تحضير و توصيف راسب مركب Ni-TiO2 بتقنية الترسيب الكهربائي

Abstract

Ni-TiO2 composite coatings were elaborated on BS2 mild steel by an electrodeposition method. The specimens were obtained from an electrolytic bath. Concerning Ni-TiO2 composite coatings, this bath contained various contents (5, 10, and 15 g.l-1) of TiO2 particles. X-ray diffraction (XRD) characterization showed that increasing the TiO2 content in the coatings can decrease the crystal grain size. The surface morphology and chemical composition of the composite coatings were modified by the addition of TiO2 particles in the electrolyte, as shown by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) methods, respectively. The TiO2 content also significantly affected the mechanical and electrochemical properties of the Ni-TiO2 composite coatings. The microhardness of the Ni-TiO2 composite coatings can be enhanced by increasing the TiO2 content in the coatings. With the addition of 5 g.l-1 and 10g.l-1 TiO2 particles to the electrolyte, the deposited Ni-TiO2 composite coating presented a remarkably increased corrosion resistance when exposed to 3.5% NaCl at room temperature compared with that of the BS2, but lower than that of Ni coating. Nevertheless, the further addition of TiO2 particles into the electrolytic bath did not further improve the corrosion resistance of the composite coating. Key words: electrodeposition, microhardness , the corrosion.