Papers by Author: L. Martínez

Abstract: In recent years the use of ceramic coatings to reduce metallic corrosion has been greatly improved. It has been proved by several studies that coating of TiO2, ZrO2, SiO2, and other oxides or mixed oxides provide efficient protection against the corrosion of stainless steel in different media. In this work, alumina and zirconia films were obtained by electrophoretic deposition to investigate their use as protective coatings of 316L-Stainless steel for prostheses and dental implants. These were characterized by scanning electron microscopy (SEM), grazing incidence X-ray diffraction (GID), and atomic force microscopy (AFM). The corrosion behaviour in Hank’s solution at room temperature was studied using a potentiodynamic polarization technique. The electrochemical measurements showed a high corrosion resistance of 316L-SS coated by both types of ceramic film. The best behaviour was presented by the alumina coating. The morphologies of the corroded films showed that the alumina and zirconia films presented low damage with little pitting corrosion compared with the uncoated 316L-SS.

Abstract: The microstructure of FeAl40 intermetallic alloy produced by spray atomization and deposition, with boron additions and reinforced with Al2O3 particles was studied. This technique allowed the co-deposition of particulate reinforcement and the addition of boron in order to obtain a boron concentration of 0.4 at. %. The additions of alumina particles produce a grain refinement. High resolution transmission electron microscopy observations shows a precipitation of boron in the FeAl matrix in despite of the rapid solidification process. Fe3B precipitates were found which is a metastable phase formed during the rapid solidification process. In addition, FeB precipitates were observed.