THE CE-MO PROCESS FOR THE DEVELOPMENT OF A STAINLESS ALUMINUM

A process for surface modification of Al-based materials is described which involves immersion in boiling Ce(NO3)3 and CeCl3 followed by anodic polarization in a deaerated molybdate solution. Each of these steps is carried out for 2 h. Al 6061-T6 treated in this manner did not show any sips of uniform or localized corrosion after immersion for 60 days in 0.5 N NaCl. A sample with a scratch in the modified surface also did not show any corrosion after 25 days in NaCl. Since this surface modification process produces exceptional corrosion resistance, it should be considered as a candidate for the replacement of chromate conversion coatings.