Improvement of the corrosion resistance of Cr-N coated aluminum matrix composite by magnetron sputter

Cr-N coatings were deposited on alumina borate whisker reinforced pure aluminum matrix composite substrates by radio frequency (RF) magnetron sputtering. The phase and chemical state of coatings were characterized using X-ray photoelectron spectroscope and X-ray diffraction techniques. Corrosion behaviors were investigated in 3.5%NaCl solution at room temperature. Potentiodynamic polarization curves confirm that the Cr-N coated composite shows not only much lower susceptibility to pitting but also significantly improved corrosion resistance in comparison with untreated composite. (c) 2007 Elsevier B.V. All rights reserved.