REPRESENTATION OF CYCLIC PROPERTIES AND HYSTERESIS ENERGY IN ALPHA-BRASS USING A CERTAIN CLASS OF ELASTIC-PLASTIC MODELS

The paper deals with the analytical representation of the cyclic stress-strain curve, the hysteresis loop and the hysteresis energy for a single-phase alpha-brass. The The one- and two-parameter elastic-plastic models that were used were so chosen as to produce compatible representation of both the stress-strain relationship and the hysteresis loop. The models were checked with experimental data. The specimens were tested in uniaxial tension-compression (R(epsilon) = -1) under total strain amplitude control. The experiments covered a broad spectrum of lives from the low-cycle region through to the high-cycle regime, i.e. up to lives of N = 1 x 10(6) cycles. The adopted measurement method enabled the cyclic deformation curve, hysteresis loop and hysteresis energy to be determined independently. It was shown that the modified Ramberg-Osgood model is a good approximation to actual cyclic behaviour of alpha-brass.