Heat Treatments Effects on the Fatigue Behaviors of Aluminum Nano-Composite Alloys

Abstract

   The fatigue is one of the major reasons for fracture of materials.  Aluminum 7204 AA alloy with various heat treatments and (2.0) wt % of SiC nanoparticles  were prepared by stir-casting method  under rotating bending loading with ratio of stress (R= -1). The composite  was strengthened by SiC particles size of) 10 (nanometre. The fatigue strength and life were  obtained experimentally by  the family of S-N curves for different heat treatments. The endurance limits (10⁷cycles) for 7204 AA/ 2.0wt% SiC nano-composite fatigue strength as related to untreated nanocomposite was enhanced by 72 and 78.5%  for T4 and T6, respectively.The improvement  of fatigue properties  is due to better spreading of SiC nanoparticles and increased  porosity.