Inexpensive production of hydrophobic and corrosion resistant titania-silica composite coatings for deep water sandwich pipe applications

Abstract

ABSTRACT In this study, a multifunctional coating that may be both hydrophobic and corrosion-protective for aluminium sandwich pipes for deep sea applications is developed using the sol–gel dip-coating method. Tiania/silica composite gels were synthesised via sol–gel synthesis, and coatings were deposited on aluminium sandwich pipe substrates using a lab-manufactured dip-coater. XRD (X-Ray Diffractogram) analysis of the as-deposited coatings on the aluminium sandwich pipe revealed anatase phase of titania and amorphous nature of silica with a broad peak at Bragg angle 25°. Fourier transform infrared (FTIR) spectroscopy on the dip coated aluminium substrate revealed Si-O-Ti and Ti-O-Ti stretching vibrations at wavenumbers 906 cm−1 and 768 cm−1, respectively. Wetting investigation on the composite titania-silica coated aluminium substrate utilising the sessile drop technique supported the 123°Contact angle while interacting with a water droplet. Additionally, corrosion resistance examination on the coating was done using sodium chloride solution with salt spray test as per ASTM B117 and indicated no development of white and red rust on the dip coated composite titania-silica aluminium substrate.