The study and improvement of the corrosion resistance of materials used in concentrated solar power plants is a permanent field of research. This involves determining their chemical stability when in contact with heat transfer fluids, such as molten nitrate salts. Various studies indicate an improvement in the corrosion resistance of iron-based alloys with the incorporation of elements that show high reactivity and solubility in molten nitrate salts, such as Cr and Mo. This study analyzes the kinetic and thermodynamic aspects of the beginning of the corrosion process of ferritic steels immersed in Solar Salt at 400, 500, and 600 °C. The analysis of the kinetic data using the Arrhenius equation and the Transition State Theory shows that an increase in the Cr/Mo ratio reduces the activation energy, the standard formation enthalpy, and the standard formation entropy. This indicates that its incorporation favors the degradation of steel; however, the results show a reduction in the corrosion rate. This effect is possible due to a synergistic effect by the formation of insoluble Fe-oxide layers that favor the formation of a Cr oxide layer at the Fe-oxide-metal interface, which limits the subsequent oxidation of Fe.

In this paper, the electrochemical performance of the NiAl intermetallic immersed in the 60% NaNO₃-40% KNO₃ (wt%) eutectic mixture, also known as Solar Salt, is reported. Mass loss measurements and electrochemical tests evaluate its behavior at different temperatures (300, 400, and 500 °C). Mass loss measurements are performed over 1000 h, and electrochemical tests over 100 h. The mass loss results show that the Ni₃Al intermetallic exhibits excellent corrosion resistance under the test conditions. Electrochemical measurements confirm the excellent performance of the Ni₃Al intermetallic in molten solar salt in the test temperature range. Experimental observations show that increasing temperature decreases the corrosion resistance of the intermetallic and favors the formation of protective layers of the Al₂O₃ and NaAlO₂ types.

The high-temperature corrosion behavior of A1, T22, and T91 steels was investigated in molten nitrate salts at 400, 500, and 600 °C during 100 h of exposure. The combined influence of temperature and chromium content on corrosion kinetics and oxide-scale stability was evaluated using open-circuit potential (OCP), linear polarization resistance (Rp), electrochemical impedance spectroscopy (EIS), scanning electron microscopy, X-ray diffraction, and cross-sectional elemental mapping. OCP measurements showed a progressive shift toward more negative potential with increasing temperature, indicating enhanced oxidation tendency. Electrochemical measurements revealed a systematic decrease in Rp and impedance magnitude as temperature increased, confirming accelerated corrosion kinetics and reduced interfacial resistance. EIS spectra exhibited two characteristic time constants associated with the outer corrosion products and the inner metal/oxide interface. Significant differences in scale growth were observed depending on alloy composition. At 600 °C, oxide thickness reached approximately 700–800 μm for A1, ~100 μm for T22, and ~10 μm for T91. Chromium-containing steels promoted the formation of a compact Cr-rich inner oxide layer that improved scale adhesion and suppressed the exfoliation phenomena observed in A1 steel. Overall, temperature controls corrosion kinetics, whereas chromium content governs oxide-scale compactness and long-term stability in molten nitrate environments.

This study investigates the effect of copper (Cu) and silver (Ag) additions on the electrochemical behavior of the Fe40Al intermetallic alloy in artificial saliva, aiming to evaluate its potential for biomedical applications such as dental implants. Alloys with varying concentrations of Ag (0.5, 1.0, and 3.0 wt%) and Cu (1.0, 3.0, and 5.0 wt%) were synthesized and exposed to a biomimetic electrolyte simulating oral conditions. Electrochemical techniques, including open circuit potential (OCP), linear polarization resistance (LPR), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS), were employed to assess corrosion performance. Results show that unmodified Fe40Al exhibits good corrosion resistance, attributed to the formation of a stable passive oxide layer. The addition of Cu, particularly at 3.0 wt%, significantly improved corrosion resistance, yielding lower corrosion current densities and higher polarization resistance and charge transfer resistance values, surpassing even 316L stainless steel in some metrics. Conversely, Ag additions led to a degradation of corrosion resistance, especially at 3.0 wt%, due to microstructural changes and the formation of metallic Ag precipitates, AgSCN, and galvanic cells, which promoted localized corrosion. EIS results revealed that Cu- and Ag-modified alloys developed less homogeneous and less protective passive layers over time, as indicated by increased double-layer capacitance (C_dl) and reduced constant phase element exponent (n_dl) values. Overall, the Fe40Al alloy shows intrinsic corrosion resistance in simulated physiological environments, and Cu additions can enhance this performance under controlled conditions. However, Ag additions negatively affect the protective behavior of the passive layer. These findings offer critical insight into the design of Fe-Al-based biomaterials for dental or biomedical applications where corrosion resistance and electrochemical stability are paramount.

El acceso al agua potable de calidad es fundamental para la salud pública. Este estudio evalúa la calidad del agua en Bacerac, Sonora, considerando su variabilidad estacional y cumplimiento con la NOM-127-SSA1-2021. Se realizó un muestreo durante un año en distintos puntos de abastecimiento, analizando parámetros fisicoquímicos, microbiológicos y elementos potencialmente tóxicos (EPT). Los resultados indican que el 39.28 % de las muestras presentó un pH fuera del rango permisible (6.5-8.5), mientras que el 37.5 % mostró una dureza superior a 500 ppm como CaCO₃, lo que afecta su potabilidad y uso doméstico. La contaminación microbiológica fue evidente en el 62.5 y 16.07 % de las muestras, donde se detectaron coliformes totales y fecales, respectivamente. A pesar de que las concentraciones de arsénico y plomo estuvieron por debajo de los límites normativos, su detección sugiere un riesgo potencial debido a la exposición crónica. Un hallazgo crítico fue la ausencia de cloro residual libre en todas las muestras; ello indica la falta de desinfección en el sistema de distribución y aumenta el riesgo sanitario. Ante tal situación, se recomienda la implementación de medidas correctivas, como la instalación de sistemas de tratamiento y monitoreo continuo. Este estudio resalta la necesidad de una gestión integral del recurso hídrico para garantizar su calidad y proteger la salud de la población.

El acceso a agua potable de calidad es fundamental para la salud pública. Este estudio evalúa la calidad del agua en Bacerac, Sonora, considerando su variabilidad estacional y cumplimiento con la NOM-127-SSA1-2021. Se realizó un muestreo durante un año en distintos puntos de abastecimiento, analizando parámetros fisicoquímicos, microbiológicos y elementos potencialmente tóxicos (EPT). Los resultados indican que el 39.28% de las muestras presentaron un pH fuera del rango permisible (6.5-8.5), mientras que el 37.5% mostraron una dureza superior a 500 ppm como CaCO₃, lo que afecta su potabilidad y uso doméstico. La contaminación microbiológica fue evidente en el 62.5% y 16.07% de las muestras, donde se detectaron coliformes totales y fecales, respectivamente. A pesar de que las concentraciones de arsénico y plomo estuvieron por debajo de los límites normativos, su detección sugiere un riesgo potencial debido a la exposición crónica. Un hallazgo crítico fue la ausencia de cloro residual libre en todas las muestras, lo que indica la falta de desinfección en el sistema de distribución y aumenta el riesgo sanitario. Ante esta situación, se recomienda la implementación de medidas correctivas, como la instalación de sistemas de tratamiento y monitoreo continuo. Este estudio resalta la necesidad de una gestión integral del recurso hídrico para garantizar su calidad y proteger la salud de la población.