In this work , an experimental study to obtain the fatigue endurance limit for two aluminum alloy , 2024 and 5052 , were carried out at stress ratio R=-1 and rotary bending tests . The fatigue tests were performed at RT, 100 °C, 200 °C and 300 °C in order to establish the S–N curve equations. The fatigue endurance limits for both alloys at different temperature conditions were calculated at 107 cycles
from the empirical S-N curve equations. It was found that the fatigue endurance limit decrease with increasing the temperature. Also the reduction percentage in fatigue endurance limit for 5052 Al. alloy was higher than that of 2024 Al. alloy.