27. The Effects of Incorporating System Level Variability Into the Reliability Analysis for Ceramic Components

  1. Manuel E. Brito,
  2. Peter Filip,
  3. Charles Lewinsohn,
  4. Ali Sayir,
  5. Mark Opeka and
  6. William M. Mullins
  1. Robert Carter1 and
  2. Osama Jadaan2

Published Online: 26 MAR 2008

DOI: 10.1002/9780470291283.ch27

Developments in Advanced Ceramics and Composites: Ceramic Engineering and Science Proceedings, Volume 26, Number 8

Developments in Advanced Ceramics and Composites: Ceramic Engineering and Science Proceedings, Volume 26, Number 8

How to Cite

Carter, R. and Jadaan, O. (2005) The Effects of Incorporating System Level Variability Into the Reliability Analysis for Ceramic Components, in Developments in Advanced Ceramics and Composites: Ceramic Engineering and Science Proceedings, Volume 26, Number 8 (eds M. E. Brito, P. Filip, C. Lewinsohn, A. Sayir, M. Opeka and W. M. Mullins), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470291283.ch27

Author Information

  1. 1

    Ordnance Materials Branch, Materials Division Army Research Laboratory Aberdeen Proving Ground, MD 21005

  2. 2

    University of Wisconsin-Platteville College of Engineering, Mathematics and Science Platteville, WI 53818

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2005

ISBN Information

Print ISBN: 9781574982619

Online ISBN: 9780470291283

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Keywords:

  • components;
  • parameter;
  • materials;
  • geometric;
  • stochastic

Summary

Probabilistic failure analyses evaluate the effects of strength variability in brittle materials on the design of ceramic components. However, strength is not the only stochastic parameter in ceramic components and making such an assumption can result in failed designs. Other variable parameters such as geometry, fabrication, materials, and service load histories should also be considered when evaluating the total probability of failure for the component. Slight variations in these variables can alter the stress distribution within the ceramic, and change the probabilities of failure for the system. This effort demonstrates an approach for incorporating the statistical scatter in material properties and system conditions, as well as the Weibull properties of the ceramic in the probability of failure calculations. The evaluated system is an internally pressurized ceramic tube with a steel sheath that imparts a pre-stress through a shrink-fit operation. Two analyses have been performed where the initial analysis is deterministic in nature, in that there is no variability in the inputs to the Weibull analysis. The first analysis calculates the optimal geometry and pre-stress levels for the lowest probability of failure. The second analysis was performed using ANSYS PDS (Probabilistic Design System) and CARES/Life software to evaluate the total probability of failure for a more realistic system with variability in the different material properties, Weibull parameters, pre-stress levels, pressure loading, and geometric inputs. The results of the PDS analysis illustrate that the probability of failure is not a single value, as defined by the first analysis, but a range spanning several orders of magnitude.