The effect of grain size and grain boundary misorientation on the corrosion resistance of commercially pure aluminium

摘要

Present study investigates the effect of microstructure on electrochemical response of commercially pure aluminium. Electrochemical testing included OCP measurements and potentiodynamic polarization. Results reveal insignificant differences for samples with different grain size, shape and fraction of HAGBs. These parameters are assumed as only slightly affecting electrochemical response. Fe-containing intermetallics have the highest impact, as pits nucleate in their vicinity. In examined materials intermetallic particles retained a consistent size and distribution for all samples. Therefore, no difference in electrochemical parameters or number of pits is observed. The only difference is in the shape of the pits, because dissolution occurred along HAGBs.