Wpływ współczynnika asymetrii cyklu na rozwój pęknięć zmęczeniowych w próbkach poddanych zginaniu

The paper presents experimental tests results of the fatigue crack growth in PA6 aluminium alloy under cyclic bending. Specimens with rectangular cross-sections and stress concentrator in the form of external one-sided notch were used. The tests were performed on the fatigue test stand MZGS-100 in the high cycle fatigue regime for the stress ratio R = - 1; -0,5 and 0. Crack paths was observed on the specimen surface with the optical method.