The objective of this study is to evaluate the effect of adding water at different concentrations (0.5%, 5% and 10%) in ethanol-95% gasoline and 85% (% V) of ethanol in addition to a white medium on the Corrosion Under Stress (CBT) for API 5L X52 steel, typically used in the transportation of hydrocarbons. The tests were performed at a constant rate of extension in a CERT machine at a nominal strain rate of 10-6 s-1. CERT test of simultaneous manner, using the technique of monitoring Electrochemical Noise potential noise and current noise wherein the fluctuations have correspondence with the dissolution of the material. Additionally, it is noted that evidence less in% (V) of the water present is less effective and secondary cracks in the samples analyzed for CBT test results cyclic polarization curves show no tendency to SCC.

The alternative use of ethanol as a biofuel, or total or partial substitute for fossil fuels, has a significant effect when blend with ethanol-gasoline, this addition of gasoline increases the octane number and reduces CO2 emissions from cars. In this study, water concentrations (0.5 and 5%) were used in 10, 85 and 95% (% V) ethanol blends, using the electrochemical linear polarization resistance (LPR) technique in steel pipe API-5L X52. As complementary techniques, pH and conductivity were monitored before and after each test. The objective of this research is to measure the effect of water on the corrosion rate of the ethanol blends. As a result, it was obtained that the solutions with higher water concentration had the highest value of corrosion rate, as well as localized corrosion damage in both cases, which was corroborated by scanning electron microscopy (SEM).

CIATEQ, A.C.), Procesos de Manufactura Av. Manantiales 23-A, Parque Industrial Bernardo Quintana. El Marqués, Querétaro.México.In the aircraft and aerospace industry, coatings obtained by thermal spraying HVOF are use in some components of steam turbines, due to the passage of gases at high temperatures cause of the rotation of the wing which is subjected to severe static and dynamic load, usually associated with microstructure degradation mechanisms as corrosion, wear and creep. The MCrAlY coating (M = Co or Ni) type applications are used to provide wear and also corrosion resistance. In this work a HVOF gun was used to prepare a MCrAlY coating which has been subjected to two electrochemical techniques: polarization resistance and cyclic polarization curves in order to obtain the behavior of the rate of corrosion in acid and neutral media. The results show that the acid factor in the solution play an important role in the corrosion resistance of MCrAlY coating applied by HVOF thermal spraying.

Metal coatings 59Ni 21Cr 13Mo 4Fe 3W by laser ablation, treatment is performed with a laser NdYag a wavelength of 1064nm for impinging the beam in a metal sample alloy mentioned evaluated, the particles are detached from said target attached in layers to the substrate surface (steel T22 and 4140) previously treated so that a coating is formed to improve the corrosion behavior. This deposition technique has the advantage of minimizing the porosity in the coating providing a more uniform surface coatings by thermal spraying (HVOF) and plasma, for application in diverse areas of industry turbo machinery such as, boilers, oil refineries, heat recovery, aeronautics, etc.

Nickel base superalloys have been widely used for manufacturing key structural materials for aircraft engine blades. These alloys are developed to withstand the most deleterious degradation mechanisms as creep damage, fatigue, loss of thermal stability and environmental attacks as oxidation and hot corrosion during service. The damages can compromise the structural integrity of the aircraft and in the next generation of advanced engines they will require even higher gas temperature. Consequently, much work has been done in order to develop protective approaches that will increase component lifetimes and meet the development of advanced gas turbine engines. One of such is the used of thermal barrier coatings (TBCs). Thus the aim of the present investigation is to study the electrochemical behavior of YSZ coatings deposited by physical vapor deposition (PVD) on an aeronautical nickel based superalloy to improve the oxidation resistance. The electrochemical techniques conducted on Incoloy 800HT substrates, show that the corrosion velocity decreased with the YSZ coating system.