Effect of Wear on the Corrosion Behavior of High-Velocity Oxygen Flame-Sprayed FeCr35Ni20Mn10B8Mo5Al1.8Si1.5 Amorphous Alloy Coating

Many special components such as catapult guide rail‌, turret base, flight deck, bomb sales, etc., suffer from continuous salt fog corrosion with irregular and intermittent heavy load wear in the marine environment, which leads to serious damage to equipment. This kind of wear–corrosion allows the accumulation of corrosion products, which is different from continuous coupled wear and corrosion. However, the corrosion problems for these components are serious, and how the corrosion products, after wear, influence the corrosion is not well known. In the present work, a newly developed FeCr35Ni20Mn10B8Mo5Al1.8Si1.5 (FAA) coating was chosen to evaluate the effect of wear on the corrosion behavior in seawater. The corrosion behaviors of the high-velocity oxygen fuel (HVOF)-sprayed FAA coating were investigated after wear under different loads by PDP and EIS; the corrosion products in the wear trace were analyzed with SEM, EDS, and XRD. The results indicate that the HVOF FAA coating has a dense structure with a porosity of 3.12 ± 0.25%, an amorphous content of 85.5 ± 4.3%, a bonding strength above 38.9 ± 6.7 MPa, and a hardness of 655 ± 48 HV0.2. Under low-to-medium intensity pre-wear, the wear-induced formation of a dense oxidation layer effectively enhances the corrosion resistance, resulting in the corrosion rate of 0.307 μA/cm2 being a bit higher than that of the as-sprayed FAA coating (0.260 μA/cm2). Conversely, under high-intensity wear, mechanical force tears down the surface protective layer, resulting in a substantial degradation in the anti-corrosion barrier. The sample subjected to 30N and 300 mm/s exhibits a corrosion current density of 1.67 μA/cm2.