A common problem in the production of a centrifugal pump is the corrosion caused by fluid communication. The use of nano-coatings is one of the most effective methods for preventing and postponing corrosion. Nano-coatings have a higher thermal expansion coefficient, higher hardness and toughness, and more resistance to corrosion, abrasion and erosion. The purpose of this study was to investigate the effect of TiO2nano-particle coating on the construction of corrosion resistant blades of centrifugal pumps. Thin layers of titanium dioxidenano-particles were created in two separate steps on GG25 gray cast iron samples with specific dimensions and characteristics using the sol-gel process and immersion method. After each step, heat treatment was performed to stabilize the nano-coating. The thickness of applied coatings was measured by scanning electron microscopy (SEM). In order to measure the corrosion rate, the samples were exposed to petrochemical wastewater. The corrosion rate was measured by atomic absorption spectrometry method. The experiments were carried out in a factorial arrangement in a completely randomized design with three temperature levels of 40, 50 and 60 ºC and four thicknesses. The results showed that coating of titanium dioxide nano-particles increased the corrosion resistance of GG25 gray cast iron. With an increase in temperature from 40 to 60 ºC, the corrosion rate of all samples increased by 46.6%. Coated samples with thicknesses of 440-550, 840-970, and 1030-1330nm reduced corrosion rates by 39.1%, 67.8% and 73.6%, respectively.
