A Fracture Mechanics Approach to Creep Crack Growth
- 1 January 1976
- book chapter
- Published by ASTM International
- p. 128-148
- https://doi.org/10.1520/stp33943s
Abstract
A fracture mechanics approach was used to study high-temperature creep crack propagation. Crack growth rates were correlated with the C*-parameter which is an energy rate line integral. For materials conforming to a nonlinear stress and strain rate relationship in the steady-state creep range, specifically, those which can be properly idealized as purely viscous (negligible elastic and transient creep effects), C* characterizes the crack tip stress and strain rate fields. Crack growth rate tests were conducted in the creep range on a discaloy superalloy at 1200°F (920 K). Two specimen geometries were tested, a center cracked panel and a compact geometry, to establish the geometry independence of this approach. The results showed that crack growth rate correlated with the C*-integral, while other parameters (K and nominal stress) failed to adequately characterize crack growth rate.Keywords
This publication has 3 references indexed in Scilit:
- The J Integral as a Fracture CriterionPublished by ASTM International ,1972
- Plastic stress and strain fields at a crack tipJournal of the Mechanics and Physics of Solids, 1968
- Plane Strain Crack Toughness Testing of High Strength Metallic MaterialsPublished by ASTM International ,1966