Journal of Powder Materials (한국분말재료학회지)

The Korean Powder Metallurgy & Materials Institute (한국분말재료학회 (*구 분말야금학회))
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Fabrication of Porous Tungsten by Freeze Casting and Vacuum Drying of WO3/Tert-butyl Alcohol Slurry

WO3/Tert-butyl alcohol 슬러리의 동결주조와 진공분위기 건조를 이용한 텅스텐 다공체 제조

  • Heo, Youn Ji (Department of Materials Science and Engineering, Seoul National University of Science and Technology) ;
  • Lee, Eui Seon (Department of Materials Science and Engineering, Seoul National University of Science and Technology) ;
  • Oh, Sung-Tag (Department of Materials Science and Engineering, Seoul National University of Science and Technology) ;
  • Jeong, Young-Keun (Graduate School of Convergence Science, Pusan National University)
  • 허연지 (서울과학기술대학교 신소재공학과) ;
  • 이의선 (서울과학기술대학교 신소재공학과) ;
  • 오승탁 (서울과학기술대학교 신소재공학과) ;
  • 정영근 (부산대학교 융합학부)
  • Received : 2022.04.08
  • Accepted : 2022.04.22
  • Published : 2022.04.28
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Abstract

The synthesis of porous W by freeze-casting and vacuum drying is investigated. Ball-milled WO3 powders and tert-butyl alcohol were used as the starting materials. The tert-butyl alcohol slurry is frozen at -25℃ and dried under vacuum at -25 and -10℃. The dried bodies are hydrogen-reduced at 800℃ and sintered at 1000℃. The XRD analysis shows that WO3 is completely reduced to W without any reaction phases. SEM observations reveal that the struts and pores aligned in the tert-butyl alcohol growth direction, and the change in the powder content and drying temperature affects the pore structure. Furthermore, the struts of the porous body fabricated under vacuum are thinner than those fabricated under atmospheric pressure. This behavior is explained by the growth mechanism of tert-butyl alcohol and rearrangement of the powders during solidification. These results suggest that the pore structure of a porous body can be controlled by the powder content, drying temperature, and pressure.

Keywords

Acknowledgement

이 논문은 부산대학교 기본연구지원사업(2년)에 의하여 연구되었음.

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