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The paper presents a crack path development in plane specimens undercyclic bending and the test results for fatigue crack growth in 18G2A steel for threekinds of stress concentrators. The tests were done for constant amplitude of the bendingmoment with the stress ratio R = - 1 on specimens with the stress concentrators beingone-sided sharp and blunt and two-sided sharp notches. It has been found that in thecase of sharp notches a fatigue crack path development proceeds according to Mode Iparalel to the specimen height or with a slide divergence of the vertical axis. In the caseof blunt notched specimens, different crack developments could be observed (they werecurved or straight with a slight divergence). The tests showed that the shortest lives ofthe tested material were obtained with one-sided sharp notch and the longest lives wereobtained for one-sided blunt notch under the same loading.