Effect of Friction Stir Processing on Pitting Corrosion and Intergranular Attack of 7075 Aluminum Alloy

The effect of friction stir processing (FSP) on the pitting corrosion and the intergranular attack of 7075 aluminum alloy was investigated. Three friction stir processed samples were produced by employing a constant tool travel speed of 100 mm/min at the rotating speeds of 630, 1000 and 1600 rpm. It was demonstrated that the processed samples suffered from both pitting and intergranular corrosion. Also, the sample processed at 1600 rpm exhibited the best pitting corrosion resistance. For all FS processed samples, the corrosion attack in the heat affected zone was pitting corrosion, whereas no intergranular corrosion was detected in this area.