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Preparation of α-Si3N4 Powder in Reaction System Containing Molten Salt by SHS - Part 1. Synthesis of Powder

용융염계에서 자전연소합성법에 의한 α-Si3N4분말의 제조 - Part 1.분말의 합성

  • Published : 2004.03.01

Abstract

Si, NH$_4$Cl, NaN$_3$, NaCl, $N_2$ were used as raw materials for preparation of $\alpha$-Si$_3$N$_4$ powder. NH$_4$Cl and NaN$_3$ were used as additives, and NaCl was used as a diluent. Initial $N_2$ gas pressure in the SHS reactor was 60 atm. In preparation of $\alpha$-Si$_3$N$_4$, the reactivity and the properties of the products were examined with the various kinds of additives and the content of diluent. At first, the optimum reaction system for the preparation of $\alpha$-Si$_3$N$_4$ is examined and then the optimum composition was examined in the optimum reaction system. The optimum reaction system was Si-$N_2$-additive(NH$_4$Cl+NaN$_3$)-diluent(NaCl) and the optimum composition was 38 wt%Si+50 wt%(NH$_4$Cl+NaN$_3$)+12 wt%NaCl. The maximum fraction of $\alpha$-phase of Si$_3$N$_4$ produced in this condition was 96.5 wt% and the shape of the $\alpha$-Si$_3$N$_4$ produced in this condition was an irregular fiber with a length of 10 ${\mu}{\textrm}{m}$ and a diameter of 1 ${\mu}{\textrm}{m}$.

원재료로서 Si, NH$_4$Cl, NaN$_3$, NaCl을 사용하고 SHS법을 이용하여 $\alpha$-Si$_3$N$_4$ 분말을 제조하였다. NH$_4$Cl과 NaN$_3$는 첨가제로서, NaCl은 희석제로서 사용되었고 반응기내 최초 $N_2$ 압력은 60 atm이었다. $\alpha$-Si$_3$N$_4$분말을 제조함에 있어, 첨가제의 종류와 조성, 희석제의 첨가량에 따른 반응성 및 생성물의 특성을 조사하였는데, 우선 $\alpha$-Si$_3$N$_4$ 분말의 제조를 위한 최적의 반응계를 조사하였고, 최적의 반응계에서 최적의 조성을 확립하였다. 최적의 반응계는 Si-$N_2$-additive(NH$_4$C+NaN$_3$)-diluent(NaCl)이었고, 이때 최적의 조성은 38wt%Si+22.5wt%NH$_4$Cl+27.5wt%NaN$_3$+l2wt%NaCl이었다. 이 조건에서 생성된 최고 $\alpha$-Si$_3$N$_4$의 분율은 96.5wt%이었으며 생성된 분말의 입형은 길이가 약 10 $mu extrm{m}$이고 직경이 약 1 $\mu\textrm{m}$인 일방향으로 길게 성장한 부정형의 fiber 형태였다.

Keywords

References

  1. Ceramist v.4 no.3 R & D and Commercialization of Silicom Nitride Structural Ceramics D.S.Park;H.D.Kim;B.D.Han
  2. J. Kor. Ceram. Soc. v.39 no.1 Densification behavior of Reaction-Bonded Silicom Nitride Prepared by Using Coarse Si Powders J.S.Lee;J.H.Mun;B.D.Han;D.S.Park;H.D.Kim https://doi.org/10.4191/KCERS.2002.39.1.045
  3. J. Kor. Ceram. Soc. v.39 no.7 Fracture behavior of Silicon Nitride-Silicon Carbide-Boron Nitride Multi-Layer Composites with Different Layer Thickness B.U.Cho;D.S.Park;H.C.Park https://doi.org/10.4191/KCERS.2002.39.7.622
  4. Progress in Nitrogen Ceramics R.N.Katz
  5. J. Mat. Sci. v.14 Review : Reaction-Bonded Silicon Nitride ; It's Formation Properties A.J.Moulson https://doi.org/10.1007/BF00561289
  6. J. Eur. Ceram. Soc. v.21 Effect of Nitrogen Pressure and Oxygen-Containing Impurities on Self-Propagating High Temperature Synthesis of Si₃N₄ H.Wang https://doi.org/10.1016/S0955-2219(00)00189-8
  7. J. Am. Ceram. Soc. v.84 no.8 Catalytic Effects of Metals on Direct Nitridation of Silicon V.Pavarajarn;S.Kimura https://doi.org/10.1111/j.1151-2916.2001.tb00897.x
  8. Ceram. Eng. Sci. Proc. v.18 no.4 Effects of Pre-Existed Silicon Nitride in the Direct Nitridation Process of Liquid Silicon T.S.Sheu https://doi.org/10.1002/9780470294444.ch72
  9. J. Mat. Sci. v.34 no.4 Production of Si₃N₄ by Carbothermal Reduction and Nitridation of Sepiolite H.Arik;S.Saritas;M.Gunduz https://doi.org/10.1023/A:1004541401063
  10. J. of Mat. Sci. v.36 no.24 Synthesis of Si₃N₄ Using Sepiolite and various Sources of Carbon A.O.Kurt;T.J.Davis https://doi.org/10.1023/A:1012980711023
  11. J. of Mat. Sci. v.31 no.22 Chemical Vapour Deposition of Silicon Nitride in a Microwave Plasma Assisted Reactor Z.Wang;I.G.Brown https://doi.org/10.1007/BF01152155
  12. Chemistry of Solid State Materials : Chemical Synthesis of Advanced Ceramic Materials S.David
  13. Russ. Chem. Bull. v.46 no.1 Reviews : Fundamentals, Achievements, and Perspectives for Development of Solid-Flame Combustion A.G.Merahanov
  14. Self Propaating High Temperature Synthesis : Twenty Years of Research and Findings A.G.Merzhanov
  15. Ceram. Bull. v.68 no.6 Soviet SHS Technology : A potential U.S. Advantage in Ceramics J.Kiser;R.M.Spriggs
  16. J. Kor. Ceram. Soc. v.40 no.1 Preparation of B₄CAl₂O₃Composite Powder by Self-Propagation High-Temperature Synthesis(SHS) Process under High Pressure K.R.Han;D.I.Kang;C.S.Kim https://doi.org/10.4191/KCERS.2003.40.1.018
  17. J. Kor. Ceram. Soc. v.30 no.12 A Study on the Synthesis of Titanium Nitride by SHS(Self-Propagating High-Temperature Synthesis) Method K.R.Kim;H.C.Lee;H.Ha
  18. Int. J. SHS. v.9 no.2 Some Regularities of α-Si₃N₄Synthesis in a Commercial SHS Reastor V.V.Zakorzhevskii;I.P.Borovinskaya
  19. Adv. Ceram. Mater. v.2 no.4 Combustion Reaction Characteristics in the Nitridation of Silicon K.Hirao;Y.Miyamoto;M.Koizumi
  20. Int. J. SHS v.5 no.2 On the Mechanism of Self-Propagating High Temperature Synthesis of Si₃N₄ C.C.Ge;J.T.Li;Y.L.Xia
  21. J. Crys. Growth v.234 Formation of α-Si₃N₄Whiskers with addition of NaN₃as Catalyst Y.G.Cao;H.Chen;J.T.Li;C.C.Ge;S.Y.Tang;J.X.Tang https://doi.org/10.1016/S0022-0248(01)01690-6