• 제목/요약/키워드: Fine ceramics

검색결과 244건 처리시간 0.022초

화인세라믹스의 고능률적 평면 연삭가공을 위한 실험적 연구(I) (Stduy on the Surface Grinding Machining of Fine-ceramics with high efficiency)

  • 강재훈;이재경
    • 한국정밀공학회지
    • /
    • 제7권4호
    • /
    • pp.40-54
    • /
    • 1990
  • Recently, Fine Ceramics have been concerned significantly with some excellent properties and many functions as new industrial materials to the industry at alrge. For the manufacture of Fine Ceramics, sintering is essential process. Thus the most of a Fine Ceramics used for precision parts are in need of machining proces. It is, however, very difficult to manufacture the Advanced Ceramics with high efficiency because they have not only high strength and brittl- eness but also high hardness. In present research, experiments are carried out to obtain the basic knowledge of Fine Ceramics grinding with high efficiency. Representative advanced ceramics, such as A1/sub 2/0/sub 3/, Z/sub r/O/sub 2/SiC snd Si/sub 2/N/sub 4/are ground with diamond wheels using conventional surface grinding machine. This research is carried out for the purpose of saving machining technology required for manufactiring Fine Ceramics parts

  • PDF

Bending Strength of Textured Alumina Prepared by Slip Casting in a Strong Magnetic Field

  • Suzuki, Tohru S.;Uchikoshi, Tetsuo;Morita, Koji;Hirage, Keijiro;Sakka, Yoshio
    • 한국분말야금학회:학술대회논문집
    • /
    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
    • /
    • pp.1099-1100
    • /
    • 2006
  • The mechanical properties of ceramics materials can be tailored by designing their microstructures. We have reported that development of texture can be controlled by slip casting in a strong magnetic field followed by heating even for diamagnetic ceramics such as alumina. A strong magnetic field of 12T was applied to the suspension indcuding alumina powder to rotate each particle during slip casting. The sintering was conducted at the desired temperature in air without a magnetic field. C-axis of alumina was parallel to the magnetic field. Bending strength of textured alumina depended on the direction of oriented microstructure.

  • PDF

THE PREPARTION AND CHAEATERIZATION OF ALUMINA UF MEMBRANE BY SOL-GEL PROCESS

  • Choi, Y. H.;Paik, J. S.;Kim, H. C.;Lee, S. B.;Oh-kim, E. O.
    • 한국막학회:학술대회논문집
    • /
    • 한국막학회 1991년도 추계 총회 및 학술발표회
    • /
    • pp.29-33
    • /
    • 1991
  • Alumina UF membranes were prepared by sol-gel process and their gas permeabilities were characterized. Alumina MF membrane with average pore diameter about 0.12$\mu$m and tubular shape was used as a support. Gas permeation measurements of helium and nitrogen gas exhibited the permeabilities of 1.58 $\times$ 10E-6 and $0.63 \times 10E-6 cc\cdot cm(STP)/cm^2\cdot sec \cdot cmHg$, respectively. The permeability ratio was 2.5. This means the gas permeation is fully governed by knudsen diffusion mechanism.

  • PDF

파인 세라믹 ($Al_2O_3$)의 被削性에 관한 硏究 (A Study on the Machinability of Fine Ceramics (($Al_2O_3$)))

  • 김성겸;이용성
    • 대한기계학회논문집
    • /
    • 제13권4호
    • /
    • pp.604-610
    • /
    • 1989
  • 본 연구는 알루미나계 세라믹의 소결 다이아몬드 공구로 절삭시의 칩의 형태 와 절삭저항을 관찰하였다. 절삭 양식은 건식과 습식으로 하고, 여러 가지 적삭조건 에 따른 flank 마멸의 진행과정, 가공면의 표면거칠기에 미치는 영향 및 가공면의 크랙 상태를 조사형 현미경으로 확대 검출하여 가공상태를 정밀하게 조사, 측정하였 다.

실험적 방법에 의한 파인세라믹스의 연삭성에 관한 연구 (A study on the Grindability of Fine Ceramics by Experimental Method)

  • 김성겸
    • 반도체디스플레이기술학회지
    • /
    • 제10권3호
    • /
    • pp.35-42
    • /
    • 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.

Computer Simulation of Sintering and Grain Growth

  • Matsubara, Hideaki
    • 한국분말재료학회지
    • /
    • 제5권4호
    • /
    • pp.324-328
    • /
    • 1998
  • This paper is aimed to study the computer simulation of sintering process for ceramics by Monte Carlo and molecular dynamics methods. Plural mechanisms of mass transfer were designed in the MC simulation of sintering process for micron size particles; the transfer of pore lattices for shrinkage and the transfer of solid lattices for grain growth ran in the calculation arrays. The MD simulation was performed in the case of nano size particles of ionic ceramics and showed the characteristic features in sintering process at atomic levels. The MC and MD simulations for sintering process are useful for microstructural design for ceramics.

  • PDF