Modelling the Probabilistic Fatigue Life Based on Defects Using Extreme Value Statistics for Cast Ni-Based Alloys
Autoren |
Florian Mader |
|---|---|
Medien | In: Huber, O., Bicker, M., Patzelt, P. [Hrsg.]. 12. Landshuter Leichtbau-Colloquium, Leichtbau - Grenzen überwinden und Innovationen gestalten, LC-Verlag, Landshut, ISBN 978-3-9826926-0-9 |
Veröffentlichungsjahr | 2025 |
Seiten | 204-218 |
Herausgeber | Huber, O., Bicker, M., Patzelt, P. |
Veröffentlichungsart | Konferenzbeitrag (peer reviewed) |
Forschungsprojekt | DiWeTwin |
Zitierung | Mader, Florian; Kollmannsberger, Eva; Wagner, Martin; Saage, Holger; Huber, Otto (2025): Modelling the Probabilistic Fatigue Life Based on Defects Using Extreme Value Statistics for Cast Ni-Based Alloys. In: Huber, O., Bicker, M., Patzelt, P. [Hrsg.]. 12. Landshuter Leichtbau-Colloquium, Leichtbau - Grenzen überwinden und Innovationen gestalten, LC-Verlag, Landshut, ISBN 978-3-9826926-0-9, 204-218. |
Peer Reviewed | Ja |
Modelling the Probabilistic Fatigue Life Based on Defects Using Extreme Value Statistics for Cast Ni-Based Alloys
Abstract
Previous studies on aluminium alloys show that material defects in the form of pores have a significant impact on the fatigue lifetime. The aim of this study is to present a method with which the influence of defects in nickel-based alloys can be analysed. For this purpose, micro computed tomography (µCT) analyses were carried out on 14 Inconel 713C material samples. The investigations show that the pores contained in most of the samples are distributed exponentially with respect to the defect size √𝑎𝑟𝑒𝑎. By applying methods of extreme value statistics, the distribution of the largest defect in a prospected component volume 𝑉C can be derived from the distribution of the detected extreme values in the CT-scanned base volume 𝑉S . The proposed model for this calculation shows a strong dependency on the defects contained in 𝑉S . In the cases where 𝑉S is an effective representation of the population of defects occurring in the material, the model demonstrates satisfactory results in calculating the distribution of the largest defect in 𝑉C . By combining the calculated distribution with an appropriate crack propagation model, where the distribution is entered into the model as the distribution of the initial crack lengths, a method is given to calculate the scatter of the fatigue life based on the scatter of the defects.