Author(s)

A. S. Toloei, V. Stoilov & D. O. Northwood

Abstract

The electrochemical and corrosion behaviour of a surface is extremely complicated and depends on various chemical, physical and mechanical factors. In this study the effect of different surface roughnesses on the corrosion resistance of nickel in 0.5 M sulphuric acid was investigated. Open circuit potential, corrosion current density, polarization resistance and corrosion rate were measured for surfaces polished with different grits (120, 240, 400, 600 and 1200) of silicon carbide papers. The surface roughness was measured using a profilometry method both before and after corrosion testing. SEM images were taken and compared for all of the samples before and after corrosion tests. The results showed that surface roughness and surface morphology can considerably change corrosion and corrosion rate. A higher corrosion resistance is obtained for surfaces with lower roughnesses. Finally, the results were compared with specimens where a specific surface patterning was obtained using a laser ablation method. Keywords: corrosion, nickel, surface roughness.

Keywords

corrosion, nickel, surface roughness