• 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 the Korean Society of Safety
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• v.7 no.4
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• pp.13-21
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• 1992

The purpose of this reserch is to suggest grinding temperature for high effect grinding and to clarify the sufficient grinding heat by experiment and theory(developed finite element program). Main results to be obtained are as follows : 1) The grinding temperature distribution by F. E. M is comparatively in good apreement with the experimental results. 2) The up cut grinding method of grinding methods is decreased burning effect. 3) Regardless of the table speed on the temperature distribution in grinding surface layer, cooling effect is about 6-8times when developed nozzle is used.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.9
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• pp.59-65
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• 2002

Grinding temperature between a grinding wheel and a workpiece surface, rising rapidly during a machining operation, has bad effects on a surface integrity such as the burning, the residual stress and the crack. In this study, the temperature distribution was obtained briefly by the finite element method and the grinding temperature of a workpiece varying with the grinding condition was measured experimentally. For obtaining the grinding temperature, a thermocouple method was applied. Three thermocouples were inserted in a surface of each workpiece. Changed grinding conditions were the depth of cuts, the feedrate, the dry and wet grinding, the up and down grinding and the number of pieces.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.65-70
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• 2000

Although the net-shape molding of composites is generally recommended, molded composites frequently requires cutting or grinding due to the dimensional inaccuracy for precision machine elements. During the composite machining operations such as cutting and grinding, the temperature at the grinding area may increase beyond the allowed limit due to the low thermal conductivity of composites, which might degrade the matrix of composite. Therefore, in this work, the temperature at the grinding point during surface grinding of carbon fiber epoxy composite was measured. The grinding temperature and surface roughness were also measured to investigate the surface grinding characteristics of the composites. The experiments were performed both under dry and wet grinding conditions with respect to cutting speed, feed speed, depth of cut and stacking angle. From the experimental investigation, the optimal conditions for the composite surface grinding were suggested.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.7
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• pp.178-188
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• 1995

A study on the temperature distribution of tungsten carbide alloy steel(WC-Co) in surface grinding was conducted to improve the surface finish and to find optimum grinding conditions which would lead to efficient grinding operation by theoretical finite element method analysis and experimental test of workpiece under various conditions. Based on the comparixion of test results and FEM analysis data, it is concluded that the FEM computer simulation of heat transfer is useful in predicting the temperature distribution of test material that the increase of temperature is more infuleneced by the grinding depth than the grinding speed. And that the grinding energy flux of dey grinding is 4 to 6 time greater than wet grinding regardless of grinding speed and finally that the heat transfer does not take place in depth deeper than 3mm from the grinding surface.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.441-446
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• 2000

Although the net-shape molding of composites is generally recommended, molded composites frequently required cutting or grinding due to the dimensional inaccuracy for precision machine elements. During the composite machining operations such as cutting and grinding, the temperature at the grinding area may increase beyond the allowed limit due to the low thermal conductivity of composites, which might degrade the matrix of composite. Therefore, in this work, the temperature at the grinding point during surface grinding of carbon fiber epoxy composite was measured. The grinding temperature and surface roughness were also measured to investigate the surface grinding characteristics of the composited. The experiments were performed both under dry and wet grinding conditions with respect to cutting speed, feed speed, depth of cut and stacking angle. From the experimental investigation, the optimal conditions for the composite plain grinding were suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.857-861
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• 1997

In discontinuous wheel grinding, temperature is different form conventional grinding. The characteristics of discontinuous grinding with respect to various slotted wheel were compared with those of general grinding. Thermal conditions vary with intermittent ratio, direction of fluid supply for discontinous wheel. According to three direction of grinding fluid supply and intermittent ratio,temperature and surface roughness were analyzed.

• 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 of Safety
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• v.5 no.1
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• pp.31-39
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• 1990

In this paper, the influence of the table speed, metal removal rate and grinding fluid on long wheel workpiece contact zone at high effect grinding was investigated by theoretical analyses and measuring the temperature, and discussed by the temperature distribution in grinding surface layer. Main results obtained are as follows, 1) Rega.dless of the table speed, the temperature gap of the workpiece(heat influx) is about 6-8 times as high in dry condition as in wet condition. 2) Good grinding condition can be obtained owing to the effect of grinding fluid without any burning defect under the condition of the metal removal rate(1.0mm$^3$/mm.s) in case of wet grinding. 3) When the depth from the surface layer is about 1.25-1.5mm under the condition of the slow table speed, surface temperature goes up higher as the table speed slows down, because long contact time is laked at the surface layer. 4) In case of the same metal removal rate, the lower the table speed becomes, the higher the surface temperature is, because grinding depth has a far more influence on wheel workpiece contact zone than the table speed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.899-902
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• 1997

The heat generated during surface grinding process can lead to elevate a grinding temperature, which cause the thermal damage to the workpiece material. Because of this reason, it is important to be able to predict the temperature which is occurred during grinding. The process parameters, therefore, should be adjusted properly to yield the acceptable workpiece temperature. In this study, we conducted an experimentation to obtain and also to analyze the temperature distribution of the workpiece with accordance in varying the grinding condition. For measuring the workpiece temperature, thermocouples of the CA type were inserted into the predetermined locations of the workpiece.