Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-28T00:50:48.077Z Has data issue: false hasContentIssue false
  • English
  • Français

Influence of additive composition on thermal and mechanical properties of β–Si3N4 ceramics

Published online by Cambridge University Press:  01 November 2004

Xinwen Zhu ,
Hiroyuki Hayashi ,
You Zhou  and
Kiyoshi Hirao
Xinwen Zhu
Affiliation:
Advanced Manufacturing Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560, Japan
Hiroyuki Hayashi
Affiliation:
Toyota Technological Institute, Nagoya 468-8511, Japan
You Zhou
Affiliation:
Advanced Manufacturing Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560, Japan
Kiyoshi Hirao*
Affiliation:
Advanced Manufacturing Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560, Japan
*
a)Address all correspondence to this author.e-mail: k-hirao@aist.go.jp
Get access

Abstract

Dense β–Si3N4 ceramics were fabricated from α–Si3N4 raw powder by gas-pressure sintering at 1900 °C for 12 h under a nitrogen pressure of 1 MPa, using four different kinds of additive compositions: Yb2O3–MgO, Yb2O3–MgSiN2, Y2O3–MgO, and Y2O3–MgSiN2. The effects of additive composition on the microstructure and thermal and mechanical properties of β–Si3N4 ceramics were investigated. It was found that the replacement of Yb2O3 by Y2O3 has no significant effect on the thermal conductivity and fracture toughness, but the replacement of MgO by MgSiN2 leads to an increase in thermal conductivity from 97 to 113 Wm-1K-1and fracture toughness from 8 to 10 MPa m1/2, respectively. The enhanced thermal conductivity of the MgSiN2-doped materials is attributed to the purification of β–Si3N4 grain and increase of Si3N4–Si3N4 contiguity, resulting from the enhanced growth of large elongated grains. The improved fracture toughness of the MgSiN2-doped materials is attributed to the increase of grain size and fraction of large elongated grains. However, the same thermal conductivity between the Yb2O3- and Y2O3-doped materials is related to not only their similar microstructures, but also the similar abilities of removing oxygen impurity in Si3N4 lattice between Yb2O3 and Y2O3. The same fracture toughness between the Yb2O3- and Y2O3-doped materials is consistent with their similar microstructures. This work implies that MgSiN2 is an effective sintering aid for developing not only high thermal conductivity (>110 Wm−1K−1) but also high fracture toughness (>10 MPa m1/2) of Si3N4 ceramics.

Keywords

CeramicThermal conductivityMechanical properties
Type
Articles
Information
Journal of Materials Research , Volume 19 , Issue 11 , November 2004 , pp. 3270 - 3278
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Hirao, K., Watari, K., Brito, M.E., Toriyama, M. and Kanzaki, S.: High thermal conductivity in silicon nitride with anisotropic microstructure. J. Am. Ceram. Soc. 79, 2485 (1996).CrossRefGoogle Scholar
2Okamoto, Y., Hirosaki, N., Ando, M., Munakata, F. and Akimune, Y.: Effect of sintering additive composition on the thermal conductivity of silicon nitride. J. Mater. Res. 13, 3473 (1998).CrossRefGoogle Scholar
3Watari, K., Hirao, K., Brito, M.E., Toriyama, M. and Kanzaki, S.: Hot isostatic pressing to increase thermal conductivity of Si3N4 ceramics. J. Mater. Res. 14, 1538 (1999).CrossRefGoogle Scholar
4Hayashi, H., Hirao, K., Toriyama, M., Kanzaki, S. and Itatani, K.: MgSiN2 addition as a means of increasing the thermal conductivity of β–silicon nitride. J. Am. Ceram. Soc. 84, 3060 (2001).CrossRefGoogle Scholar
5Kitayama, M., Hirao, K., Watari, K., Toriyama, M. and Kanzaki, S.: Thermal conductivity of β–Si3N4: III, Effect of rare-earth (RE = La, Nd, Gd, Y, Yb, and Sc) oxide additives. J. Am. Ceram. Soc. 84, 353 (2001).CrossRefGoogle Scholar
6Yokota, H., Abe, H. and Ibukiyama, M.: Effect of lattice defects on the thermal conductivity of β- Si3N4. J. Eur. Ceram. Soc. 23, 1751 (2003).CrossRefGoogle Scholar
7Yokota, H. and Ibukiyama, M.: Effect of the addition of β–Si3N4 nuclei on the thermal conductivity of β- Si3N4 ceramics. J. Eur. Ceram. Soc. 23, 1183 (2003).CrossRefGoogle Scholar
8Virkar, A.V., Jackson, T.B. and Cutler, R.A.: Thermodynamic and kinetic effects of oxygen removal on the thermal conductivity of aluminum nitride. J. Am. Ceram. Soc. 72, 2031 (1989).CrossRefGoogle Scholar
9Jackson, T.B., Virkar, A.V., More, K.L., Dinwiddie, R.B.Jr., and Cutler, R.A.: High-thermal-conductivity aluminum nitride ceramics: The effect of thermodynamic, kinetic, and microstructural factors. J. Am. Ceram. Soc. 80, 1421 (1997).CrossRefGoogle Scholar
10Kitayama, M., Hirao, K., Tsuge, A., Watari, K., Toriyama, M. and Kanzaki, S.: Thermal conductivity of β–Si3N4: II. Effect of lattice oxygen. J. Am. Ceram. Soc. 83, 1985 (2000).CrossRefGoogle Scholar
11Hayashi, H., Hirao, K., Kitayama, M., Kanzaki, S. and Itatani, K.: Effect of oxygen content on thermal conductivity of sintered silicon nitride. J. Ceram. Soc. Jpn. 109, 1046 (2001).CrossRefGoogle Scholar
12Hirao, K., Watari, K., Hayashi, H. and Kitayama, M.: High thermal conductivity silicon nitride. MRS Bull. 26, 451 (2001).CrossRefGoogle Scholar
13Kitayama, M., Hirao, K., Toriyama, M. and Kanzaki, S.: Thermal conductivity of β–Si3N4: I, Effects of various microstructural factors. J. Am. Ceram. Soc. 82, 3105 (1999).CrossRefGoogle Scholar
14Yokota, H., Yamada, S. and Ibukiyama, M.: Effect of large β–Si3N4 particles on the thermal conductivity of β–Si3N4 ceramics. J. Eur. Ceram. Soc. 23, 1175 (2003).CrossRefGoogle Scholar
15Pablos, A.D., Osendi, M.I. and Miranzo, P.: Effect of microstructure on the thermal conductivity of hot-pressed silicon nitride materials. J. Am. Ceram. Soc. 85, 200 (2002).CrossRefGoogle Scholar
16Hirosaki, N., Okamoto, Y., Ando, M., Munakata, F. and Akimune, Y.: Thermal conductivity of gas-pressure–Sintered silicon nitride. J. Am. Ceram. Soc. 79, 2878 (1996).CrossRefGoogle Scholar
17Ye, J., Kojima, N., Furuya, K., Munakata, F. and Okada, A.: Micro-thermal analysis of thermal conductance distribution in advanced silicon nitrides. J. Therm. Anal. Calorim. 69, 1031 (2002).CrossRefGoogle Scholar
18Lenčéš, Z., Hirao, K., Yamauchi, Y. and Kanzaki, S.: Reaction synthesis of magnesium silicon nitride powder. J. Am. Ceram. Soc. 86, 1088 (2003).CrossRefGoogle Scholar
19Nose, T. and Fujii, T.: Evaluation of fracture toughness for ceramic materials by a single-edge-precracked-beam method. J. Am. Ceram. Soc. 71, 328 (1988).CrossRefGoogle Scholar
20Greskovich, C. and Prochazka, S.: Stability of Si3N4 and liquid phase(s) during sintering. J. Am. Ceram. Soc. 64, C-96 (1981).CrossRefGoogle Scholar
21Lang, F.F.: Volatilization associated with the sintering of polyphase Si3N4 materials. J. Am. Ceram. Soc. 65, C-120 (1982).Google Scholar
22Baik, S. and Raj, R.: Effect of silicon activity on liquid-phase sintering of nitrogen ceramics. J. Am. Ceram. Soc. 68, C-124 (1985).CrossRefGoogle Scholar
23Kim, W.J., Kim, D.Y. and Kim, C.H.: Morphological effect of second phase on the thermal conductivity of AlN ceramics. J. Am. Ceram. Soc. 79, 1066 (1996).CrossRefGoogle Scholar
24Boey, F., Tok, A.I.Y., Lam, Y.C. and Chew, S.Y.: On the effects of secondary phase on thermal conductivity of AlN ceramic substrates using a microstructural modelling approach. Mater. Sci. Eng. A 335, 281 (2002).CrossRefGoogle Scholar
25Dressler, W., Kleebe, H.J., Hoffmann, M.J., Rühle, M. and Petzow, G.: Model experiments concerning abnormal grain growth in silicon nitride. J. Eur. Ceram. Soc. 16, 3 (1996).CrossRefGoogle Scholar
26Björklund, H., Falk, L.K.L., Rundgren, K. and Wasén, J.: β–Si3N4 grain growth, Part I: Effect of metal oxide sintering additives. J. Eur. Ceram. Soc. 17, 1285 (1997).CrossRefGoogle Scholar
27Kleebe, H.J., Pezzotti, G. and Ziegler, G.: Microstructure and fracture toughness of Si3N4 ceramics: Combined roles of grain morphology and secondary phase chemistry. J. Am. Ceram. Soc. 82, 1857 (1999).CrossRefGoogle Scholar
28Ramesh, R., Nestor, E., Pomeroy, M.J. and Hampshire, S.: Formation of Ln-Si-Al-O-N glasses and their properties. J. Eur. Ceram. Soc. 17, 1933 (1997).CrossRefGoogle Scholar
29Faber, K.T. and Evans, A.G.: Crack deflection processes: Theory and experiment. Acta Metall. 31, 565 (1983).CrossRefGoogle Scholar
30Becher, P.F.: Microstructural design of toughened ceramics. J. Am. Ceram. Soc. 74, 255 (1991).CrossRefGoogle Scholar
31Park, H.J., Kim, H.E. and Niihara, K.: Microstructural evolution and mechanical properties of Si3N4 with Yb2O3 as a sintering additive. J. Am. Ceram. Soc. 80, 750 (1997).CrossRefGoogle Scholar
32Hoffman, M.J. in Tailoring of Mechanical Properties of Si3N4 Ceramics, edited by Hoffmann, M.J. and Petzow, G. (NATO ASI Series E: Applied Sciences, Vol. 276 Kluwer Academic Publishers, Dordrecht, The Netherlands, 1993), pp. 233–244.Google Scholar