Microbiologically-influenced corrosion of the electroless-deposited NiP-TiNi – Coating

In this study, we reveal the microbiologically influenced corrosion (MIC) behavior of the new electroless NiP-TiNi nanocomposite coating in simulated seawater using the electrochemical impedance spectroscopy (EIS) technique after different periods of incubation time (7, 10, 14, 21, 28 days) in a sulfate-reducing bacteria (SRB) medium. The biofilm formation and the corrosion products were characterized using the scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The EIS results revealed the carbon steel (CS)/NiP-TiNi and NiP-TiNi/SRB biofilm interfaces' characteristics after different incubation times in the SRB media. EIS measurements revealed that the NiP-TiNi nanocomposite coating's MIC resistances are superior relative to API X80 carbon steel and a TiNi-free NiP coating, with ∼93% of corrosion inhibition efficiency after 28 days of incubation.