THE USE OF THE SPECIFIC HEAT LOSS TO ANALYSE THE LOW- AND HIGH-CYCLE FATIGUE BEHAVIOUR OF PLAIN AND NOTCHED SPECIMENS MADE OF A STAINLESS STEEL

Development of experimental equipments able to provide the whole temperature field have given impulse to energy related fatigue studies, since temperature is an indicator of the heat loss. In the present paper the specific heat dissipation is assumed to be a fatigue damage parameter. A simple equation and the associated experimental technique previously published by the authors to estimate the specific energy loss is first recalled. Then it is shown that the fatigue behaviour of a stainless steel material can be characterised by a log-log plot of the specific heat loss versus number of cycles characterised by a constant slope from few hundreds to two million cycles. Further it has been found that plain and notched fatigue data collapse into the same energy-based scatter band. Finally a comparison of the proposed approach with the classical local strain method is performed.