• Journal of Conservation Science
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• v.19
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• pp.57-66
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• 2006

The rock consisting the Naju-Dongmunoi-Seogdanggan (Stone Stele)(Treasure number 49) is biotite granite of medium to coarse grains which might be taken from nearby area. The rock is mainly composed of quartz, plagioclase, alkali feldspar and biotite. Due to strong weathering grail peel-off and surface exfoliation are well developed. The rock surface is changed into pale brown or pale black colors according to weathering, organism and weathering product of iron band. Major deterioration phenomena are grain peel-off, surface exfoliation, cracks and damage which may be originally classified into weathering, effect of weathering product of iron band, organisms, structural unstabilities and impact.

• Journal of Conservation Science
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• v.25 no.2
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• pp.131-145
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• 2009

Goryeong Yangjeondong Petroglyph on the joint face of the bedrock (6m in width, 3m in height) composed of the green sandstone has circles and shield pattern sculptures. The rock is mainly composed of quartz, feldspar, chlorite, illite and calcite with the clay minerals. These clay minerals occur as pore lining, replacement of component and pore fillings. Investigated the weathering aspects including the connection between soluble salt and rock weathering and the stability of the bedrock with petroglyphs. The Major deterioration aspect are grain peel-off, surface exfoliation, cracks and damage. And the bedrock where the joints and cracks advance is interpreted with the fact that has the possibility of the falling rock. For conservation, adhesive need to cover crack and damage and consolidation is necessary in the surface which becomes weak.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.10
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• pp.113-123
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• 1990

Tungsten film was deposited on the single crystal silicon wafer in a low pressure chemical vapor deposition reactor from silane and tungsten hexafluoride in the temperature range of $250-400^{\circ}C$ Deposition rate was found to be determined by the mass transfer rate of reactants from the gas phase to the safter surface. It was found out that tungsten films deposited contained about 3 atomic $\%$ of silicon and that the crystallinity and the grain size increased as the deposition temperature was increased. The resistivity of the film was measured to be in the range of $7~25{\mu}{\Omega}-cm$ and decreased with increasing deposition temperature. The adhesion of the tungsten film on a silicon surface was measured by the tape peel off test and it was improved with increasing deposition temperature. From the analysis of the gas composition, the reaction pathway to form $SiF_{4}$ and $H_{2}$ was found to be more favorable than HF formation.

• Journal of the Korean Ceramic Society
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• v.41 no.10 s.269
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• pp.728-734
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• 2004

The effect of microstructure of WC-Co substrates which have different WC grain sizes from submicron to 5 $\mu$m on the diamond-substrate adhesion strength was investigated. The substrates were pre-treated by two methods : chemical etching with Murakami's solution and subsequently with $H_2SO_4$, and thermal heat-treatment. The adhesion strength was estimated by degree of peeling after Rockwell indentation. Diamond films of 20 $\mu$m thickness deposited on the heat-treated substrates showed an excellent adhesion strength at the load of 100 kg, which ascribed to the large and elongated WC grains. However, the cutting edge of insert was deformed after heat treatment and the surface morphology of heat treated substrate strongly affected on the surface roughness of the deposited diamond films. On the contrary, the diamond film of 10 $\mu$m in thickness on the chemically etched substrates of average WC grain size over 2 $\mu$m showed good adhesion strength enough not to peel-off under a load of 60 kg. Especially, the substrate of average WC grain size over 5 $\mu$m exhibited much improved reliability of adhesion comparing with the substrate of average grain size under 2 $\mu$m. No substrate deformation was observed in this case after the chemical etching, which is more advantageous and more practical in terms of precious machining than the heat treatment case.

• Journal of Conservation Science
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• v.25 no.4
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• pp.347-361
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• 2009

The Pohang Chilpori is the area with abundant petroglyphs in Korea. The form of the shield, female sex organs, and yut board on the outcrops or float rocks which are composed of the rhyolitic rock are engraved on Chilpori and Shinheungri Petroglyphs. The rhyolitic rock is composed of the phenocryst and groundmass with quartz and feldspar. The rock surface shows mostly yellowish brown color and the rock surface is very irregular by serious weathering, and illite and kaolinite, a kind of the clay minerals, are produced. Deterioration aspects are mainly of surface exfoliation, grain peel-off, damages, scribbling. Chilpori Petroglyph (1) plane has been eroded by running water, in (2) plane has been abrased is on the rock surface, in (3) plane shows surface exfoliation and the various part of the rock surface in plane (4) has become the soil. The corrasion and black phenomenon of the Shinheungri Petroglyph (1) plane was formed by running water, and surface exfoliation and scribbling in plane (2) is serious. Deterioration factors are geomorphologic states, plants, rock of weak to weathering, and artificial influence such as a scribbling and a forest fire. For conservation of the these petroglyphs, study for rock surface conservation and the arrangement of around petroglyphs and construction of water wall are necessary.