Research on the Dependence between the Fatigue Life of X20CrMoV12.1 and P91 Steels under the Conditions of the Interactions of Thermo-Mechanical and Isothermal Low-Cycle Fatigue

Abstract

The paper presents the correlation between fatigue life determined under the conditions of low-cycle fatigue (LCF) and thermo-mechanical fatigue (TMF). Fatigue life values computed using own parameter P and results obtained based on the author’s own research and literature from the publications have been shown. The tests LCF and TMF have been performed for steels used for devices operated in the power engineering industry under the conditions of variable mechanical and thermal interactions X20CrMoV12.1 and P91.

The Influence of the Grade of Materials and their State on the Thermo-Mechanical Behaviour of the Chosen Power Plant Components

“…Material characteristics were determined in a static tensile tests and low-cycle fatigue (LCF) tests [5,6]. These characteristics are represented, among others, by cyclic strengthening curves and durability charts based on values obtained in fatigue tests (Fig.…”

“…5. Durability characteristics are considered as relationships between parameter P, which is the product of the plastic strain range, the range of stress, and the maximum temperature of the fatigue cycle [5,6]. The analysis of the applicability of the parameter P for the thermo-mechanical fatigue life assessment is the special part of our research, which is the subject of the other works.…”