Evaluation of Slow Crack Growth Resistance in Ceramics for High‐Temperature Applications
Authors:
- 1 April 1992
- journal article
- Published by Wiley in Journal of the American Ceramic Society
- Vol. 75 (4) , 772-777
Abstract
The slow (subcritical) crack growth (SCG) resistance of Si3N4 and SiC ceramics has been evaluated by a stepwise loading test on bending bars precracked by Vickers indentation. Three highly refractory materials were selected for the evaluation: i.e., (1) high‐purity Si3N4 sintered by hot isostatic pressing (HIP) without additives and (2,3) α‐ and β‐ SiC pressureless sintered with B and C addition. Under the hypothesis of linear elastic behavior at high temperature, which was found satisfied in the present materials, the SCG resistance was expressed in terms of initial stress intensity factor critical for SCG failure within a predetermined lifetime. The present method was found useful in shortening the testing time and consistent with other traditional fatigue tests (e.g., static‐fatigue test): It is recommended as a screening test for materials under research and development. Among the materials tested in the present study, the highest SCG resistance up to 1440°C was found in the high‐purity Si3N4 without additives.Keywords
This publication has 12 references indexed in Scilit:
- Delayed‐Failure Resistance of High‐Purity Si3N4 at 1400°CJournal of the American Ceramic Society, 1992
- Impurity‐Enhanced Intergranular Cavity Formation in Silicon Nitride at High TemperaturesJournal of the American Ceramic Society, 1991
- Fracture toughness of Si3N4 and its Si3N4 whisker composite without sintering aidsJournal of Materials Science, 1991
- Brittle‐to‐Ductile Transition in Silicon CarbideJournal of the American Ceramic Society, 1989
- Kinetics and Mechanisms of High‐Temperature Creep in Silicon Carbide: III, Sintered α‐Silicon CarbideJournal of the American Ceramic Society, 1988
- Duality in the Creep Rupture of a Polycrystalline AluminaJournal of the American Ceramic Society, 1985
- Static Fatigue Limit for Sintered Silicon Carbide at Elevated TemperaturesJournal of the American Ceramic Society, 1983
- Determination of Threshold Stress Intensity for Crack Growth at High Temperature in Silicon Carbide CeramicsJournal of the American Ceramic Society, 1983
- Further Reply to “Comment on‘Elastic/Plastic Indentation Damage in Ceramics: The Median/Radial Crack System’“Journal of the American Ceramic Society, 1982
- Crack propagation and failure prediction in silicon nitride at elevated temperaturesJournal of Materials Science, 1974