An Improved Model for Predicting Fatigue Crack Initiation Life of GH4169

Abstract:

An improved model has been developed to predict fatigue crack initiation life using the criterion of minimizing the Gibbs free energy change considering plastic energy. The prediction process was described in this paper and used to predict the fatigue crack initiation life of notched GH4169 superalloy rolled bar at room temperature and 450°C. The results are acceptable for fatigue crack initiation life prediction in engineering experience and show that the improved model for predicting fatigue crack initiation life as an extension of the concept of minimizing the Gibbs free energy change considering plastic energy is adoptable to some superplastic materials such as GH4169.

• Periodical: Applied Mechanics and Materials (Volumes 29-32)
• Pages: 468-473
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.29-32.468
• Online since: August 2010
• Authors: Dong Lei, Ge Li, Bin Kai Shi, Jian Hua Zhao
• Keywords: Fatigue Crack Initiation Life Prediction, GH4169 Superalloy, Gibbs Free Energy

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