Stress Corossion Cracking Behavior of 5083 Aluminum Alloy in SSRT

The effect of pre-deformation and strain rate on the SCC behavior of aluminum alloy 5083 in air and 3.5% NaCl solution were studied by using SSRT,scanning electron microscopy(SEM) and transmission electron microscopy(TEM) analyses.The results indicated that aluminum alloy 5083 was almost not susceptible to SCC in air,all fracture surface showed ductile fracture morphology.The alloy was susceptible to SCC in 3.5% NaCl solution,and fracture morphology was showed partially along grain boundaries or phase boundary,with the decrease of strain rate,ISSRT increased,When strain rate was reduced to 1×10-6s-1,the typical characteristics of brittle cleavage fracture were showed.The second phase such as β(Mg5Al8) precipitation and diclocation increased after pre-deformation were the main reasons leading to increasing SCC suscetibility of 5083 aluminum alloy.