Statistical Analysis and Reliability Prediction of Creep Rupture Strength and Life for DZ125 Superalloy

Abstract:

This paper presents the reliability analysis of the creep rupture strength and long-term life of a directionally solidified nickel-base superalloy, DZ125, which is widely used for manufacturing turbine blades of advanced aeroengines. A number of creep rupture experiments of DZ125 alloy are carried out at 760^oC, 850^oC, 980^oC and 1040^oC. Larson-Miller (L-M for short) parameter is used to predict the long-term creep life and a master curve in the L-M parameter is obtained. A “Z-parameter” model is employed to characterize the magnitude of the deviation of the creep rupture data to a master curve. The “Z-parameter” of DZ125 alloy followed Gaussian distribution which is verified by Chi-square testing. Based on the “Z-parameter” model, the curves of Stress-TTP (i.e. Time-temperature parameter)-Reliability, Stress-Life-Reliability and Allowable Stress-Temperature-Reliability are obtained to predict the creep rupture strength and life for DZ125 alloy.

• Periodical: Applied Mechanics and Materials (Volume 750)
• Pages: 133-138
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.750.133
• Online since: April 2015
• Authors: Cheng Li Dong, Ying Li, Hui Chen Yu*
• Keywords: Creep Life, Directionally Solidified Superalloy, Master Curve, Reliability, Z-Parameter

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