Influence of the Friction Stir Welding-Traveling Speed on the Corrosion Properties of Mg-5Al Alloy

A Mg-5Al alloy was processed using the friction stir welding (FSW) technique with traveling speeds ranging from 0 to 80 mm/min. The influence of the FSW-traveling speed on the prepared Mg-5Al alloy was examined using electrochemical and surface analysis techniques. The electrochemical tests revealed that an increasing FSW-traveling speed results in a significant improvement of the corrosion resistance, as characterized by the higher pitting potential and film and charge transfer resistances. The increased corrosion resistance was attributed to the enhanced refinement of the precipitates, grain refinement and increased homogeneity of the microstructure obtained with an increasing FSW-traveling speed.