Articles
All articles | Recent articles
SiC/BN Composites by Spark Plasma Sintering (SPS) of Precursor-Derived SiBNC Powders
J. Wilfert1, K. Meier2, K. Hahn3, Y. Grin2, M. Jansen1
1 Max-Planck-Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
2 Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
3 Stuttgart Center for Electron Microscopy, Max-Planck-Institute for Metals Research, Heisenbergstr. 3, 70569 Stuttgart, Germany
received April 14, 2010, received in revised form April 26, 2010, accepted July 26, 2010
Vol. 1, No. 1, Pages 1-6 DOI: 10.4416/JCST2010-00012
Abstract
Preceramic polyborocarbosilazane was pyrolysed at 900 °C and 1400 °C, respectively, yielding amorphous SiBNC. The as-obtained powders were subsequently spark plasma sintered (SPS) at temperatures in a range between 1400 °C and 1800 °C for 10 minutes under uniaxial pressure of 50 MPa. The samples have been characterized by SEM, TEM, XRD, helium pycnometry and Vickers hardness measurements. Independent of the pyrolysis temperature of the starting materials, the most compact samples were obtained by SPS at 1800 °C. In SPS conditions the onset of crystallization and phase separation of the amorphous SiBNC ceramic is substantially reduced as compared to conventional heating. A composite microstructure is obtained, which consists of SiC crystallites with diameters smaller than 500 nm, embedded in a matrix of turbostratic BN. Hardness values increase to 3 GPa when the SPS temperature is raised. TGA in O2 shows a high resistance against oxidation of the SPS compacts.
Download Full Article (PDF)
Keywords
Precursor-derived ceramics, composites, microstructure analysis, SiC, Spark plasma sintering
References
1 Baldus, H.-P., Wagner, O., Jansen, M., Synthesis of advanced ceramics in the systems Si-B-N and Si-B-N-C employing novel precursor compounds, Mat. Res. Soc. Symp. Proc., 271, 821-826, (1992).
2 Baldus, H.-P., Jansen, M., Sporn, D., Ceramic fibers for matrix composites in high-temperature engine applications, Science, 285, 699-703, (1999).
3 Baldus, H.-P., Jansen, M., Moderne Hochleistungskeramiken – amorphe anorganische Netzwerke aus molekularen Vorläufern (Modern high-performance ceramics – amorphous networks from molecular precursors), Angew. Chem., 109, 338-354, (1997).
4 Jansen, M., Jäschke, B., Jäschke, T., Amorphous Multinary Ceramics in the Si-B-N-C System, Struct. Bonding, 101, 137-191, (2002).
5 Baldus, H.-P., Jansen, M., Wagner. O., New materials in the system Si-(N,C)-B and their characterization, Key Eng. Mater., 89-91, 75-80, (1994).
6 Jäschke, T., Jansen, M., A new borazine-type single source precursor for Si/B/N/C ceramics, J. Mater. Chem., 16, 2792-2799, (2008).
7 Riedel, R., Kienzle, A., Dressler, W., Ruwisch, L., Bill, J., Aldinger, F., A silicoboron carbonitride ceramic stable to 2000 °C, Nature, 382, 796-798, (1996).
8 Müller, U., Weinmann, M., Jansen, M., Cl2MeSi-NH-BCl2 and ClMe2Si-NH-BCl2: novel processable single source precursors of amorphous Si/C/B/N ceramics, J. Mater. Chem., 18, 3671-3697, (2008).
9 Sehlleier, Y. H., Verhoeven, A., Jansen, M., Observation of direct bonds between carbon and nitrogen in Si-B-N-C ceramic after pyrolysis at 1400 °C, Angew. Chem. Int. Ed., 47, 3600-3602, (2008).
10 Jansen, M., Kroschel, M., Conversion of M-Methylpolyborosilazane to Amorphous Siliconboroncarbonitride, Z. Anorg. Allg. Chem., 626, 1634-1638, (2000).
11 Baldus, H.-P., Passing, G., Scholz, H., Sporn, D., Jansen, M., Göring, J., Properties of amorphous SiBNC-ceramic fibers, Key Eng. Mater., 127-131, 177-184, (1997).
12 Sinclair, W., Simmons, H., Microstructure and thermal shock behaviour of BN composites, J. Mat. Sci. Lett., 6, 627-629, (1987).
13 Funahashi, T., Isomura, K., Harita, A., Uchimura, R., Mechanical properties and microstructure of Si3N4-BN composite ceramics. In: Ceramic materials and components for engines. ed. Tennery, V. J., Westerville (OH), Am. Cer. Soc., p. 968-976, (1989).
14 Kusunose, T., Sekino, T., Choa, Y.-H., Niihara, K., Machinability of silicon nitride/boron nitride nanocomposites, J. Am. Ceram. Soc., 85, 2689-2695, (2002).
15 Ruh, R., Bentsen, L. D., Hasselman, D. P. H., Thermal Diffusivity Anisotropy of SiC/BN Composties, J. Am. Ceram. Soc., 67, C-83-C-84, (1984).
16 Zhang, G.-J., Ohji, T., Characterization of in situ SiC-BN composites. In: Ceramic Materials and Components for Engines. eds. Heinrich, J. G., Aldinger, F., Weinheim, Wiley-VCH, 471-476 (2001).
17 Millot, N., Le Gallet, S., Aymes, D., Bernard, F., Grin, Y., Spark plasma sintering of cobalt ferrite nanopowders prepared by coprecipitation and hydrothermal synthesis, J. Eur. Ceram. Soc., 27, 921-926, (2007).
18 Bai, L., Mao, X., Shen, W., Ge, C., Comparative study of b-Si3N4 powders prepared by SHS sintered by spark plasma sintering and hot pressing, J. Univ. Technol. Beijing, 14, 271-275, (2002).
19 Jin, H. Y., Ishiyama, M., Qiao, G.-J., Gao, J.-Q., Jin, Z.-H., Plasma active sintering of silicon carbide, Mater. Sci. Eng. A, 483-484, 270-273, (2008).
20 Tamari, N., Tanaka, T., Tanaka, K., Kondoh, I., Kawahara, M., Tokita, M., Effect of Spark Plasma Sintering on Densification and Mechanical Properties of Silicon Carbide, J. Ceram. Soc. Japan, 103, 740-742, (1995).
21 Schmidt, J., Anwendung des Spark Plasma Sinterverfahrens für Präparationszwecke in der Festkörperchemie (Application of Spark Plasma Sintering for Preparation Purposes in Solid-State Chemistry). Dissertation, Technische Universität Dresden (2003).
22 Buresch, O., von Schnering, H. G., Ein neuer Teflon-Einsatz zum Säureaufschluss kleiner Proben im Druckaufschluss-System Berghof - DA I (A New Teflon Liner for Acid Digestion of Small Samples in the Pressure Digestion System Berghof – DA I), Fresenius Z. Anal. Chem., 319, 418-420, (1984).
23 Thomas, J., Weston, N. E., O'Connor, T. E., Turbostratic Boron Nitride, Thermal Transformation to Ordered-layer-lattice Boron Nitride, J. Am. Chem. Soc., 84, 4619-4622, (1963).
24 Schwetz, K. A., Silicon carbide based hard materials. In: Handbook of ceramic hard materials. ed. Riedel, R., Weinheim, Wiley-VCH Verlag GmbH, 683-748 (2000).
25 Holleman, A. F., Wiberg, E., Wiberg, N., Lehrbuch der anorganischen Chemie (Textbook of Inorganic Chemistry). 102nd edition. Berlin, Walter de Gruyter, (2007).
26 Kumar, R., Cai, Y., Gerstel, P., Rixecker, G., Aldinger, F., Processing, crystallization and characterization of polymer derived nano-crystalline Si-B-C-N ceramics, J. Mater. Sci., 41, 7088-7095, (2006).
Copyright
© 2010 Göller Verlag
Acknowledgments
We thank U. Salzberger for the technical support with the TEM sample preparation, M.-L. Schreiber for the chemical analysis and C. Eberl for the density measurements.
