Bulk Consolidation of Non-Oxide Ceramic Powders Derived from Polymer Precursors

Abstract:

Consolidation of pyrolyzed powders has been tried by hot isostatic pressing (HIP) without sintering additives, in order to obtain dense non-oxide ceramic bulk materials derived from polymer precursors. Si1.0C1.6N1.3 ceramic powders were derived from a polyvinylsilazane polymer. The polymer was thermally crosslinked at 250oC and pyrolyzed at 1050oC under Ar atmosphere. The pyrolyzed powders were die-pressed into rectangular bars at room temperature and densified by HIP at 1400oC-900 MPa and 1500oC-950 MPa. Dense ceramic monolith, in which pores were not observed by optical microscopy, was obtained by the HIP consolidation at 1500oC-950 MPa. The microstructure of the ceramic monolith was a nano-composite structure consisted of α-Si3N4 and graphite phases. In the compression tests of the HIP-treated sample, slight plastic deformation was observed at 1400 and 1500oC in spite of high compressive stress over 1000 MPa. On the other hand, the sample showed a compressive strain of about 7% at 1000 MPa at 1600oC. The compressive strain of about 11% was achieved at 1700oC.

• Periodical: Key Engineering Materials (Volumes 317-318)
• Pages: 15-18
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.317-318.15
• Online since: August 2006
• Authors: Satoru Ishihara, Toshiyuki Nishimura, Joachim Bill, Fritz Aldinger, Fumihiro Wakai
• Keywords: Amorphous, Hot Isostatic Pressing (HIP), Porosity, Precursor Derived Ceramics, SiCN

References

[1] S. Yajima, J. Hayashi and M. Omori: Chem. Lett. (1975), p.931.

[2] R. Riedel, G. Passing, H. Schoenfelder and R. J. Brook: Nature Vol. 355 (1992), p.714.

[3] J. Bill and F. Aldinger: Adv. Mater. Vol. 7 (1995), p.775.

[4] J. Bill and F. Aldinger: Z. Metallkd. Vol. 87 (1996), p.827.

[5] S. Yajima: J. Am. Ceram. Soc. Vol. 52 (1976), p.324.

[6] J. Seitz and J. Bill: J. Mat. Sci. Let. Vol. 15 (1996), p.391.

[7] R. Haug, M. Weinmann, J. Bill and F. Aldinger: J. Europ. Ceram. Soc. Vol. 19 (1999), p.1.

[8] J. Seitz, J. Bill, N. Egger and F. Aldinger: J. Europ. Ceram. Soc. Vol. 16 (1996), p.885.

[9] G. Thurn and F. Aldinger: Precursor-Derived Ceramics (Wiley-VCH Publishers, Weinheim 1999) p.237.

[10] L. An, R. Riedel, C. Konetschny, H. -J. Kleebe and R. Raj: J. Am. Ceram. Soc. Vol. 81 (1998), p.1349.

[11] R. Riedel, L. M. Ruswisch, L. An and R. Raj: J. Am. Ceram. Soc. Vol. 81 (1998), p.3341.

[12] B. Baufeld, H. Gu, J. Bill, F. Wakai and F. Aldinger: J. Europ. Ceram. Soc. Vol. 19 (1999), p.2797.

[13] N. Kondo, F. Wakai, M. Yamagiwa, T. Nishioka, and A. Yamakawa: Mater. Sci. and Eng. Vol. A206 (1996), p.45.

[14] G. D. Zhan, M. Mitomo, T. Nishimura, R. J. Xie, T. Sakuma, and Y. Ikuhara: J. Am. Ceram. Soc. Vol. 83 (2000), p.841.