Quasi-Static Crack Growth in Metals at Elevated Temperature - A Review.
Abstract
The literature on fatigue and sustained load crack growth in metals at elevated temperature is examined within the framework of fracture mechanics. Fatigue crack growth (FCG) rates are found to be frequency dependent. A transition from transgranular to intergranular failure modes is noted as frequency decreases. The time-dependent effect on FCG rates comes from oxidation damage and creep crack growth. In extrapolating the low-cycle fatigue laboratory test data to service conditions, the interaction with creep and oxidation can drastically modify the predicted behavior. Quasi-static crack growth is observed at elevated temperature at stress intensity levels well below the materials fracture toughness. Empirical results and theoretical models for prediction of initiation and growth of cracks are critically reviewed. Results are not conclusive as to which fracture parameter should be used for prediction. Guidelines are given for further studies in this area.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1979
- Accession Number
- ADA072347
Entities
People
- L. S. Fu
Organizations
- Air Force Research Laboratory