• Journal of the Korean Ceramic Society
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• v.47 no.2
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• pp.157-162
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• 2010

Effect of starting SiC particle size on nitridation rate and flexural strength of $Si_3N_4$-bonded-SiC (SNBSC) ceramics was investigated by using SiC particles of different size (${\sim}200\;{\mu}m$, ${\sim}100\;{\mu}m$ and ${\sim}45\;{\mu}m$). The specimen prepared from smaller SiC particles resulted in higher nitridation rate after nitridation at $1450^{\circ}C$, owing to the lower packing density in green body. The flexural strength showed maxima after 1-h nitridation for all specimens and then decreased with prolonged nitridation because of local densification-induced pore coarsening. The specimen prepared from smaller SiC particles showed better flexural strength because of smaller pore size and partly higher nitridation rate in the specimen. A maximal flexural strength of 29 MPa was obtained in the specimen with a density of $2.04\;g{\cdot}cm^3$, which was prepared from $45\;{\mu}m$-SiC particles.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.11a
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• pp.201-207
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• 2002

배가스 탈황 공정은 흡수제의 형태에 따라 습식과 건식, 반응생성물로부터 흡수제의 회수여부에 따라 재생법과 비재생법으로 분류할 수 있으며, 현재 전 세계적으로 상용화되고 있는 처리공정은 비재생 습식 석회석-석고 공정이 채택되어 전체 설치용량의 80% 이상을 점유하고 있다.(중략)

• Journal of the Semiconductor & Display Technology
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• v.10 no.3
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• pp.35-42
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• 2011

This paper describes the characteristics of high speed grinding and the influence of wheel surface speed V and a grindability of the grinding materials. The various fine ceramics pieces was ground by metal and vitrified bonded diamond wheel. The surface roughness of fine ceramics(Zirconia($ZrO_2$), Silicon Carbide(SiC), Silicon Nitride($Si_3N_4$), Alumina($Al_2O_3$)) decreases from $0.05{\mu}m(R_{max})$ to $0.025{\mu}m(R_{max})$ when the wheel speed at grinding point increases the wheel speed. Relation between the temperature at grinding point and surface roughness was linear. Abrasive jet machining(AJM), a specialized from of shot blasting, is considered one of the most helpful micro machining methods for hard and brittle materials such as glasses and ceramics by constant pressure grinding.