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It is well known that the initiation and propagation behaviour of smallcracks is strongly influenced by the microstructure. In addition to the visible structureon the surface the information of 3D microstructure is essential for the evaluation ofinfluencing factors. Investigations of micro-crack behaviour have been performed withintermetallic γ-based TiAl. The material selected is characterised by lamellar coloniesof hard α2- and relatively soft γ-phase as well as by ordered B2-phase along colonyboundaries. Starter notches facilitate systematic studies as cracks initiate from notchtips. In this case artificial notches in the scale less than colony dimensions were madeby the femtosecond pulsed laser technique, which causes no significant damage in thevicinity of the notch. After multistage tensile compression test under increasing loadseveral small cracks were generated and analyzed in SEM. Combining the femtosecondlaser technique with a ICCD- spectrograph it was possible to analyze the surroundingmicrostructure of these micro-cracks and their propagation in depth direction bysuccessive abrasion.