LAUSR

Recently, we have developed an icosahedral quasicrystal (I-phase) reinforced Al-Cr-Mn-Co-Zr alloy through gas atomization [1-3]. The powders have a nanocomposite FCC Al matrix / I-phase dispersoid microstructure, with Cr, Mn and Co preferentially segregating to the I-phase. The grain boundaries contain two types of precipitates – Co-rich and Mn/Cr-rich. This microstructure is retained during powder consolidation to form bulk material. The consolidated alloy showed promising physical and mechanical properties [1] and remarkable pitting corrosion resistance, outperforming conventional alloys in ASTM salt fog testing [2]. As such, investigations of the pitting behavior and the preferential sites for pit nucleation in the consolidated alloy are of interest.