Chapter 42. Mechanical Behavior of a Sumitomo Alumina Fiber at Room and High Temperature
- John B. Wachtman Jr.
Published Online: 28 MAR 2008
Copyright © 1989 The American Ceramic Society, Inc.
A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 9/10
How to Cite
Jakus, K. and Tulluri, V. (1989) Mechanical Behavior of a Sumitomo Alumina Fiber at Room and High Temperature, in A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470310588.ch42
- Published Online: 28 MAR 2008
- Published Print: 1 JAN 1989
Print ISBN: 9780470374870
Online ISBN: 9780470310588
- composite density;
- mechanical property enhancement;
- fracture toughness;
- stress intensity;
- elastic modulus
The strength, fatigue, and creep characteristics of a Sumitomo organometallic polymer precursor-derived fiber was measured in the temperature range from room to 1200°C. The fiber had a nominal composition of 85% alumina and 15% silica. Batches of 25 specimens were tested in room temperature air with two different gauge lengths and three different strain rates. The median strength of 10 cm long specimens tested at 0.05 min−1 strain rate was 1.5 GPa. Scatter in strength was relatively large at all test conditions giving a Weibull modulus between 4 and 6. This Weibull modulus accurately predicted the measured gauge length dependence of strength. Room temperature fatigue susceptibility was lower than that for typical polycrystalline aluminas, having a value for the fatigue constant N between 70 and 100. Strength was found to degrade with increasing temperature. At 1200°C the strength was 42% of the strength at room temperature. Substantial creep deformation occurred at temperatures above 1000°C. The stress exponent for creep ranged from about 1 to 2.4 depending on the temperature, and the average activation energy was 470 KJ/mole.