화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Korean Journal of Materials Research, Vol.25, No.11, 602-606, November, 2015
DOI10.3740/MRSK.2015.25.11.602  Export Citation
구형 PMMA와 WO3 분말이 혼합된 Camphene 슬러리의 동결건조에 의한 W 다공체 제조
Fabrication of Porous W by Freeze-Drying Process of Camphene Slurries with Spherical PMMA and WO3 Powders
이한얼, 전기철, 김영도1, 석명진2, 오승탁†
  • 서울과학기술대학교 신소재공학과
  • 1한양대학교 신소재공학부
  • 2강원대학교 재료금속공학과
Han-Eol Lee, Ki Cheol Jeon, Young Do Kim1, Myung-Jin Suk2, and Sung-Tag Oh†
  • Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 139-743, Korea
  • 1Division of Materials Science and Engineering,, Hanyang University, Seoul 133-791, Korea
  • 2Department of Materials and Metallurgical Engineering, Kangwon National University, Samcheok 245-711, Korea
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Porous W with spherical and directionally aligned pores was fabricated by the combination of sacrificial fugitives and a freeze-drying process. Camphene slurries with powder mixtures of WO3 and spherical PMMA of 20 vol% were frozen at .25 oC and dried for the sublimation of the camphene. The green bodies were heat-treated at 400 oC for 2 h to decompose the PMMA; then, sintering was carried out at 1200 oC in a hydrogen atmosphere for 2 h. TGA and XRD analysis showed that the PMMA decomposed at about 400 oC, and WO3 was reduced to metallic W at 800 oC without any reaction phases. The sintered bodies with WO3-PMMA contents of 15 and 20 vol% showed large pores with aligned direction and small pores in the internal walls of the large pores. The pore formation was discussed in terms of the solidication behavior of liquid camphene with solid particles. Spherical pores, formed by decomposition of PMMA, were observed in the sintered specimens. Also, microstructural observation revealed that struts between the small pores consisted of very fine particles with size of about 300 nm.
Keywords:Porous W with spherical and directionally aligned pores was fabricated by the combination of sacrificial fugitives and a freeze-drying process. Camphene slurries with powder mixtures of WO3 and spherical PMMA of 20 vol% were frozen at .25 oC and dried for the sublimation of the camphene. The green bodies were heat-treated at 400 oC for 2 h to decompose the PMMA;then;sintering was carried out at 1200 oC in a hydrogen atmosphere for 2 h. TGA and XRD analysis showed that the PMMA decomposed at about 400 oC;and WO3 was reduced to metallic W at 800 oC without any reaction phases. The sintered bodies with WO3-PMMA contents of 15 and 20 vol% showed large pores with aligned direction and small pores in the internal walls of the large pores. The pore formation was discussed in terms of the solidication behavior of liquid camphene with solid particles. Spherical pores;formed by decomposition of PMMA;were observed in the sintered specimens. Also, microstructural observation revealed that struts between the small pores consisted of very fine particles with size of about 300 nm
  1. Liu PS, Liang KM, J. Mater. Sci., 36(21), 5059 (2001)
  2. Banhart J, Prog. Mater. Sci., 46(6), 559 (2001)
  3. Suk MJ, Kwon YS, J. Korean Powder Metall. Inst., 8, 215 (2001)
  4. Nakajima H, Prog. Mater. Sci., 52(7), 1091 (2007)
  5. Ohji T, Fukushima M, Intern. Mater. Rev., 57, 115 (2012)
  6. Yang DH, Hur BY, Yang SR, J. Alloy. Compd., 461, 221 (2008)
  7. Deng ZY, Yang JF, Beppu Y, Ando M, Ohji T, J. Am. Ceram. Soc., 85(8), 1961 (2002)
  8. Song IH, Kwon IM, Kim HD, Kim YW, J. Eur. Ceram. Soc., 30, 2671 (2010)
  9. Fukasawa T, Ando M, Ohji T, Kanzaki S, J. Am. Ceram. Soc., 84(1), 230 (2001)
  10. Jeon KC, Kim YD, Suk MJ, Oh ST, J. Korean Powder Metall. Inst., 22, 129 (2015)
  11. Oh ST, Kim YD, Suk MJ, Mater. Lett., 139, 268 (2015)
  12. Mengual O, Meunier G, Cayre I, Puech K, Snabre P, Talanta, 50, 445 (1999)
  13. Kim NH, Song H, Choi SC, Choa YH, J. Korean Powder Metall. Inst., 16, 262 (2009)
  14. Wilken TR, Morcom WR, Wert CA, Woodhouse JB, Metall. Mater. Trans. B-Proc. Metall. Mater. Proc. Sci., 7, 589 (1976)
  15. Lee YS, Oh ST, Korean J. Mater. Res., 21(9), 520 (2011)
  16. Deville S, Adv. Eng. Mater., 10, 155 (2008)
  17. Kim DG, Oh ST, Jeon H, Lee CH, Kim YD, J. Alloy. Compd., 354, 239 (2003)