Prediction of Fatigue Crack Initiation under Variable Amplitude Loading: Literature Review

Metallic materials are widely employed in engineering constructions, and one of the most common failure mechanisms metals is fatigue failure. Even though metal has been studied for almost 160 years, many problems remain unsolved. Fatigue occurs when metallic material subjected to varying loads, resulting due damage accumulation. The process consists a buildup that leads crack initiation, followed by period growth until critical flaw size reached. sum start phase propagation represents total life. To better understand phenomenon at its different stages predict life, various types prediction models have developed reported literature. This paper reviewed include microstructure scale parameters can be used how cracks under variable amplitude loading, including Modified Tanaka-Mura Model, Acoustic Second Harmonic Generation, Probability Crack Initiation on Defects. For perfect life stress-based approach, strain-based continuum mechanics approach reviewed. purpose this get overview current state approaches initiation with amplitude. Finally, gaps knowledge about loading high temperatures pointed out.