The Anticorrosive and Antifouling Properties of Ni-W-P-nSiO₂ Composite Coating in A Simulated Oilfield Environment

Abstract

Aiming at the problem of tubing corrosion and scaling in the oilfield environment, the corrosion and scaling behaviour of nickel-tungsten-phosphorus-silica (Ni-W-P-nSiO₂) composite coatings prepared on L245 is investigated by immersion test, electrochemical measurement and static scaling test. The results indicated that the corrosion rate of Ni-W-P coating (0.1075 mm a⁻¹) was higher than that of Ni-W-P-nSiO₂ coating (0.0552 mm a⁻¹), consistent with the results of corrosion current density (i_corr). It was also found that the compact corrosion product film that forms on the Ni-W-P-nSiO₂ coating consists of Ni₃S₂ and FeO. The average scaling rate and calcium loss rate value of the Ni-W-P-nSiO₂ coating (2.43 × 10⁻⁶  g cm⁻² h⁻¹, 0.0344⁻² cm⁻²) were both lower than those of the Ni-W-P coating (1.53 × 10⁻⁵ g cm⁻² h⁻¹, 0.0542 cm⁻²), which indicates that SiO₂ nanoparticle co-deposition in Ni-W-P coating with the contact angle of 93.71° can improve its antifouling property.