Critique of predictive methods for creep-fatigue at high temperatures
Improved prediction methods for creep-fatigue life will assist in reducing life cycle costs and increasing the integrity of the hot-section components in aircraft engines.Literature on creep-fatigue life assessment is reviewed in this presentation,with an emphasis on the life prediction models applied in aircraft engines.Among the methods discussed are method based on Generalization of Coffin-Manson equation,time-and cycle-fraction damage accumulation,methods based on crack-and void-growth considerations.The development history of each method is reviewed.It can be found that from the early 1990s,the list of new or revised models had been growing at an average rate of approximately five per year.Examples are provided to demonstrate the procedures involved in each method,and the calculations are compared with existed experimental creep-fatigue results.The effects of holding time,inelastic strain range,temperature on the creep-fatigue life and prediction capacity of life prediction models were investigated in detail.The strengths and limitations of each method are included through the error analyses.Each method has enjoyed some degree of success in dealing with a specific set of creep-fatigue data.Because of the complexity of the fatigue process in the creep range,a consensus has not yet been reached regarding the best procedure.The review concludes by indicating areas where knowledge is deficient and where further research would be most beneficial.
S.T.Tu X.C.Zhang
East China University of Science and Technology,Shanghai,China
国际会议
International Conference on Airworthiness & Fatigue -7th ICSAELS Series Conference(大飞机安全性能与疲劳国际会议)
北京
英文
155-155
2013-03-24（万方平台首次上网日期，不代表论文的发表时间）