Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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Effects of particle size and oxygen contents on ZrB2 powder for densification

ZrB2 분말의 입도 및 산화도가 치밀화에 미치는 영향

  • Jung, Se-Hyuk (Division of Materials Science Engineering, Hanyang University) ;
  • Choi, Sung-Churl (Division of Materials Science Engineering, Hanyang University)
  • 정세혁 (한양대학교 신소재공학부) ;
  • 최성철 (한양대학교 신소재공학부)
  • Received : 2012.08.16
  • Accepted : 2012.09.14
  • Published : 2012.10.31
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Abstract

In this study, two pretreatment methods were used to improve the sinterability of zirconium diboride ($ZrB_2$). As a mechanical treatment, as-received $ZrB_2$ powder was crushed using SPEX mill from an average size of $2.61{\mu}m$ to $0.35{\mu}m$. As a chemical treatment, oxygen contents of $ZrB_2$ powder were decreased from 4.20 wt% to 2.22 wt% using a dilute hydrofluoric solution. The relative density of sintered $ZrB_2$ increased with decreasing particle size and oxygen contents. But it is considered that particle size is more effective than oxygen contents for $ZrB_2$ densification. Through the two pretreatment processes, we produced sintered $ZrB_2$ ceramic with a full density without sintering additives. The sinterability of $ZrB_2$ was improved by using mechanical and chemical pretreatment methods.

본 연구에서는 zirconium diboride($ZrB_2$)의 소결성 향상을 위해 두 가지 전처리 공정을 사용하였다. 물리적 전처리 공정으로 SPEX mill을 사용하여 as-received $ZrB_2$ powder의 입도를 $2.61{\mu}m$에서 $0.35{\mu}m$까지 감소시킬 수 있었다. 화학적 전처리 공정으로 희석된 불산 용액을 사용하여 $ZrB_2$ powder의 산화도를 4.20 wt%에서 2.22 wt%까지 감소시킬 수 있었다. 소결된 $ZrB_2$의 상대 밀도는 입도와 산화도가 감소함에 따라 증가하였다. $ZrB_2$의 치밀화에는 산화도 보다 입도의 영향이 더 크다는 것을 확인하였다. 두 가지 전처리 공정을 통해 소결 조제의 사용 없이 치밀한 $ZrB_2$ 소결체를 제조하였다. 물리적 화학적 전처리 공정을 사용함으로써 $ZrB_2$의 소결성을 향상시킬 수 있었다.

Keywords

References

  1. R. Telle, L.S. Sigl and K. Takagi, "Boride-Based Hard Materials" in Handbook of Ceramic Hard Materials, R. Riedel Ed. (Wiley-VCH, Weinheim Germany, 2000) p. 802.
  2. W.G. Fahrenholtz, G.E. Hilmas, I.G. Talmy and J.A. Zaykoski, "Refractory diborides of zirconium and hafnium", J. Am. Ceram. Soc. 90(5) (2007) 1347. https://doi.org/10.1111/j.1551-2916.2007.01583.x
  3. R.A. Cutler, "Engineering Properties of Borides" in Ceramics and Glasses: Engineered Materials Handbook, S. J. Schneider Jr. Ed., Vol. 4 (ASM International, Materials Park, Ohio, 1991) p. 787.
  4. S. Zhu, W.G. Fahrenholtz, G.E. Hilmas and S.C. Zhang, "Pressureless sintering of carbon-coated zirconium diboride powders", Mater. Sci. Eng. A 459(1-2) (2007) 167. https://doi.org/10.1016/j.msea.2007.02.116
  5. M. Thompson, W.G. Fahrenholtz and G.E. Hilmas, "Effect of starting particle size and oxygen content on densification of $ZrB_{2}$", J. Am. Ceram. Soc. 94(2) (2011) 429. https://doi.org/10.1111/j.1551-2916.2010.04114.x
  6. J. Zou, G.J. Zhang, S.K. Sun, H.T. Liu, Y.M. Kan, J.X. Liu and C.M. Xu, "$ZrO_{2}$ removing reactions of groups IV-VI transition metal carbides in $ZrB_{2}$ based composites", J. Eur. Ceram. Soc. 31(3) (2011) 421. https://doi.org/10.1016/j.jeurceramsoc.2010.10.011
  7. W.G. Fahrenholtz, G.E. Hilmas, S.C. Zhang and S. Zhu, "Pressureless sintering of zirconium diboride: Particle size and additive effects", J. Am. Ceram. Soc. 91(5) (2008) 1398. https://doi.org/10.1111/j.1551-2916.2007.02169.x
  8. V. Lowalekar and S. Raghavan, "Etching of zirconium oxide, hafnium oxide, and hafnium slilcates in dilute hydrofluoric acid solutions", J. Mater. Res. 19(4) (2004) 1149. https://doi.org/10.1557/JMR.2004.0149
  9. P.L. Brown, E. Curti, B. Grambow and C. Ekberg, "Chemical Thermodynamics of Zirconium" in OECD Chemical Thermodynamics Series, F.J. Mompean Ed., Vol. 8 (Elsevier, Amsterdam, 2005).
  10. P.J. Jansson, C.L. Hawkins, D.B. Lovejoy and D.R. Richardson, "The iron complex of Dp44mT is redoxactive and induces hydroxyl radical formation: An EPR study", J. Inorg. Biochem. 104(11) (2010) 1224. https://doi.org/10.1016/j.jinorgbio.2010.07.012
  11. A.L. Chamberlain, W.G. Fahrenholtz and G.E. Hilmas, "Pressrueless sintering of zirconium diboride", J. Am. Ceram. Soc. 89(2) (2006) 450. https://doi.org/10.1111/j.1551-2916.2005.00739.x
  12. R.A. Smith, "Boric Oxide, Boric Acid, and Borates" in Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., W. Gerhartz Ed., Vol. A4 (VCH, Weinheim, 1985) p. 265.