Ermittlung bruchmechanischer Kennwerte an austenitischen Werkstoffen nach der Einprobentechnik mittels Gleichstrompotentialsondenverfahren

J-R-Curve Determination on Austenitic Steel Using Single Specimen Technique with DC-Potential-Drop For the evaluation of fracture mechanical properties several methods will be normally used for ductile materials. For the fracture mechanical investigation of very ductile materials there is no standard method achievable at present. Performing continuous measurements of crack length in materials of high ductility appears most difficult. This paper deals with the continuous determination of crack length in two different samples of high ductile austenitic steel by means of DC-potential drop. Due to the indirect way of crack length determination using this method a correction factor depending on deformation has to be introduced. By this it is possible to construct the J-R-curve using single-specimen technique and to evaluate a J₀ value using fractographical methods. Because of rather large displacements arising with fracture mechanical tests of austenitic steels a formula for the correction of the load line displacement is introduced and discussed. The method presented leads to reproducible results which correspond with results obtained using multiple specimen technique.