Abstract
Early detection of a growing crack is one of the concerns in structural integrity and can be used to predict the remaining useful life of a structure. Acoustic Emission (AE) is a nondestructivetesting method with potential applications for locating and monitoring fatigue cracks. A novel AE signal analysis approach is proposed in this paper to detect crack initiation and assess small crack growth behavior. A probabilistic AE-based model for small fatigue cracks was developed and the uncertainties of the model were estimated. The outcome of this research can be used to evaluate the integrity of structures and assess structural health by estimating the probability density function of the length of detected cracks. This paper discusses the methodology used, experimental approach, results obtained and predictive models developed.
Highlights
In materials engineering, fatigue cracking occurs when a material is subjected to cyclic loading
The results show that the developed AE-model reasonably estimates the true crack length
Investigation of the uniform cyclic loading tests on Al7075-T6 specimens indicated that initiation of cracks smaller than the grain size could be identified using statistical analysis of the resulting AE signals
Summary
Fatigue cracking occurs when a material is subjected to cyclic loading. A rich array of recent research in the literature deals with the probabilistic approaches that combine Nondestructive Evaluation (NDE) methods for detecting materials damage, especially for evaluating fatigue failures. INTERNATIONAL JOURNAL OF PROGNOSTICS AND HEALTH MANAGEMENT stages of damage accumulation compared to the later stages, and attribute this to material inclusions that crack in the early degradation periods These studies hypothesize crack propagation rate based on the AE signals, but do not directly correlate them to crack initiation, nor do they consider associated crack detection probability and crack sizing errors using the detected AE features. The developed model can be used for detection of crack initiation as well as assessment of small crack growth behavior This method can be used to assess the reliability of structures and evaluate health by estimating the probability of structure failure at a specified number of cycles, including associated uncertainties
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
