Corrosion characteristics of microwave and furnace annealed electroless Ni-P-TiO₂ coatings

Abstract

The Co-deposition of TiO2 particles (anatase type) of 200–300 nm with Ni-P electroless coatings on low carbon steel. The coated specimen was annealed by microwave and common electric furnace. The effects of microwave and furnace annealing temperatures on these coatings were characterized via. XRD, SEM, EDAX, and the corrosion performance was characterized through electrochemical polarization technique. The corrosion medium used for this work was sodium chloride (NaCl) solution and which contains 3.5 wt-% in distilled water. The result showed that, the microwave annealing method was enhanced the corrosion performance of the coating by diffused TiO2 particle into the matrix and reduced the micro voids presented in the matrix. Further, the corrosion mechanisms of the non-treated and the annealed coated materials have been explained in the consideration of crystallization, transformation of phases, grain size, and micro strain.