• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1643-1648
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• 2010

It is very difficult to polish non-magnetic materials by the magnetic abrasive polishing (MAP) process because magnetic force is required for MAP, but the magnetic force for non.magnetic materials is low. In this study, we aimed to develop a magnetic array table and control the magnetic polarity such that the magnetic force can be increased for the MAP of non-magnetic materials. The newly designed magnetic array table has 32 electro magnets, and the magnetic polarity of each electro-magnet can be easily controlled by changing the electric polarity. It was analytically verified that the magnetic flux density of non-magnetic materials can be varied by varying the applied magnetic polarity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.197-198
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• 2007

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.3
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• pp.313-318
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• 2013

Magnetic abrasive polishing is an advanced deburring process for nonmagnetic materials and micropattern products that have non-machinability characteristics. Despite these advantages, there are some problems with using MAP for deburring. MAP has introduced geometric errors into microgrooves because of an over-cutting force caused by uncontrolled magnetic abrasives in the MAP tool. Thus, in this study, to solve this problem, an EP (electrolyte polishing)-MAP hybrid polishing process was developed for deburring microgrooves in an STS316 material. In addition, an evaluation of EP-MAP for the deburring of microgrooves was carried out by profiling the burrs. The results of the experiment showed geometric errors after the deburring process using MAP. However, in the case of EP-MAP, no geometric error was observed after the process because of the lower material removal rate in EP-MAP.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.9
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• pp.1013-1018
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• 2014

Magnetic Abrasive Polishing (MAP) process is a nontraditional method for polishing the surface of workpiece by using the flexibility of tool. At present, a mixture of polishing abrasives and ferrous particles is used as the tool in the MAP process. Previously, an experiment was conducted with different sizes of polishing abrasives with an aim to improve the polishing accuracy. However, the sizes of ferrous particles are also expected to have a dominant effect on the process, warranting a study on the effect of the size of ferrous iron particles. In this study, an experiment was conducted using three different sizes of ferrous particles. Iron powder of average diameters 8, 78 and $250{\mu}m$ was used as ferrous particles. The effect of each ferrous particle size was evaluated by comparing the improvements in surface roughness. The particle size of a ferrous iron was found to play a significant role in MAP and particles of $78{\mu}m$ facilitated the best improvement in surface roughness.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.9
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• pp.923-928
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• 2015

In this paper, we propose an ultrasonic magnetic abrasive polishing (US-MAP) technique to effectively machine a high-strength material, and we prove the efficiency of hybrid finishing. We use Taguchi's experimental method to determine the influence of each parameter. Based on the results, US-MAP exhibited a higher polishing efficiency than traditional MAP, and a suitable frequency for hybrid finishing was 28 kHz. When investigating the effect of the parameters on the surface roughness, the ultrasonic amplitude had the greatest effect. However, when machining with $55-{\mu}m$ amplitude, the machining efficiency decreased as the magnetic flux density varied.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.319-320
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• 2008

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.2
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• pp.174-179
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• 2011

This paper focuses on the optimal step-over value for magnetic tool path. Since magnetic flux density is changed according to distance from center of magnetic tool. Enhanced surface roughness is also different according to change of radius. Therefore, to get a identical surface roughness on workpiece, it is necessary to find optimal tool path including step-over. In this study, response surface models for surface roughness according to change of radiuses were developed, and then optimal enhanced surface roughness for each radius was selected using genetic algorithm and simulated annealing to investigate relation between radius and surface roughness. As a result, it found that step-over value of 6.6mm is suitable for MAP of magnesium alloy.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.3
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• pp.319-324
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• 2013

In this study, an EP (electro-polishing)-MAP (magnetic abrasive polishing) hybrid process was developed as a precision finishing process. To evaluate the characteristics of this EP-MAP hybrid process, a series of experiments were carried out using various working gaps, current densities, and electrolyte concentrations. As a result, $NaNO_3$ was found to be very suitable as the electrolyte of the hybrid process because there was no electrochemical reaction with the CNT-Co composite. Moreover, an increase in the magnetic flux density affected the liquidity of the electrolyte and prevented it from flowing into the CNT-Co composite powder. For that reason, the lower liquidity of the electrolyte increased the thermal energy on the surface of the workpiece.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.387-388
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.141-142
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• 2010