PSI - Issue 38

ScienceDirect Structural Integrity Procedia 00 (2021) 000 – 000 Structural Integrity Procedia 00 (2021) 000 – 000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 38 (2022) 192–201

© 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Fatigue Design 2021 Organizers The results show that the modelled strain hot spots are coinciding with the observed crack initiation. A reoccurring sequence can be found in the impact of strain axis ratios on specimen life. Also, curve shift factors to compare the different combinations of axis ratio, temperature and hold time debit with uniaxial fatigue life data, have been identified. © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Fatigue Design 2021 Organizers Keywords: multiaxiality; bi-axial fatigue; FEM; multiaxial lifetime , In this study, he fatigue life of a cast steel is investigated systematically using a servo-hydraulic bi-axial test machine with induction heating. Each xperim nt is ac ompanied with fini elem nt simulatio s before and after the test to par metrize e load ng condition nd derive hot-spot equivale t loading param t rs. The i p ct of different load axis ratios is investigated systematically under displacement con rol as well s the effect of hold times. The esults show that the modelled strain hot sp ts are coinciding with the observed crack initiation. A reoccurring sequence can be found in t e imp ct of strain axis ratios on s ecimen life. Also, curve shift factors to compare he diffe nt combinations of axis rati , temperature and hold time debit with uniaxial fatigu life data, have been identified. © 2021 Th A thors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der re ponsibility of scientific committe of the Fatigue Design 2021 Organ z rs K ywords: multiaxiality; bi-axial fatigue; FEM; multiaxial lifetim , FATIGUE DESIGN 2021, 9th Edition of the International Conference on Fatigue Design A systematic experimental study on the impact of multiaxiality on fatigue life of cast steels at high temperature Alexander Erbe a, *,, Fabian Conrad a , Karl Michael Kraemer a , Christian Kontermann a , Massimiliano Bianchini b , Dirk Kulawinski b , Matthias Oechsner a a Technical University of Darmstadt ,Chair and Institute for Materials Technology IfW, Grafenstrasse 2, 64283 Darmstadt, Germany b Siemens Energy Global GmbH & Co. KG, Rheinstrasse 100, 45478 Muelheim an der Ruhr, Germany Abstract Rising demands on material performance at high temperature in components under complex loading such as gas turbine housings demand an increase in versatility and precision of component life modelling approaches. However, the database to train those models is commonly derived from uniaxial testing. The impact of multiaxial loading, both proportional and non-proportional, is usually addressed theoretically by the use of equivalent stress/strain formulations or reduction ratios derived from selective validation testing. In this study, the fatigue life of a cast steel is investigated systematically using a servo-hydraulic bi-axial test machine with induction heating. Each experiment is accompanied with finite element simulations before and after the test to parametrize the loading condition and derive hot-spot equivalent loading parameters. The impact of different load axis ratios is investigated systematically under displacement control as well as the effect of hold times. FATIGUE DESIGN 2021, 9th Edition of the International Conference on Fatigue Design A systematic experimental study on the impact of multiaxiality on fatigue life of cast steels at high temperature Alexander Erbe a, *,, Fabian Conrad a , Karl Michael Kraemer a , Christian Kontermann a , Massimiliano Bianchini b , Dirk Kulawinski b , Matthias Oechsner a a Technical University of Darmstadt ,Chair and Institute for Materials Technology IfW, Grafenstrasse 2, 64283 Darmstadt, Germany b Siemens Energy Global GmbH & Co. KG, Rheinstra se 100, 45478 Muelheim an der Ruhr, Germ ny Abstract Rising demands on material performance at high temperature in components under complex loading such as gas turbine housings deman an i crease in versatility and precision of compon nt life m d lling approaches. H wever, the database to train those models is commonly derived from uniaxial testing. The impact o multiax al loading, both pr portional and non-pr port onal, is usual y addressed theoretically by the use of equival nt stress/strain formu atio s or reduction ratios derived f m selective validation testing.

* Alexander Erbe E-mail address: alexander.erbe@tu-darmstadt.de * Alexander Erbe E-mail address: alexander.erbe@tu-darmstadt.de

2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Fatigue Design 2021 Organizers 2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der re ponsibility of scientific committe of the Fatigu Design 2021 Organ z rs

2452-3216 © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Fatigue Design 2021 Organizers 10.1016/j.prostr.2022.03.020