INVESTIGATION OF MECHANICAL PROPERTIES AND FATIGUE LIFE OF AL-5083 SHEETS PROCESSED BY EQUAL CHANNEL ANGULAR ROLLING

Equal Channel Angular Rolling (ECAR) is a continuous severe plastic deformation process. In this process, severe shear strains are applied to the sheet. This strain increases the yield or ultimate strength of sheet without signicant change in sheet dimension. In this article, the eect of ECAR process on mechanical properties and fatigue life of manufactured sheets will be studied. Four Al-5083 samples have been prepared and annealed for obtaining stress-free samples. Three samples have been rolled by ECAR process with 1, 2, and 3 pass of rolling, respectively. Mechanical tests including tensile test, hardness, and axial fatigue tests have been carried out on prepared samples. Fatigue tests have been implemented according to strain-based approach with constant strain ratio and 0.5 Hz frequency of loading. Strain ratio (ratio of minimum strain to maximum strain in each cycle) is selected which equals 0.75. All of the tests have been carried out in a controlled laboratory condition. Fatigue life of samples is dened as the total of cycles before complete rupture of samples. Results show that the ultimate tensile strength (UTS) of samples increases with increasing the pass of rolling. Also, the maximum elongation of samples decreases. Maximum elongation was 17% in annealed sample, while it decreases to 10% in sample with three pass of rolling. The hardness of samples has been measured by Vickers micro harness test. The hardness of samples increases at higher pass of rolling. Fatigue test results show that fatigue life of Al-5083 samples decreases in manufactured sheets of equal channel angular rolling process.