Influence of the Number of Fatigue Cycles on the Peak Shape of X-ray Rocking Curves at Duplex Steel Samples Treated by VHCF

This paper shows results of in-situ X-ray diffraction analysis of VHCF cycles in duplex steel samples measured in reflection geometry at DELTA synchrotron. Due to the grain size a few number of grains inside the illuminated area fulfill the Bragg condition simultaneously and allow single grain analysis. Rocking curves (RC) recorded after N· 107 fatigue cycles (N=0...8) with increasing stress load reveal changes of shape and intensity of selected austenite and ferrite grains as function of N and are interpreted by rotation of diffracting lattice plane due to formation of slip bands.