• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.3
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• pp.77-82
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• 2014

In this study, we carried out the interrupted cutting of carbon steel for a machine structure (SM45C) with a CVD-coated tool and conducted an ANOVA test and a confidence interval analysis to find factors influence the surface roughness and to obtain a regression equation. We found that factor which mostly affects the surface roughness during interrupted cutting was the feed rate. The cutting speed and depth of the cut only had small effect on the surface roughness. From the result of a multi-regression analysis during an interrupted cutting experiment, we obtained regression equation. Its coefficient of determination was 0.918, indicating that the regression equation was predictable. Compared to continuous cutting, if the feed rate increases, the surface roughness will also increase during interrupted cutting.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.6
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• pp.73-79
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• 2020

Although engineering plastics that are light-weight and have excellent mechanical performance have been widely applied in various industries in place of steel structures to reduce the burden of cost and time, there have been few studies related to their surface roughness. This study aims to evaluate the optimal effects of feed rate, cutting speed, and depth of cut as cutting parameters as well as nose angle on the surface characteristics of MC nylon in CNC lathe machining. To determine the best conditions under different nose radii, the experiments were performed based on the Taguchi L9(34) orthogonal array method, in which the resulting data was analyzed using the S/N ratio and ANOVA. Results indicate that the most significant contribution was feed rate followed by nose angle and cutting speed, whereas the depth of cut did not influence the performance. This study demonstrates that the suggested method for improving the surface finishing of MC nylon is efficient compared with results obtained from experimentation and prediction.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.101-113
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• 2007

A landslide was occurred due to soil cutting for construction to expand the Donghae express highway in Dong-hae-City, Korea. The total area of the landslide was about $9,550m^2$ with 100 m of width and 87m of height. The landslide was occurred due to the internal factor of the unstable geological structure including the clay layer and the external factor of continuous heavy rainfalls. As the result of field instrumentation during the landslide, the horizontal displacement of the slope ground increases with increasing the accumulated rainfall by continuous rainfall during the rainy season. Also, the depth of sliding failure was decided by the horizontal displacement distribution during landslide occurrence. It makes sure that the horizontal displacement starts from the depth of sliding failure and the depth of sliding failure matches well with the location of the clay layer. As the slope stability analysis using Bishop's Simplified Method at the landslide area, the safety factor of slope during the rainy season was 0.53. This safety factor of slope was enough to trigger the landslide at this area. The depth of sliding failure obtained by analytical method matches well with the depth of the clay layer.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.4 no.3
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• pp.67-76
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• 1995

An experimental study of hot machining has performed to improve the machinability of Inconel718. This experiment used plasma are for heating materials and Whisker0reinforce aluminum oxide ceramic tool insert. An assembled plasma heating system are described and experimental results from both conventional and plasma hot machining of Inconel 718 are compared. The experiments with plasma heating demonstrated the following effectiveness. 1)The cutting force was reduced with increasing surface temperature of workpiece from 450$^{\circ}C$ up to 720$^{\circ}C$ as much as approximately from 20 to 40%. 2) Surface roughness(Ra) was improved by as much as a factor 2 in case of one pass cutting with new ceramic tool inserts.3) The depth of cut notch were at promary cutting tool was significantly reduced.

• Land and Housing Review
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• v.14 no.3
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• pp.137-144
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• 2023

The amount of soil cutting, transported, and filing up the soil in the project area is considered to change the volume depending on the condition of the soil; the volume change rate of the soil is calculated by collecting undisturbed samples below 1 m to 2.0 m above the surface through test pits. In this study, large-scale field tests are carried out. There are areas with an excavation depth of 10m or more, but some errors have occurred in calculating the soil volume by uniformly applying the soil conversion factor for a depth of 1 to 2 m. According to the field tests, the earthwork volumes applied with the soil conversion factor for each depth increase by 3.9 to 9.4% compared to the soil volume applied uniformly with that of 2 m depth.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.04b
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• pp.137-141
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• 1993

In the case of a boring bar, the vibration amplitude is generallylarge due to its high slenderness. The boring bat is then modelled as a cantilever with dynamic force acting at the free end and a generalized model of nonlinear continous system is obtained. The Analysis of model is conducted for the specific case with a zero side cutting edge angle. The dynamic behaviour is investigated for machining processes in which the the overlap factor of regenerative effect is considered. The vibration characteristics of boring bar depth of cut rather than feed rate in given slenderness.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1309-1316
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• 2003

The general dicing process cuts a semiconductor wafer to lengthwise and crosswise direction by using a rotating circular diamond blade. But products with inferior quality are produced under the influence of several parameters in dicing process such as blade, wafer, cutting water and cutting conditions. Moreover we can not apply this dicing method to GaN wafer, because the GaN wafer is harder than the other wafer such as SiO2, GaAs, GaAsP, and AlGaAs. In order to overcome this problem, development of a new dicing process and determination of dicing parameters are necessary. This paper describes a new wafer dicing method using fixed diamond scriber and precision servo mechanism and determination of several parameters - scribing depth, scribing force, scriber inclined angle, scribing speed, and factor for scriber replacement - for a new dicing machine using scriber.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.80-87
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• 1995

An experimental study of hot machining has performed to improve themachinability of Inconel 718. This experiment used plasma arc for heating materials and Whisker-reinforced aluminum oxide ceramic tool insert. An assembled plasma heating system are described and experimental results obtained from bothconventional and plasma hot machining of Iconel 718 are compared. Turning experiments with plasma heating demonstrated the following effectiveness. 1) The cutting force was reduced with increasing surface temperature of workpiece from 450 .deg. C up to 720 .deg. C as much as approximately from 20 to 40%. 2) Surface roughness(Ra) was improved by as much as a factor 2 in case of one pass cutting with new ceramic tool inserts. 3) The depth of cut notchwear at primarycutting tool was singificantly reduced.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.2
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• pp.218-225
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• 2003

The general dicing process cuts a semiconductor wafer to lengthwise and crosswise direction by using a rotating circular diamond blade. However, inferior goods may be made under the influence of several parameters in dicing process such as blade, wafer, cutting water and cutting conditions. Moreover we can not apply this dicing method to a GaN wafer, because the GaN wafer is harder than other wafers such as SiO$_2$, GaAs, GaAsP, and AlGaAs. In order to overcome this problem, development of a new dicing process and determination of dicing parameters are necessary. This paper describes determination of several parameters - scribing depth, scribing force, scriber inclined angle, scribing speed, and factor for scriber replacement - for a new dicing machine using a scriber.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.164-167
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• 2002

The general dicing process cuts a semiconductor wafer to lengthwise and crosswise direction by using a rotating circular diamond blade. But inferior goods are made under the influence of several parameters in dicing process such as blade, wafer, cutting water and cutting conditions. Moreover we can not applicable this dicing method to GaN wafer, because the GaN wafer is harder than the other wafer such as SiO$_2$, GaAs, CaAsP, and AlCaAs. In order to overcome this problem, development of a new dicing process and determination of dicing parameters are necessary. This paper describes determination of several parameters - scribing depth, scribing force, scriber inclined angle, scribing speed, and factor for scriber replacement - for a new dicing machine using scriber.