Hostname: page-component-7479d7b7d-767nl Total loading time: 0 Render date: 2024-07-08T18:24:59.878Z Has data issue: false hasContentIssue false

Tensile Creep Behavior in Lutetia-doped Silicon Nitride Ceramics

Published online by Cambridge University Press:  01 August 2005

Toshiyuki Nishimura*
Affiliation:
National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
Naoto Hirosaki
Affiliation:
National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
Yoshinobu Yamamoto
Affiliation:
National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
Yorinobu Takigawa
Affiliation:
Japan Fine Ceramics Center, Nagoya, Aichi 456-8587, Japan
Jian-Wu Cao
Affiliation:
Japan Fine Ceramics Center, Nagoya, Aichi 456-8587, Japan
*
a) Address all correspondence to this author. e-mail: NISHIMURA.Toshiyuki@nims.go.jp
Get access

Abstract

We studied tensile creep behavior in two silicon nitride ceramics, i.e., 4.8 mol% Lu2O3 (SN48) and 1.2 mol% Lu2O3 (SN12), at 1400–1500 °C under applied stress of 137–300 MPa. Time to failure of SN48 increased with decreasing applied stress and minimum strain rate. The stress–rupture parameter was 10.7 at 1400 °C and 11.4 at 1500 °C. Pore formation was confirmed in a creep-tested specimen of SN48 by transmission electron microscopy. These results suggest that SN48 was fractured by creep rupture. The minimum strain rate of SN12 was almost below the measurement system limitation at temperatures below 1500 °C. Time to failure tended to increase with decreasing applied stress. The stress–rupture parameter was 41 at 1400 °C and 73 at 1500 °C. These results suggest that SN12 was fractured by subcritical crack growth.

Type
Articles
Copyright
Copyright © Materials Research Society 2005

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

1Nishimura, T. and Mitomo, M.: Phase relationships in the system Si3N4–SiO2–Yb2O3. J. Mater. Res. 10, 240 (1995).CrossRefGoogle Scholar
2Nishimura, T., Mitomo, M. and Suematsu, H.: High temperature strength of silicon nitride ceramics with ytterbium silicon oxynitride. J. Mater. Res. 12, 203 (1997).CrossRefGoogle Scholar
3Guo, S., Hirosaki, N., Nishimura, T., Yamamoto, Y. and Mitomo, M.: Oxidation behaviour and strength degradation of a Yb2O3–SiO2-doped hot-pressed silicon nitride between 1200 and 1500 °C. Philos. Mag. A 82, 3027 (2002).Google Scholar
4Cao, J., Okada, A. and Hirosaki, N.: Tensile creep behavior of an ytterbium silicon oxynitride-silicon nitride ceramic. J. Eur. Ceram. Soc. 22, 769 (2002).CrossRefGoogle Scholar
5And, C.A.ersson and Barton, R.: Final Technical Report, U.S. Energy Res. Dev. Adm. Contact No. EY-76-C-05-5210 (1977).Google Scholar
6Shannon, R.D.: Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr. A 32, 751 (1976).CrossRefGoogle Scholar
7Hirosaki, N., Yamamoto, Y., Nishimura, T., Mitomo, M., Takahashi, J., Yamane, H. and Shimada, M.: Phase relationships in the Si3N4–SiO2–Lu2O3 system. J. Am. Ceram. Soc. 85, 2861 (2002).CrossRefGoogle Scholar
8Morgan, P.E.D., Lange, F.F., Clarke, D.R. and Davis, B.I.: A new Si3N4 material: Phase relations in the system Si–Sc–O–N and preliminary property studies. J. Am. Ceram. Soc. 64, C-77 (1981).CrossRefGoogle Scholar
9Cao, J., Okada, A. and Hirosaki, N.: Creep and stress-rupture behavior of Y2O3–Nd2O3-doped silicon nitrides with different additive contents. J. Euro. Ceram. Soc. 22, 237 (2002).CrossRefGoogle Scholar
10Guo, S., Hirosaki, N., Yamamoto, Y., Nishimura, T. and Mitomo, M.: Improvement of high-temperature strength of hot-pressed sintering silicon nitride with Lu2O3 addition. Scripta Mater. 45, 867 (2001).CrossRefGoogle Scholar
11Guo, S., Hirosaki, N., Yamamoto, Y., Nishimura, T., Kitami, Y. and Mitomo, M.: Microstructural characterization and high-temperature strength of hot-pressed silicon nitride ceramics. Philos. Mag. Let. 83, 357 (2003).CrossRefGoogle Scholar
12Guo, S., Hirosaki, N., Yamamoto, Y., Nishimura, T. and Mitomo, M.: Hot-pressed silicon nitride with Lu2O3 additives: Oxidation and its effect on strength. J. Am. Ceram. Soc. 86, 1900 (2003).CrossRefGoogle Scholar
13Guo, S., Hirosaki, N., Yamamoto, Y., Nishimura, T. and Mitomo, M.: Strength retention in hot-pressed Si3N4 ceramics with Lu2O3 additives after oxidation exposure in air at 1500 °C. J. Am. Ceram. Soc. 85, 1607 (2002).CrossRefGoogle Scholar
14Lofaj, F., Wiederhorn, S.M., Long, G.G., Hockey, B.J., Jemian, P.R., Browder, L., Andreason, J. and Täffner, U.: Non-cavitation tensile creep in Lu-doped silicon nitride. J. Euro. Ceram. Soc. 22, 2479 (2002).CrossRefGoogle Scholar
15Yamamoto, Y., Nishimura, T., Hirosaki, N., Guo, S., Cao, J., and Mitomo, M.: High-temperature properties of silicon nitride with Lu–Si–O–N grain boundary phases. (Submitted to Key Engineering Materials).Google Scholar