文献类型：期刊文献

英文题名：Study on creep-fatigue damage evaluation for advanced 9%-12% chromium steels under stress controlled cycling

作者：Zhao, Peng[1]; Xuan, Fuzhen[1]

机构：[1] Key Laboratory of Safety Science of Pressurized System, East China University of Science and Technology, Ministry of Education, Shanghai 200237, China

年份：2011

卷号：24

期号：2

起止页码：148

外文期刊名：Acta Metallurgica Sinica (English Letters)

收录：EI(收录号：20112814144755)

语种：英文

外文关键词：Outages - Damage detection - Stress analysis - Fatigue damage - Fossil fuel power plants

摘要：Creep-fatigue interaction is one of the main damage mechanisms in high temperature plants and their components. Assessment of creep-fatigue properties is of practical importance for design and operation of high temperature components. However, the standard evaluation techniques, i:e. time fraction rule and ductility exhaustion one have limitations in accounting for the effects of control mode on the cyclic deformations. It was found that conventional linear cumulative damage rule failed in accurately evaluating the creep-fatigue life under stress controlled condition. The calculated creep damages by time fraction rule were excessively high, which led to overly conservative prediction of failure lives. In the present study, it was suggested that such over estimation of creep damage was mainly caused by anelastic strain upon stress loading. For precise assessment under conditions of stress control, a modified creep damage model accounting for the effect of anelastic creep was proposed. The assessments of creep fatigue data under stress controlled condition were performed with the new approach developed in this paper for a rotor material and a boiler material used in ultra supercritical power plants. It was shown that a more moderate amount of creep damage was obtained by the new model, which gave better predictions of failure life.