Effect of Stress Ratio on Fatigue Crack Growth Threshold for Austenitic Stainless Steels in Air Environment

Abstract:

The fatigue crack growth threshold ΔK_th is an important characteristic of crack growth assessment for the integrity of structural components. However, the accurate threshold ΔK_th values for austenitic stainless steels in air environment are lacking in many fitness-for-service (FFS) codes, although fatigue crack growth tests have been performed and many test data had been published. This paper focuses on fatigue crack growth threshold ΔK_th values for austentic stainless steel in air environment. The paper introduces the current ΔK_th values provided by four major FFS codes and summarizes the available test data based on the literature survey. The paper then discusses the applicability of the existing ΔK_th for stainless steels and proposes a new relation as a function of the stress ratio (the R ratio) for use by FFS codes.

• Periodical: Key Engineering Materials (Volume 741)
• Pages: 88-93
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.741.88
• Online since: June 2017
• Authors: Kunio Hasegawa*, Saburo Usami
• Keywords: Austenitic Stainless Steel, Fatigue Crack Growth Threshold, Stress Ratio

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