CREEP FATIGUE, PART I: Compilation of Data and Trends in the Creep-Fatigue Behavior of Low Alloy Steels

This paper describes an attempt to compile the creep-fatigue data of low alloy steels. In part I, international data have been collected to compare the variability that exists in a particular low alloy steel when characterized in different laboratories. From this work of compilation, trends in the creep-fatigue behavior of low alloy steels have been identified in Part II of this paper and a review of life prediction methods and assessments will be discussed in subsequent papers. The creep-fatigue behavior, in general, improved with the increase in chromium content; however, when additional alloying elements were added to a standard alloy system, the creep-fatigue behavior of that alloy deteriorated. There was a threshold temperature limit as well as a threshold hold time beyond which only interactions of creep-fatigue and oxidation occurred and reduced the life considerably. However, limiting values of threshold temperature and hold times for different low alloy steels have not yet been determined