Ehlers, SörenSörenEhlers11599977990000-0001-5698-9354Hochfellner, VeronikaVeronikaHochfellner2018-05-292018-05-292018http://tubdok.tub.tuhh.de/handle/11420/1651For the purpose of reliable life prediction the fatigue crack growth behaviour of a material has to be well-known. Therefore standardized fatigue crack growth tests are made with test specimens of the material. The obtained fatigue crack growth data is taken as material specific data and is given without any information of the test conditions and used specimen geometry. However, in several studies a geometry dependency of the test specimen on the fatigue crack growth data is found. Hence in this investigation experiments on fatigue crack growth behaviour are made with two different specimen geometries, the middle tension specimen M(T) and the compact (tension) specimen C(T). The direct current potential drop (DCPD) method is used to determine the crack lengths which is calibrated with the aid of beach marks and crack detection gauges. Two different configurations of the DCPD method are implemented to gain acceptable results. With the obtained data fatigue crack growth curves are established which are analysed regarding the geometry influence of the used test specimens. Discrepancies in the fatigue crack growth curves between the tested specimens are found. With these findings an approach is tested to create a material curve which is independent of the specimen geometry. However, this approach is not leading to satisfactory results. The implementation of the DCPD method in its main configuration on the used experimental setup proves to be applicable for fatigue crack growth tests on different geometries and will be used in further studies at low temperatures.enhttp://rightsstatements.org/vocab/InC/1.0/fatigueconstraint effectIngenieurwissenschaftenMaster Thesisurn:nbn:de:gbv:830-8822078810.15480/882.164811420/165110.15480/882.1648Bock und Polach, Rüdiger Ulrich Franz vonRüdiger Ulrich Franz vonBock und PolachBraun, MoritzMoritzBraunOther