Investigation of corrosive and mechanical behaviour of Ni-P doped coating by utilizing electroless method

Abstract

Corrosion is a major concern for steel structures, requiring significant investments for corrosion resistance. This study focused on applying Ni-P and Ni-P with surfactant electroless coatings to TMT steel rebar. The deposition rate of the electroless bath was investigated at different stirrer rotation speeds, with 300 rpm identified as optimal. Morphological and structural analyses were conducted using FESEM and XRD techniques. The average coating thickness reached 131.47 µm at 300 rpm. The addition of admixtures like lactic acid, succinic acid, and citric acid improved coating efficiency. The corrosion behavior of TMT rebar with Ni-P coating and Ni-P with surfactants was examined using EIS and polarization methods. Corrosion current densities were measured as 3.82µA cm-2, 3.91µA cm-2, and 4.1µA cm-2 for TMT steel, Ni-P coated, and Ni-P with surfactant-coated rebars, respectively.