The effect of boron additions on the densification of a ferritic stainless steel during sintering was studied. Experimental results showed that density and microstructure changed with the boron content. Boron promotes the formation of a liquid phase, which resulted from a eutectic reaction involving iron and chromium. The presence of the liquid phase modified the microstructure morphology, shape of porosity, density, and hardness.

In the last decades, there have been many researches on the use of ethanol as biofuel, detecting corrosion processes in storage systems, including systems in bioethanol-gasoline blends. This research analyzes the phenomena that occur when exposing the API 5L X-52 steel under stress conditions and presenting the analysis to the susceptibility of the Stress Corrosion Cracking (SCC). The preparation of the test specimens was carried out under the NACE standard TM0177-05, with the results obtained and using the McIntyre diagram the susceptibility of the steel to the SCC was determined; depending on the ductility parameters. The type of fault present in each specimen was identified by Scanning Electron Microscopy (SEM). Under the experimental conditions of the present work, it has concluded that the API 5L-X52 steel exposed in the different study means is not susceptible to Stress Corrosion Cracking.

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The objective of this research is to evaluate the susceptibility of stress corrosion cracking (SCC) to the effect of adding water in different concentrations of 0.5, 5 and 10% in ethanol-gasoline blends up to 95 and 85% of ethanol, in addition to an inert media for API 5L-X52 steel, commonly used in the transport of hydrocarbons, by constant extension rate test (CERT). Extension rate range was 10-6 s-1, simultaneously, the potential and current noise were examined by the Electrochemical Noise technique where the registered fluctuations have correspondence with the dissolution of the material. Additionally, it was observed that tests with low content in % (V) of water present the less satisfactory results, as well as secondary cracks in the samples analyzed by SCC.

The interest in terms of fuels who are based on ethanol, as a total or partial substitute for fossil fuels. In this research, three concentrations of water (0.5, 5 and 10%) by volume were evaluated, in ethanol-gasoline blends at 95% by volume of ethanol, using cyclic polarization curves (CPC) on API-5L X52. As a complementary technique, weight loss (WL) was monitored with exposures of 30, 60 and 90 days of immersion. The objective of this investigation is to determine the mechanism of corrosion and the measurement of the effect of the water related to the WL of steel, regardless to the ethanolic mixtures. The result obtained from the mass loss was increased when the water concentration was less than 5% by volume. The CPC showed that blends with low water content there is a tendency to the formation of corrosion by pitting, which was corroborated by scanning electron microscope (SEM).