Assessing the Accuracy of Time‐Fraction and Ductility Exhaustion Approaches for Creep‐Fatigue Damage Prediction in Alloy 617 Through Feature Test Validation.

Saved in:
Bibliographic Details
Title: Assessing the Accuracy of Time‐Fraction and Ductility Exhaustion Approaches for Creep‐Fatigue Damage Prediction in Alloy 617 Through Feature Test Validation.
Authors: Petkov, M.1 (AUTHOR) markianpetkov@gmail.com, Messner, M.2 (AUTHOR), Spindler, M.3 (AUTHOR)
Source: Fatigue & Fracture of Engineering Materials & Structures. Jun2026, Vol. 49 Issue 6, p2429-2448. 20p.
Subjects: Nickel alloys, High temperatures
Abstract: Determining creep‐fatigue damage formation is critical for elevated temperature components integrity. This study evaluates creep‐fatigue assessments with emphasis on differences between creep damage models. Evaluated are the time‐fraction model and the classical and stress‐modified ductility exhaustion creep damage models. This work extends the domain of stress‐modified ductility exhaustion models by introducing and validating such formalism to Ni‐based alloys. The fidelity of the assessments was benchmarked against uniaxial creep‐fatigue and multiaxial feature tests of Alloy 617. For uniaxial specimens, best estimate predictions rank ductility exhaustion as the most accurate and precise and time‐fraction as markedly conservative. For feature tests, ductility exhaustion predictions are within < 4.0 times difference, whereas time‐fraction underpredicts life by factors of 7–14. The observations suggest ductility exhaustion models as alternative to time‐fraction models in design codes for situations requiring characterization of the design margin. Further work in employing such models to assess other relevant phenomena (e.g., stress relaxation cracking) is discussed. Summary: Evaluated are the time‐fraction and ductility exhaustion models for creep‐fatigue damage.Application of models for Alloy 617, beyond creep‐resistant steels, includes various refinement.Validation against multiaxial feature tests with elastic follow‐up is presented.This work assesses life sensitivity to methods and scatter in underlying creep failure data. [ABSTRACT FROM AUTHOR]
Copyright of Fatigue & Fracture of Engineering Materials & Structures is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Determining creep‐fatigue damage formation is critical for elevated temperature components integrity. This study evaluates creep‐fatigue assessments with emphasis on differences between creep damage models. Evaluated are the time‐fraction model and the classical and stress‐modified ductility exhaustion creep damage models. This work extends the domain of stress‐modified ductility exhaustion models by introducing and validating such formalism to Ni‐based alloys. The fidelity of the assessments was benchmarked against uniaxial creep‐fatigue and multiaxial feature tests of Alloy 617. For uniaxial specimens, best estimate predictions rank ductility exhaustion as the most accurate and precise and time‐fraction as markedly conservative. For feature tests, ductility exhaustion predictions are within < 4.0 times difference, whereas time‐fraction underpredicts life by factors of 7–14. The observations suggest ductility exhaustion models as alternative to time‐fraction models in design codes for situations requiring characterization of the design margin. Further work in employing such models to assess other relevant phenomena (e.g., stress relaxation cracking) is discussed. Summary: Evaluated are the time‐fraction and ductility exhaustion models for creep‐fatigue damage.Application of models for Alloy 617, beyond creep‐resistant steels, includes various refinement.Validation against multiaxial feature tests with elastic follow‐up is presented.This work assesses life sensitivity to methods and scatter in underlying creep failure data. [ABSTRACT FROM AUTHOR]
ISSN:8756758X
DOI:10.1111/ffe.70266