• Journal of the Korean Institute of Gas
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• v.10 no.2 s.31
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• pp.40-46
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• 2006

In this paper, the optimized design of a rectangular O-ring groove has been analyzed for a maximum Cauchy stress and maximum strain using the Taguchi method. This method may efficiently optimize the design parameters for an O-ring groove of a LPG filling unit. The computed FEM results indicate that the optimized design parameters can only be drawn by nine experimental numbers of iterations when the Taguchi design technique has been employed with a finite element method. This means that the Taguchi design method is very useful for the optimization design of O-ring rectangular groove geometry. Based on the computed FEM results by the Taguchi design technique, the dimensions of a groove geometry are given as h=2.5 mm, d=2.74 mm, c=0.15 mm, and w=3.0 mm. In this study, the initial compression ratio of O-rings is recommended as 8.7% for a gas supply pressure of 18 $kg/cm^2$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.3 s.234
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• pp.432-438
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• 2005

CMP characteristics such as material removal rate and edge effect were measured and investigated in accordance with pad grooving effect, groove width, depth and pitch. GSQ (Groove Stiffness Quotient) and GFQ (Groove Flow Quotient) were proposed to estimate pad grooving characteristics. GSQ is defined as groove depth(D) divided by pad thickness(T) and GFQ is defined as groove width(W) divided by groove pitch(P). As GFQ value increased, material removal rate increased some point but gradually saturated. It seems that material removal rate is not affected by each parameter respectively but by interaction of these parameters such as groove dimensions. In addition, an increase in GFQ and GSQ causes edge effect to be improved. Because, pad stiffness decreases as GSQ and GFQ increase. In conclusion, groove influences relative pad stiffness although original mechanical properties of pad are unchanged by grooving. Also, it affects the flow of slurry that has an effect on the lubrication regime and polishing results. The change of groove dimensions has influence on pad stiffness and slurry flow, so that polishing results such as removal rate and edge effect become changed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.127-128
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• 2010

• Tribology and Lubricants
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• v.32 no.4
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• pp.119-124
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• 2016

In the sapphire wafering process, lapping is a crucial operation in order to reduce the damaged layer and achieve the target thickness. Many parameters, such as pressure, velocity, abrasive, slurry and plate, affect lapping characteristics. This paper presents an experimental investigation on the effect of the plate groove on the material removal rate and roughness of the wafer. We select the spiral pattern and rectangular type as the groove shapes. We vary the groove density by controlling the groove shape dimension, i.e., the groove width and pitch. As the groove density increases to 0.4, the material removal rate increases and gradually reaches a saturation point. When the groove density is low, the pressing load is mostly supported by the thick film, and only a small amount acts on the abrasives resulting to a low material removal rate. The roughness decreases on increasing the groove density up to 0.3 because thick film makes partial participations of large abrasives which make deep scratches. From these results, we could conclude that the groove affects the contact condition between the wafer and plate. At the same groove density, the pitch has more influence on reducing the film thickness than the groove width. By decreasing the groove density with a smaller pitch and larger groove width, we could achieve a high material removal rate and low roughness. These results would be helpful in understanding the groove effects and determining the appropriate groove design.