Corrosion performance of SiC ceramic/epoxy composite coatings on carbonsteel in simulated deep-sea and atmospheric conditions

Abstract

A SiC ceramic/epoxy composite coating was prepared and comparatively studied in 3.5 wt% NaCl solution under atmospheric pressure and 60 MPa high hydrostatic pressure using electrochemical measurement technologies and morphology characterization. Results showed that low frequency impedance modulus (|Z|_0.01 Hz) of the coating decreased from 10¹¹ Ω·cm² to10⁸ Ω·cm² after 60-day immersion under high hydrostatic pressure, while that decreased to 10¹⁰ Ω·cm² under atmospheric pressure. The saturated water adsorption of SiC/CC under atmospheric pressure (0.182 %) was lower than that under 60 MPa (0.212 %) after 60-day immersion. SEM revealed that high hydrostatic pressure could significantly exacerbate microstructural degradation on the SiC/CC surface. The prepared SiC/CC exhibited good protective effects on mining vehicles in deep-sea environment.