Improving the corrosion protection of aluminium alloys using reactive magnetron sputtering

From the polarization curves it can be concluded that magnetron sputter coating with AlNx leads to a higher pitting potential of the three aluminium alloys investigated. The salt spray tested samples also confirm the protective effect of the coatings. In addition we found that AlNx layers with high nitrogen content lead to a stronger shifting in pitting potential than those with low nitrogen content. Anyway, the results of the salt spray testing show that particularly nitrogen-rich AlNx layers are less stable towards NaCl electrolyte.