통합 검색 | Korea Science

Lee, Jongchan;Whan Chio;Woojin Sim;Yongky Kang;Eunha Hwang;Lee, Taewon;Sangbaek Ha;Kim, Sunghun
- 한국공작기계학회논문집
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- 제10권3호
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- pp.90-96
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- 2001
Experimental investigations were carried out to find the characteristics of grinding of ceramics. Grinding mechanisms of ceramics were inspected through the microscopic examination. It has been found that the specific grinding energy of ceramics is relatively low as compared to that of steels. The specific grinding energy affects the surface roughness and the residual stress of ground surface. the experimental results indicate that the rougher surface finish and higher compressive residual stress are obtained at lower specific grinding energy. The surface roughness and the residual stress of the ground surface have significant effects on the strength of ground piece of ceramics.
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Gong, Y.F.;Birosca, S.;Kim, Han S.;De Cooman, B.C.
- Corrosion Science and Technology
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- 제7권1호
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- pp.1-5
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- 2008
The gas atmosphere in continuous annealing and galvanizing lines alters both composition and microstructure of the surface and sub-surface of sheet steel. The formation and morphology of the oxides of alloying elements in High Strength Interstitial Free (HS-IF), Dual Phase (DP) and Transformation-Induced Plasticity (TRIP) steels are strongly influenced by the furnace dew point, and the presence of specific oxide may result in surface defects and bare areas on galvanized sheet products. The present contribution reviews the progress made recently in understanding the selective formation of surface and subsurface oxides during annealing in hot dip galvanizing and conventional continuous annealing lines. It is believed that the surface and sub-surface composition and microstructure have a pronounced influence on galvanized sheet product surface quality. In the present study, it is shown that the understanding of the relevant phenomena requires a combination of precise laboratory-scale simulations of the relevant technological processes and the use of advanced surface analytical tools.
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