Thermally sprayed alumina nano-coating using the solution precursor plasma spray system

Nanostructured coatings have been the subject of high interest in the oil and gas industry due to their superior properties, such as corrosion and wear resistance. Alumina nano-coatings were developed in-house by a solution precursor plasma spray (SPPS) technique using the thermal plasma spray process at different operating conditions to achieve good corrosion resistance. Three different concentrations and flow rates were used in this study to optimize the spray parameters, and consequently, to minimize the consumption of the precursor. The produced coating systems were characterized using several techniques, including X-ray diffraction (XRD) and scanning electron microscope (SEM). The characterization data confirmed the nanostructure nature of the produced nano-oxide layer. Also, corrosion testing using a salt spray technique indicated slight improvements in the corrosion protection for the carbon steel coupons. Moreover, the coating adhesion was found to be significantly influenced by changing the concentration of the precursor as well as the spraying flow rates.