An Evaluation of Appropriate Probabilistic ­S-­N Curve for the Turbine Blade Steel in the Low Pressure Steam


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In order to evaluate the variation of fatigue data of turbine blade steel in low pressure (LP) steam, it is important to estimate probabilistic stress-life (P-S-N) curve to accurately define the probability distribution. In this study, a new procedure was introduced to determine the expression of P-S-N curves. For this purpose, 3-parameter Weibull distribution was found to be the most appropriate among assumed distributions when the probability distributions of the fatigue life were examined by a comparative analysis. Furthermore, the parameter of P-S-N curve was evaluated using various optimization techniques to maximize the correlation coefficient. As a result, the sequential linear program method is used for estimation of P-S-N curve.



Key Engineering Materials (Volumes 297-300)

Edited by:

Young-Jin Kim, Dong-Ho Bae and Yun-Jae Kim




C. S. Kim et al., "An Evaluation of Appropriate Probabilistic ­S-­N Curve for the Turbine Blade Steel in the Low Pressure Steam", Key Engineering Materials, Vols. 297-300, pp. 1751-1757, 2005

Online since:

November 2005




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