Probabilistic Description of Fatigue Crack Growth Under Constant-and Variable-Amplitude Loading
Abstract
This report is concerned with the description of the development and application of a stochastic crack growth model. It is built as a discontinuous Markov process and is inhomogeneous with respect to the number of cycles required for the crack to reach a specified crack length. The model is then used to describe the evolution of the crack length in terms of growth curves, each of whose points possess equal probability of advancing from one position to another forward position. The validity of the model is established by applying it to constant-as well as to variable amplitude loading. In those applications the theoretical constant probability crack growth curves generated by the model compared to those experimentally obtained using Al 7075-T6 and Al 2024-T3 material for constant-amplitude loading while Ti-6Al-4V was used in single overload application. Results of these comparisons indicate the ability of the proposed model when fitted with parameters whose values can be obtained from a limited numbers of experimental tests, to predict the crack growth statistics under different loading conditions. Keywords: Crack; Overload; Stochastic process; Retardation; Titanium alloy; Aluminum alloys; Vanadium.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1989
- Accession Number
- ADA208717
Entities
People
- H. Ghonem
- M. Zeng
Organizations
- University of Rhode Island