Samples of the ferritic tool steel AISI1045 were fatigued in cyclic loading tests. The local distribution of the Von-Mieses stress σVM was simulated by using the finite elements method. In the regions of interest, where σVM reached maximum values, the defect distribution was spatially resolved by Doppler-spectroscopy using a positron microprobe. The lateral distribution of the S-parameter, which could be described by a simple model derived from linear fracture mechanics, corresponded well with the simulated Von-Mieses stress.

Spatially Resolved Defect Studies on Fatigued Carbon Steel. P.Eich, M.Haaks, R.Sindelar, K.Maier: Physica Status Solidi C, 2007, 4[10], 3465-8