• 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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• 1996.03a
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• pp.108-113
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• 1996

Conventionally, grinding of stainless steel, aluminium alloy, copper alloy, and titanum alloy is difficult due to the mechanical properties such as low hardness, high toughness which result in the loading of wheel and the poor surface finish. In order to grind this sort of materials easily, discontinuous grinding wheel with multi-porous grooves was newly developed. The multi-porous grooves were formed during wheel production. This discontinuous grinding wheel drastically increases the grinding performance. It is desirable to use the discontinuous grinding wheel when grinding materials with high efficiency and accuracy which is impossible by conventional wheels. In this paper, the construction and manufacturing method of grinding wheel with multi-porous grooves are explained. The grinding charateristics of discontinuous grinding wheel was also illustrated.

• 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.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.9
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• pp.2866-2874
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• 1996

In the grinding of difficult-to-materials, the major problmes of conventional grinding are grinding burn, wheel wear, grinding surface crack, loading and glazing, When a conventioanl grinding wheel is used, wheel wear and grinding surface crack easily occur in low heat conductive material and annealed steel. Intermittent grinding is suitable for diffcult-to-matrical such as stainless steel, titanium alloy, aluminum alloy and copper alloy. The purpose of this paper is to develop a new type intermittent wheel of the grinding system for improving the problem of stainless steel grinding, to observe the effect of intermittent grinding on surface quality and grinding characteristics of stainless steel grinding using intermittent grinding wheel. The characteristics of intermittent grinding system improve surface quality, low grinding temperature and low loading.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.7
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• pp.63-69
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• 2003

Through the previous works, it was found that the laminated grinding wheel is more efficient to generate smoother surface in short time than general grinding wheels. But, if the laminated grinding wheel is easily worn-out, it is impossible to apply this wheel in the real grinding process, because the periodic time for dressing is closely linked to the productivity of the process. So, it is required to investigate the wear of the laminated grinding wheel fer studying the periodic time for dressing. But it is difficult to analyze the dressing period quantitavely. Therefore, in this study, periodic times for dressing of the laminated grinding wheel and general grinding wheel are deduced from the relationship between the wear of grinding wheels and the surface roughness changes according to the number of traverse in cylindrical traverse grinding through experiments. This study shows that there are some differences in the wheel wear mechanisms between the general and laminated grinding wheels. As a result, it is also found that the periodic time for dressing of the laminated grinding wheel is longer than that of the general grinding wheel.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.101-108
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• 2002

In the grinding process, the degree of the sharpness in wheel gram affects the surface roughness and the dimensional accuracy. If a wheel with dull grains is used, the grinding force will be increased and the surface roughness deteriorated. To produce a precision component, the magnitude of parameters related to the wear amount of a grinding wheel has to be limited. In this study, a variation of the grinding force and the surface roughness were measured to seek the machining characteristics of the W A and CBN wheels. From the wear amount of the grinding wheel and the removal rate of workpiece, the grinding ratio was calculated. And also the wheel life was determined at a rapid decreasing point of the grinding ratio. The difference between the surface of wheel-workpiece before grinding and after wheel life was clearly verified with a microscopic photo.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.5
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• pp.165-171
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• 2000

To get smoother ground surface, it is required to replace the grinding wheel with a finer-grit wheel. When the operator replaces the grinding wheel, the balancing and dressing of the wheel surface are necessary. So this replacement has a lot of problems like inconvenience to operators, delays in the operation time, and ineffectiveness in the production process. Therefore, a laminated grinding wheel, which consists of three layers, is provided. The side layers are coarse grits and the middle layer is made up of fine grits. To show the effectiveness of the laminated grinding wheel, experiments on the surface roughness and the material removal rate were performed respectively. As a result, it was found that the grinding process using a laminated grinding wheel can generate smoother ground surface in shorter time.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.194-199
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• 1996

Grinding burn formed on the ground surface is related to the maximum temperature of workpiece surface and wheel temperature in the grinding process. The thermal characteristics of workpiece and grinding conditions on the surface temperature of the oxidation growing layer after get out of contact with the grinding wheel. The assumption used in grinding power signatures leads to the local temperature distribution between grinding wheel and workpiece, i.e., a single curve determines temperatures anywhere within the grinding wheel at anytime. This information is useful in the study of the grinding bum penetration into the wheel and thus provides an presentation of grinding trouble monitoring for the burning. On the basis of grinding power signatures in the wheel, thermally optimum conditions are defined and controlled. To cope with grinding burn, the use of grinding power signatures is an effective monitoring systems when occurring the grinding process. In this paper, the identified parameters suggested in this study which are derived from the grinding power signatures are presented.

• 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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• 2005.10a
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• pp.344-349
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• 2005

This paper presents a geometrical error analysis of wheel curve generation method for micro aspheric surface machining using parallel grinding method. In aspheric grinding, wheel wear in process is crucial parameter for profile error of the ground surface. To decrease wheel weal parallel grinding method is adopted. Wheel and work piece (Tungsten carbide) contact point changes during machining process. In truing process of the wheel radius is determined by the angle and distance between wheel and truer. Wheel radius error is predominantly affected by vertical deviation between the wheel rotation center and the truer center Simulation for vertical error and wheel radius error shows same tendency that expected by geometrical analysis. Experimental results show that the analysis of curve generation method matches with simulations and wheel radius errors.