LOW CYCLE FATIGUE BEHAVIOR OF ALUMINUM ALLOYS AA2024-T6 AND AA7020-T6

Abstract

In this study low cycle fatigue tests were performed in two aluminum alloys with different chemical composition, namely AA2024-T6 and AA7020-T6 under same heat treatment, using standard round specimens. The tests undertaken in strain control with strain ratio R_e = -1.The low cycle fatigue results are used for characterization of the cyclic plastic response and the fatigue life of the alloys. This study revealed that the strength and the different chemical composition have a significant effect on transition fatigue life. The degree of the compatibility and precipitation of elements zinc (Zn) and copper (Cu) on their parent metal lead to obtain higher fatigue properties value in alloy AA7020-T6 than alloy AA2024-T6. Moreover, the cyclic deformation behavior seems to be influenced by the strength and the different chemical composition