Chapter 13. Alumna-Based Functionally Gradient Materials by Centrifugal Molding Technology

  1. Edgar Lara-Curzio and
  2. Michael J. Readey
  1. Chun-Hong Chen,
  2. Tadahiro Nishikawa,
  3. Sawao Honda and
  4. Hideo Awaji Nagoya

Published Online: 26 MAR 2008

DOI: 10.1002/9780470291184.ch13

28th International Conference on Advanced Ceramics and Composites A: Ceramic Engineering and Science Proceedings, Volume 25, Issue 3

28th International Conference on Advanced Ceramics and Composites A: Ceramic Engineering and Science Proceedings, Volume 25, Issue 3

How to Cite

Chen, C.-H., Nishikawa, T., Honda, S. and Nagoya, H. A. (2004) Alumna-Based Functionally Gradient Materials by Centrifugal Molding Technology, in 28th International Conference on Advanced Ceramics and Composites A: Ceramic Engineering and Science Proceedings, Volume 25, Issue 3 (eds E. Lara-Curzio and M. J. Readey), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470291184.ch13

Author Information

  1. Institute of Technology, Nagoya, Japan, 466 8555

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2004

ISBN Information

Print ISBN: 9780470051498

Online ISBN: 9780470291184

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Keywords:

  • FGMS;
  • CMT;
  • EDX;
  • XRD;
  • ABT

Summary

Ceramic-based functionally gradient materials (FGMs) were fabricated by centrifugal molding technique (CMT). Experiments were performed with colloidally processed suhmicron alumina powders and two kinds of tungsten powders (10vol.%). the powder mix was made into slurry by adding alcohol and hollow cylinders were cast using a stainless steel mold. A drying procedure was carried out after casting in a partial vacuum atmosphere to avoid cracks. Tungsten profiles were measured by microstructure observations and EDX analysis. Vickers hardness distributions also proved the compositional variation from inner to outer surface of the gradient cylinders. the result showed that the control of the composite formability has great influence on the composition gradient along the radial direction, which can be attained by varying the ratio of the fine to coarse powders. the slurry viscosity ranging from 100mPas to 300mPas was found to be suitable for the continuous gradient of hollow cylinders. Residual thermal stresses generated during the cooling process were also analyzed. the hoop residual stresses distributed from tensile on the inner surface to compressive on the outer surface due to the gradual material properties of the alumina-tungsten FGM cylinder. the results obtained indicate that stress concentrations at the interface can be relaxed by the continuous variation of the material properties.