The influence of grain size and grain orientation on sensitization in AA5083

Aluminum alloy AA5083 specimens (with a nominal composition of Al-4.4Mg-0.5Mn) from the same original plate were prepared with a variation in grain size imparted by cold rolling, cryorolling. Equal channel angular pressing and high-pressure torsion. Electron backscatter diffraction was used to determine the grain size and misorientation. The effect of grain size on the degree of sensitization for AA5083 was studied via the ASTM G67 nitric acid mass lost test, upon specimens artificially sensitized at 150°C for 7 d. It was revealed that the intergranular corrosion caused by sensitization in AA5083 was significantly influenced by the grain size and processing methods used for grain refinement.