• 한국세라믹학회지
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• 제44권7호
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• pp.358-361
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• 2007

Well-ordered mesoporous SiCBN ceramics have been successfully synthesized by infiltrating a polymeric precursor, which was prepared from borazine and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane via a hydroboration reaction, into a mesoporous carbon (CMK-3) as a hard template. This was followed by pyrolysis at $1400^{\circ}C$ under nitrogen gas and subsequent oxidative removal of the carbon template without chemical etching. The prepared mesoporous SiCBN ceramic was characterized by a small-angle XRD, TEM, and BET surface area. The resulting mesoporous SiCBN ceramic revealed a BET surface area of $275 m^2g^{-1}$ and a pore volume of $0.8 cm^3 g$ with no crystallization.

• 대한기계학회논문집A
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• 제21권9호
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• pp.1520-1530
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• 1997

Machining pressed compacts of ceramic and WC-Co materials can be the most cost effective way of forming the bodies prior to sintering when the required number of pieces is small. In this study, in order to clarify the machinability for turning, the $Si_3N_4$ and the WC-Co green compacts unsintered were machined under different cutting conditions with various tools. Absorbing chips by vacuum hose decreases tool wear. The tool wear becomes larger in the order of the ceramic, CBN and cemented carbide tools in machining the $Si_3N_4$ green compacts. In machining the WC-Co green compacts, the tool wear becomes larger in the order of the ceramic, cemented carbide and CBN tools. The land of cutting edge does not affect tool wear. When machining with cemented carbide tool, the tool wear i equal cutting length is nearly identical in spite of the increase of cutting spee, and the roughness of machined surface was the best in the cutting speed of 90 m/min. The tool wear decreases with the increase of rake angle and relief angle and with the decrease of nose radius. The machined surfaces become worse with the increase of feed rate and depth of cut, and with the decrease of rake angle and relief angle. The tool wear is not affected by the feed and depth of cut.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.154.1-154
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• 2003