The Influence of Different Type Materials of Grit Blasting on the Corrosion Resistance of S235JR Carbon Steel

Abstract

The aim of this paper is to evaluate the corrosion rate expressed in material loss per unit of time and the surface properties of carbon steel type S235JR blasted with different types of materials (quartz, alumina, and red garnet with a particle size between 60 and 80 mesh (0.25–0.60 mm)). The estimation of corrosion rate was determined by electrochemical methods, such as open circuit potential (OCP), polarization resistance (Rp), corrosion rate (Vcorr), and gravimetric method by immersing the samples in 3.5% NaCl solution for a period of 336 h. All surfaces were characterized before and after corrosion tests using ex-situ characterizations, such as optical microscopy and roughness analysis. The results indicate that S235JR non-sandblasted exhibited higher polarization resistance, the lowest corrosion rate, and the lowest roughness values. While for the S235JR sandblasted groups, reduced corrosion resistance and increasing roughness values were noted. From the sandblasted groups, the lowest corrosion resistance and the highest value of roughness are attributed to the S235JR surface sandblasted with quartz. The S235JR surface sandblasted with quartz shows a decrease in corrosion resistance approximately two times lower than the non-sandblasted surface and an increasing of roughness approximately six times greater than the non-sandblasted surface.

Keywords

• S235JR carbon steel
• corrosion rate
• sandblasting
• roughness
• optical microscopy