Development of generic creep-fatigue life prediction models

This paper presents a data bank that was compiled from published and unpublished sources. Using these data, low cycle fatigue curves were generated under a range of test conditions showing the effect of test parameters on the Coffin-Manson behavior of steel alloys. Phenomenological methods of creep-fatigue life prediction are Summarized in a table showing number of material parameters required by each method and type of tests needed to generate such parameters. Applicability of viscosity method was assessed with creep-fatigue data on 1Cr-Mo-V, 2.25Cr-Mo and 9Cr-1Mo steels. Generic equations have been developed in this paper to predict the creep-fatigue life of high temperature materials. Several new multivariate equations were developed to predict the creep-fatigue life of following alloy groups; (1) Cr-Mo steels, (2) stainless steels and (3) generic materials involving the materials from the following alloy groups, solder, copper, steels, titanium, tantalum and nickel-based alloys. Statistical analyses were performed in terms of coefficient of correlation (R-2) and normal distribution plots and recommended these methods in the design of components operating Lit high temperatures. (C) 2003 Elsevier Ltd. All rights reserved.