Laser ablation as an analytical control system for ceramic coatings on metals

Abstract

Metals can be coated with ceramic materials with the aim of improving their applications. Electrophoretic deposition (EPD) over a metallic substrate of zinc was used to produce these coatings, using Al₂O₃ slurries of several concentrations (5, 10 and 20 % in mass). The parameters which control the process were modified: electric intensity (10, 20 and 30 mA) and time (10 and 20 min). The nature of the electrolitic process determines a diffusion between the metallic and the ceramic materials, that may produce a variation of the properties of the final product. In order to detect and quantify the possible existence of that diffusion between the contact surfaces of both materials, a solid state laser of Nd:YAG (λ = 266 nm) coupled to an ICP-AES spectrometer was used. This has allowed to determine the evolution of zinc contamination for each of the variables assayed through the whole coating.