0
RESEARCH PAPERS: Gas Turbines: Ceramics

Long-Term Testing of Advanced Ceramics: Concerns, Insights, and Recommendations

[+] Author and Article Information
M. G. Jenkins

Department of Mechanical Engineering, University of Washington, Seattle, WA 98195

J. Eng. Gas Turbines Power 118(4), 704-710 (Oct 01, 1996) (7 pages) doi:10.1115/1.2816983 History: Received February 27, 1995; Online November 19, 2007

Abstract

Advanced ceramics have reached a level of material development to warrant serious consideration for use in advanced heat engine designs. Typically, design requirements based on service conditions may include 25,000 h lifetimes under stresses and temperatures of up to 250 MPa and 1370°C, respectively, with probabilities of failure of <0.1 percent. To assure that materials meet these stringent requirements requires long-term testing under the service conditions. Tensile tests at 1370°C in ambient air have been conducted on silicon nitride alloys to 5000 h with reports of 10,000 h tests for silicon carbide. To provide useful data, such long-term tests must incorporate such meticulous attention to detail as: strict temperature control (±5°C); accurate temperature measurement (1 percent of the nominal temperature); close control of grip cooling (±0.1°C) and ambient environment (±0.25°C); stable, high-resolution extensometry (±0.5 μm); reliable heating (MTBF > 10,000 h) and load control (gravity-controlled, dead load), and responsive data acquisition systems (12-bit, digital collection). Data thus obtained can be used as input into design codes such as NASA CARES/LIFE to predict and confirm reliability/durability.

Copyright © 1996 by The American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In