Corrosive-erosive effect on AISI D3 steel, 304 stainless steel and CrN/AlN coating in aqueous NaCl slurries
was studied. CrN/AlN multilayer films with a thickness of 3 µm and bilayer period of Λ = 60 nm (50 bilayers) were
obtained by using the physical vapor deposition (PVD) technique (magnetron sputtering). The corrosion-erosion
experiments were performed in a test machine in which the impingement velocity, impact angle, concentration of solids
and pH of the solution were controlled. Polarization curves were simultaneously obtained to correlate the electrochemical
effects to the erosive wear mechanisms. The slurry used consists of silica particles suspended in a mixture of acid solution
and 3.5% NaCl, with a pH value of 5.6. Electrochemical results showed the best corrosion resistance for 304 stainless
steels. Additionally, the surface analysis by SEM micrograph revealed formation of cracks in CrN/AlN multilayers
coating and plastic deformation in both steel substrates (AISI D3 steel, 304 stainless steel), especially when the mean
impact angle is a critical value of 90°. Measurements of critical and passive current densities showed that the behavior of
coated materials differed depending on the substrate that is used. Nonetheless, in a general way, by increasing the impact
angle and by changing its incidence from normal to grazing, it led to a resistance to corrosion-erosion processes.
ZrMoN films on 304 stainless steel as bipolar plates for PEMFCs using physical-vapor-deposition (PVD) technology