Abstract AISI D6 tool steel and AISI 304 stainless steel are among the most widely used material in the industry. However, this application field can still be expanded through the coatings deposition. In this regard, the objective of this work was to evaluate the impact of coatings application by cathodic cage technique using Hastelloy’s cathodic cage, on corrosion resistance of these steels. Two treatment temperatures were compared. The samples were characterized by Optical Microscopy, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, X-Ray Diffraction with the application of the Rietveld routine and corrosion test. The results showed the formation of multiphase layers that contributed to corrosion potentials reduction for treatments at 400 °C, being more effective when applied on AISI D6. It was observed that the corrosion resistance is influenced by the temperature, which was attributed to the precipitation of chromium nitride and iron oxide at 450 ºC.

AbstractPolyester fabric samples – PET (poly (ethylene terephtalate)), were treated with oxygen plasma, in order to alter the hydrophilicity of such material. The process parameters: working pressure, current, tension and temperature were kept constant, varying only the treatment time. In order to evaluate the change caused on samples hydrophilicity, as well as the influence of the treatment time, the vertical wicking test was used. The samples were stored at standard temperature and pressure conditions, and their wettability were measured one day after the treatment and repeated after 30, 60 and 360 days, in order to check the stability of the effects produced. Scanning electron microscopy (SEM), Raman and ATR (Attenuated total reflection) spectroscopies were used to evaluate physical and chemical alterations on the samples surface. The results have shown a substantial improvement on the hydrophilicity of the treated samples compared to the non-treated sample.

Thin nitride and titanium dioxide films were produced using an innovative technique called cathodic cage depositon. Uniformity, three-dimensionality and high rate deposition are some of the advantages of this technique. In this study we discuss the influences of temperature, treatment time and gaseous atmosphere on the characteristics of the deposited films. The TiN (titanium nitride) and TiO2 (titanium dioxide) films were produced using a high deposition rate of 2,5 µm/h at a work temperature and pressure of 400°C and 150 Pa respectively. EDS technique was used to identify the chemical composition of the thin film deposited, whilst Raman spectroscopy indicated the phases present confirmed by DRX analysis. The thickness of the deposited films was studied using electron microscopy scanning. The results based on the deposition parameters confirm the great efficiency and versatility of this technique, which allows a uniform three-dimensional film deposition on any material without the appearance of stress. Compared to other techniques, cathodic cage deposition enables deposition at lower temperatures and higher pressures.