Effect of Different Holding Times on The Facture Behavior for Low Cycle Fatigue of Aluminum Alloy aa6063 at 350 ° c Temperature

Abstract

low Cycle Fatigue behavior of aluminum alloy AA6063 heat treated at 350 ° c with different holding times was studied . Constant S – N Curve is designed with the main fatigue parameters . The results are verified with that obtained numerically . Using different holding times with low cycle fatigue properties AA6063 have been observed . Holding times of 2 , 4 , 6 and  8 hours at 350 ° C temperature was used . The yield stress and the ultimate tensile strength were decreased with the increasing the holding time . The strength Coefficient K and the strain hardening index n results were increased as the holding time temperature increased . Also the exponent b of fatigue strength and the exponent C of fatigue ductility  were increased as the holding time increased . Cyclic elastic Strain do not change much with increasing the time at Same temperature 350 ° C and the situation is also the Same for fatigue strain coefficient , for the cyclic plastic strain - Optic Micrograph images were taken using variable magnification before and after fatigue test . Moreover the failure mechanisms with microstructural features are studied using scanning electron microcopy (SEM)