PSI - Issue 18

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com ScienceDirect

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ScienceDirect

Procedia Structural Integrity 18 (2019) 532–537

25th International Conference on Fracture and Structural Integrity Fatigue Testing at 1000Hz Testing Frequency Markus Berchtold*, Ingbert Klopfer RUMUL Russenberger Prüfmaschinen AG, Gewerbestrasse 10, 8212 Neuhausen am Rheinfall, Switzerland 25th International Conference on Fracture and Structural Integrity Fatigue Testing at 1000Hz Testing Frequency Markus Berchtold*, Ingbert Klopfer RUMUL Russenberger Prüfmaschinen AG, Gewerbestrasse 10, 8212 Neuhausen am Rheinfall, Switzerland

Abstract There is no infinite fatigue life. In the recent decades we learned that fatigue testing with higher number of load cycles is required in some areas. The development of faster testing techniques e.g. Ultrasonic systems testing on 20kHz have allowed the conduction of many research activities in the giga cycle regime in the recent decades. In 2014 RUMUL could present a new resonant fatigue testing machine, with a testing frequency of 1000Hz. The dynamic load of maximum 50kN peak-peak is produced with an electromagnetic system. The static portion of the load is provided by two mechanical spindles, the maximum load of the system is +/- 50kN. Any load ratio can be selected. Flat and round specimen types that are normally used in fatigue testing can be used. The actually tested material volume is larger than the material volume that is tested on ultrasonic systems. The new testing machine offers new possibilities for investigations of material properties in the very high cycle fatigue (VHCF) regime. In the past years the new testing machine was intensively used in several laboratories in Germany for example at the laboratory of the Fraunhofer institute IWS Dresden in Germany. Some effects of the 1000Hz testing frequency on the fatigue behavior of the material have been observed. This paper provides a summary how the frequency of an alternating load affects fatigue life of a material. And it highlights some of the found frequency related effects on fatigue strength. Some examples of heating up of the specimen related to the 1000Hz testing frequency are shown. Normally continuous fatigue testing is possible, without stopping for cooling down the specimen. Abstract There is no infinite fatigu life. I the recent decades we learned that fatigue testing with higher umber of load cycles is required in some areas. The development of faster testing techniques e.g. Ultrasonic systems testing on 20kHz have allowed the conduction of many research activities in the giga cycle regime in the recent ec des. In 2014 RUMUL could present a new resonant fatigue t sting chine, with a testing frequency f 1000Hz. The dynamic load of maximum 50kN p ak-peak is pro uced with an electromagnetic system. The static portion of the loa is provided by two mechanical spindles, the maximum load of the system is +/- 50kN. Any load ratio can be s lected. Flat d round specimen types that are normally used in fatigue testing can be used. The actually tested material v lume is larger than the material volume t at is tested on ultrasonic systems. The n w testing machine offers new possibilities for investigations of material properties in the very high cycle fatigue (VHCF) regime. In t past years the new testing machi e was intensively used in several laboratories in Germany for example at the laboratory of the Fraun of r institute IWS Dresden in Germany. So e effects of the 1000Hz testi g freque cy n the fatigue behavior of the material have been observed. This paper provides a summary how the frequency of an alternating load affects fatigue life of a material. And it highlights some of the found frequency related effects on fatigue stren th. Some examples of heating up of the spe ime related to the 1000Hz testing frequency are shown. Normally continuous fatigue testing is possible, without stopping for cooling down the specimen.

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. Keywords: New Resonant Fatigue Testing Machine; Giga cycle (VHCF); Frequency effects Keywords: New Resonant Fatigue Testing Machine; Giga cycle (VHCF); Frequency effects

* Corresponding author. E-mail address: mberchtold@rumul.ch * Correspon ing autho . E-mail address: mberchtold@rumul.ch

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. 2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo.

2452-3216  2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. 10.1016/j.prostr.2019.08.197