Pitting corrosion of spray formed Al–Li–Mg alloys

The pitting corrosion behaviour of two new spray formed alloys, designated OX24 and OX27, has been compared with spray formed AA7034 and more corrosion resistant AA5083 by polarisation tests. The new alloys have been designed for use in the aerospace industry where good corrosion resistance and specific mechanical properties are required. OX24 and AA5083 had good corrosion resistance; OX27 pitted immediately showing poor corrosion resistance. However, both OX24 and OX27 show better corrosion resistance than AA7034. Scanning electron microscopy showed that corrosion was associated with intermetallic particles, except in OX24 where initiation appeared not to be associated with the Zr-rich intermetallics.