• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.38-45
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• 1996

A new grinding wheel was developed for the high performance grinding of difficult-to-grinding materials. The grinding performance of the newly developed wheel including grinding forces, grinding ratio, and surface roughness of ground surface was evaluated through experiments. Experimental results show that the performance of the newly developed wheel is superior to the conventional alumina wheel and comparable to the Sol-gel wheel. An experimental investigation on the wear of alumina grinding wheel was also carried out. The experiments consist of the measurements of fracture strength of the abrasive grains, grinding force, and the area of wear flats of grinding wheels. Microscopic examination of abrasive grains was executed to observe the progress of wheel wear. The results indicate that the 32A grain, which has relatively lower fracture strength, wears out faster than 5SS and 5SG. The wheel wear occurs much faster in wet grinding than in dry grinding. It has also been found that the grinding forces increase logarithmically with increasing wear flats.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.1
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• pp.45-51
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• 2004

In this paper, the relationship between the mechanical properties of alumina abrasives and grinding performance was investigated. Micro vickers hardness and fracture strength of all abrasives used in this study were measured. The grinding experiments were earned out with alumina grinding wheels made by various kinds of alumina abrasives including 32A, WA, ART, ALOMAX, and RA. The performance of such grinding wheel for grinding SKD11 was evaluated by specific grinding energy, grinding-ratio, and surface roughness. The grinding wheels composed by the harder abrasives and the lower fracture strength abrasives showed better grinding performance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.118-123
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• 1995

A new grindignwheel was developed for the high performance gfinding of difficult-to-grind materials. Te grinding performance (such as grinding forces, grinding ratio, and surface roughness of ground surface) of the newly developed wheel was evaluated through experiments. Experimental results show that the performance of the newly developed wheel is superior to conventional alumina wheel and comparable to the S-G wheel.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.5 no.1
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• pp.51-57
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• 1996

Although the system for establishing grinding operation standards mainly depends on the simulation method, it is desirable to obtain highly reliable grinding data and to develop experimental technology, And, it also needs to modify the simulation models if the simulation results do not coincide with special situation due to the difference of grinding machine, wheels and workpiece materials. If simple tests are carried out to evaluate these specificity, the reliability and utility of the system can be raised higher. Therefore, it is required for evaluating wheel ability and confirming the validity of the experimental methods as well as the possibility of exchanging the experimental data between Korea and Japan to preform several kinds of grinding experiments. In this paper, experiments of cylindrical plunge grinding were conducted using the wheels of the same specification made by three typical grinding wheel manufacturers both in Korea and Japan, respectively. The grinding power consumption grinding force, the ground surface roughness, and wheel wear were measured under the same dressing the grinding conditions. The average value and standard deviation of the experiment results were calculated to compared the grinding performance of the wheels made in both countries. The experiment results show that the grinding wheel performance of Korea's is nearly equal to that of Japan's for general purpose of grinding operation. In conclusion, it is possible to exchange the experimental data between Korea and japan.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.52-58
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• 1996

This paper described on the effect of residual stocks in internal grinding of tungsten carbide materials in order to improve the grinding efficiency as well as grinding accuracy. Through the fundamental investigation is carried out for tungsten carbide materials using electroplated diamond wheel, the residual stock after grinding process is effective to the grinding efficiency. The obtained results are as follows: (1) Under the depth of cut(t) is constant and decreasing the workpiece velocity(Vw), the residual stock after grinding is increased, but the difference is little less than the difference by table speed. (2) Increasing the wheel velocity, the residual stock after grinding is decreased. Therefore in order to minimize the residual stock, the wheel velocity should be increased as far as possible. (3) The surface roughness and out-of roundness increased with depth of cut and table speed, and decreased with wheel velocity, but it may as well adopt as much as possible under the dimensional tolerance which is required for high efficiency grinding. (4) In order to remove residual stock, the spark-out grinding shoule be done, and it also can be improved about 20~25% throughout spark-out grinding, and the number of optimal spark-out times were within 10 times.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4726-4731
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• 2011

This paper proposed the algorithm to select optimal grinding condition for plunge grinding in the batch production unit. In order to apply to the proposed algorithm, the state variable for plunge grinding process was defined and the optimal grinding condition for each cycle in batch production was decided by genetic algorithm. Based on the optimized grinding condition in each cycle, the optimal grinding condition for whole batch production was selected by dynamic programming. The proposed algorithm was evaluated by computer simulation.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.8
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• pp.52-59
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• 1996

Conventionally, grinding of stainless steel, aluminium ally, copper alloy, and titanum alloy are difficult to obtain the high quality finish, because they have the mechanical properties such as low hardness, high toughness which result in the loading of wheel and the poor surface finish. Inorder to perform the grinding operations for these sorts of materials easily, the discontinuous grinding wheel with multi-porous grooves has newly been developed. The multi-porous grooves were formed during wheel production. This discontinous grinding wheel increases the grinding performance. It is desirable to use the discontinuous grinding wheel when grinding materials wiht high efficiency and accuracy which is impossible by conventional wheels. In this paper, the constructing and manufacturing method of grinding wheel with multi-proous grooves are explained, and the grinding charateristics of discontinuous grinding wheel are also illustrate.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.10a
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• pp.219-224
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• 1997

In surface grinding, the contact between the grinding wheel and the workpiece introduces heat and resistance, which restrict the self-dressing of the grits and result in burrs and cracks on the workpiece. Therefore, before or during th grinding wheel for more accurate performance. In order to determine the dressing time monitoring method of grinding wheel in surface grinding, a three-dimensional computer simulation of the grinding operation has been attempted based on the contact mechanism and surface-shaping system between the grinding wheel and the workpiece. The optimal dressing time is determined based on the amount of the grain wear and work surface roughness.

• Journal of Mechanical Science and Technology
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• v.16 no.9
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• pp.1072-1077
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• 2002

A degree of sharpness in wheel grains affects the surface roughness and dimensional accuracy in the grinding process. If a wheel with dull grains is used, the grinding force is increased and the surface roughness is deteriorated. In ovder to produce a precision component economically, the magnitude of the wear amount in the grinding wheel has to be limited. In this study, experimental evaluation of a wheel life varying with the grinding ratio and static grinding force was conducted. The grinding ratio and grinding force were measured to seek the grinding performance of the WA wheel. The relationship between the grinding ratio and static grinding force was presented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.232-236
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• 1996

This paper deals with an on-the-machine measurement method for roughness of ground surface by using flux ratio of scattered lights. A sensor and control unit is developed so as to e applied to surface grinding processes. The performance of the sensor is compared with that of stylus. The experimental investigation shows that not onlythe sensor has good performance as a surface roughness sensor but alsothe sensor is very useful for monitoring grinding condition in order to detect ill-conditioned grinding or dressing time.