depends on the machining performance affected both by the blank material properties and various processing factors. In our previous studies, we proved that during abrasive machining the metal microvolume affected by abrasive grains accumulates energy. This energy is used for metal dispersion and is converted into heat. According to the theoretical studies described herein, one may note the absence of a reliable and scientifically valid method as well as measuring instruments to determine the machinability of metals and alloys by abrasive tools. For this reason, we suggested a method simulating the effect the multiple abrasive grains produce in a grinding wheel, and enabling us to identify machinability of metals and alloys, select the most efficient abrasive materials for machining of the same, and form the basis for development of effective grinding operations.

COMPARISON OF EXPERIMENTALLY MEASURED AND SIMULATED WORKPIECE AND GRINDING WHEEL TOPOGRAPHY USING A NEW DRESSING MODEL

2016 ◽  
Vol 40 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Abdalslam Darafon ◽  
Andrew Warkentin ◽  
Robert Bauer
Keyword(s):  
Surface Finish ◽  
Metal Removal ◽  
Ground Surface ◽  
Cutting Edge ◽  
Edge Density ◽  
Grinding Wheel ◽  
Workpiece Surface ◽  
Wheel Topography ◽  
Grinding Wheel Topography ◽  
Grinding Conditions

This paper presents a new empirical model of the dressing process in grinding which is then incorporated into a 3D metal removal computer simulator to numerically predict the ground surface of a workpiece as well as the dressed surface of the grinding wheel. The proposed model superimposes a ductile cutting dressing model with a grain fracture model to numerically generate the resulting grinding wheel topography and workpiece surface. Grinding experiments were carried out using “fine”, “medium” and “coarse” dressing conditions to validate both the predicted wheel topography as well as the workpiece surface finish. For the grinding conditions used in this research, it was observed that the proposed dressing model is able to accurately predict the resulting workpiece surface finish for all dressing conditions tested. Furthermore, similar trends were observed between the predicted and experimentally-measured grinding wheel topographies when plotting the cutting edge density, average cutting edge width and average cutting edge spacing as a function of depth for all dressing conditions tested.

Experimental Investigation for the Multi-objective Optimization of Machining Parameters on AISI D2 Steel Using Particle Swarm Optimization Coupled with Artificial Neural Network

2020 ◽  
Vol 19 (03) ◽  
pp. 589-606 ◽  
Author(s):  
Vipin Gopan ◽  
K. Leo Dev Wins ◽  
Gecil Evangeline ◽  
Arun Surendran
Keyword(s):  
Neural Network ◽  
Surface Roughness ◽  
Artificial Neural Network ◽  
Cutting Force ◽  
Surface Finish ◽  
Fitness Function ◽  
Machining Parameters ◽  
Swarm Optimization ◽  
Fine Surface ◽  
Aisi D2

High Carbon High Chromium (or AISI D2) Steels, owing to the fine surface finish they produce upon grinding, find lot of applications in die casting. Machining parameters affect the surface finish significantly during the grinding operation. In this context, this work puts an effort to arrive at the optimum machining parameters relating to fine surface finish with minimum cutting force. The material removal caused by the abrasive grinding wheel makes the process a very complex and nonlinear machining operation. In many situations, traditional optimization techniques fail to provide realistic optimum conditions because of the associated complexity. In order to overcome this issue, particle swarm optimization (PSO) coupled with artificial neural network (ANN) is applied in this research work for parameter optimization with the objective of achieving minimum surface roughness and cutting force. The machining parameters selected for the investigation were table speed, cross feed and depth of cut and the responses were surface roughness and cutting force. ANNs, inspired from biological neural networks, are well capable of providing patterns, which are too complex in behavior. The ANN model developed was used as the fitness function for PSO to complete the optimization. Optimization was also carried out using conventional response surface methodology-genetic algorithm (RSM-GA) approach in which regression equation developed with RSM was considered as the fitness function for GA. Confirmatory experiments were conducted and the comparison showed that PSO coupled with ANN is a reliable tool for complex optimization problems.

Analysis of finishing forces and surface finish during magnetorheological abrasive flow finishing of asymmetric workpieces

2019 ◽  
Vol 2 (2) ◽  
pp. 133-151 ◽  
Author(s):  
Jayant ◽  
V. K. Jain
Keyword(s):  
Magnetic Field ◽  
Surface Finish ◽  
Research Work ◽  
Workpiece Surface ◽  
Abrasive Particles ◽  
Wear And Tear ◽  
Frictional Forces ◽  
Spatially Varying ◽  
Final Surface Finish ◽  
Abrasive Flow Finishing

Magnetorheological abrasive flow finishing (MRAFF) is an advanced hybrid process for producing ultrafine finished surfaces. Such surfaces reduce frictional forces and thereby minimize wear and tear to increase functional lifetime of the components. In the present research work, a model has been developed for simulating the results of MRAFF process. First, magnetic field is simulated and then a detailed study on the rheology of the magnetorheological polishing (MRP) fluid is conducted to develop a viscosity model for the flow of non-Newtonian shear thinning fluid. To calculate the forces acting in the process of material removal, the flow of MRP fluid around an asymmetric workpiece (knee joint) in a spatially varying magnetic field is simulated. Finishing forces exerted by the abrasive particles on the workpiece surface are analysed to develop a model for predicting surface roughness. A methodology has been proposed to evolve a variable correction factor to determine active abrasive particles at different locations on the workpiece surface for accurate simulation of surface finish operation. It is found that the magnetic field greatly influences the process performance by governing the viscosity of the MRP fluid and the distribution of the abrasive particles in the medium. During finishing of an asymmetric workpiece, the surface finish obtained at different locations on the workpiece surface is different. The developed model is capable to predict final surface finish within the acceptable accuracy when compared with the experimental results.

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