Two-Parameter Mechanistic model for the Fatigue Crack Growth of Metals

In this paper, a two-parameter mechanistic model for the fatigue crack growth has been developed. Fatigue failure is the major causes of mechanical structural failure. The fatigue failure progress in three stages crack initiation, crack growth and final failure. The fatigue crack growth has been mo...

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Bibliographic Details
Main Author: Tawqeer Zada
Format: Article
Language:English
Published: National University of Sciences and Technology, Islamabad 2019-12-01
Series:NUST Journal of Engineering Sciences
Subjects:
Online Access:https://journals.nust.edu.pk/index.php/njes/article/view/425
Description
Summary:In this paper, a two-parameter mechanistic model for the fatigue crack growth has been developed. Fatigue failure is the major causes of mechanical structural failure. The fatigue failure progress in three stages crack initiation, crack growth and final failure. The fatigue crack growth has been modelled by different approaches, however these approaches are generally empirical. In this paper, a mechanistic fatigue crack growth model is proposed. The striation and its relation to the cyclic load is used for the model development. Scanning electronic microscope results are used to establish relation between striation and crack growth. The developed model is two-parameters. The model has been implemented and validated using experimental data from the literature. The model prediction is satisfactory in region II of the crack growth curve. However, in region I and region III the model deviates from experimental data. It is suggested to incorporate interaction of monotonic and cyclic loading in the mechanistic modelling for the fatigue growth.
ISSN:2070-9900
2411-6319