Electrolytic Production and Structure of Ni+AI+Ti Composite Coatings

摘要

The Ni+AI+Ti composite coatings were prepared by the electrodeposition under the galvanostatic conditions at the deposition current denisty of j_(dep) = -225 mA cm~(-2). Phase composition investigations were conducted by X-ray diffraction (XRD) method. The surface morphology, cross-section and chemical composition of the coatings were examined using a scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. Thermal treatment of the obtained composite coatings was conducted in argon atmosphere at the temperature of 800°C for 12 h. It was found that the as-deposited Ni+28at.%Al+25at.%Ti composite coating is a three-phase material (Ni, Al and Ti phases). The thermal treatment caused the chemical reaction in solid state of the heated coating, and a new multi-phase material was formed containing Ni and Al metallic phases as well as NiAl, Ni_2AI_3, Ni_3AI， NiTi， NiTi_2 and Ni_3Ti intermetallic phases. Thus obtained composite coatings may be useful in the applications as materials in the electrochemical processes.