Chapter 50. Transparent MgAl2O4 Spinel — Revisited

  1. Todd Jessen and
  2. Ersan Ustundag
  1. Mark C. L. Patterson1,
  2. Jenni E. Caiazza1,
  3. Don W. Roy2 and
  4. Gary Gilde3

Published Online: 28 MAR 2008

DOI: 10.1002/9780470294635.ch50

24th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B: Ceramic Engineering and Science Proceedings, Volume 21, Issue 4

24th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B: Ceramic Engineering and Science Proceedings, Volume 21, Issue 4

How to Cite

Patterson, M. C. L., Caiazza, J. E., Roy, D. W. and Gilde, G. (2008) Transparent MgAl2O4 Spinel — Revisited, in 24th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B: Ceramic Engineering and Science Proceedings, Volume 21, Issue 4 (eds T. Jessen and E. Ustundag), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470294635.ch50

Author Information

  1. 1

    Ceramic Composites Inc., 1110 Benfield Boulevard Millersville, Maryland 21108 USA

  2. 2

    10644 West Dumbarton Circle, Unit C Littleton, Colorado, 80127 USA

  3. 3

    U.S. Army Research Laboratory AMSFU-WM-MC Building 4600 Aberdeen Proving Grounds Aberdeen, Maryland, 21005 USA

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 2000

ISBN Information

Print ISBN: 9780470375693

Online ISBN: 9780470294635

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Keywords:

  • aluminum oxynitride;
  • technology assessment and transfer;
  • alpha optical systems;
  • HIP technology;
  • rate controlled sintering

Summary

Magnesium aluminate spinel (MgAl,2O4), aluminum oxynitride (ALON) and sapphire (Al2O3) have been well documented in the past for a range of applications (armor, domes and windows) requiring transparency in the 0.3μm to 5.5μm range. Over the past thirty years the need for improved, light-weight transparent armor systems, and IR domes and windows with low erosion rates, has supported the development of these materials to their present capability. Preliminary tests suggest that the ballistic properties of spinel are similar to ALON and sapphire, and that the transmission properties at 4.5μm and beyond are better, particularly as temperature increases. Although qualified for several window and dome applications there is presently no commercial supplier of spinel. A Cooperative Research and Development Agreement between the U.S. Army Research Laboratory (ARL) and the Advanced Ceramic Development Group of Technology Assessment and Transfer, (TA&T) is presently underway to fabricate large transparent spinel armor plates, thus establishing TA&T as a commercial supplier. In the fbture TA&T will also pursue the fabrication of domes up to 8” in diameter. This paper describes the achievements to date which have focused on extending existing process capabilities and establishing optimal processing parameters for powder processing and hot-pressing, followed by HIPing.