In this study, aluminum alloy 7075 (AA7075) nanopowders were prepared by High-Energy Ball Milling (HEBM) in a bath of isopropyl alcohol. The process was investigated in different milling times and silicon carbides (SiC) reinforcement percentual. The effects of these parameters on the samples were characterized by X-ray diffraction (XRD), Laser Diffraction (LD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). The XRD analyses showed that as the grinding time increases, the micro deformation also increases, while the crystallite and particle size decrease until a constant value at 480 min. If the percentual of SiC reinforcement increases until 5 percent, there is a minimum change in the results compared to AA 7075 milling 480 min with no reinforcement. On the other hand, when the AA7075 was milled for 480 min and reinforced by 10 percent SiC, the best structural refinement result was achieved.

In this work, composite powders of aluminum alloy 7075 (AA7075) reinforced by 2 weight percent of nanosized particles of silicon carbide (SiC), titanium nitride (TiN), and zinc oxide (ZnO) were produced in a bath of isopropyl alcohol by high energy ball milling during 480 min at 25 ºC, 900 rpm, and Balls-to-Powder Weight Ratio (BPR) of 20:1. The techniques of X-Ray Diffraction (XRD), Laser Diffraction Method (LDM), Scanning Electron Microscopy (SEM), and microanalysis of Energy Dispersive Spectroscopy (EDS) were used to characterize the powders as received and processed. Then, the composites were hot extruded and characterized by XRD, SEM, and microhardness Vickers (HV). The milling process reduces the crystallite and particle size to around 30 nm and 10 µm, respectively. After extrusion, a fine microstructure and good consolidation were found for all bars, except for AA7075 as received. The ranging microhardness values were from 97 HV to 121 HV.

This paper sets out to evaluate the corrosion of ASTM A131 grade A36 carbon steel exposed to a diesel oil S10 / saline water system and the biodegradation of diesel oil S10 to simulate storage, transport and fuel use systems during a period of 30 days. The corrosion process was investigated through electrochemical tests of Open Circuit Potential (OCP), Electrochemical Impedance Spectroscopy (EIS) and Linear Polarization (LP). The morphology of the corrosion products were analyzed by Scanning Electron Microscopy (SEM). The results showed that the presence of saline water in the system containing diesel oil is an aggravating factor which promotes the biodegradation of the fuel and, consequently, aggravates the corrosion process.

High-strength low-alloy steel is used in pipelines, which transport oil/gas and also produced water in the process of the secondary recovery of oil. This paper investigates the corrosion of X80 steel after immersion in static systems (biotic and abiotic). The corrosion rate, the corrosion morphology and the hardness of the coupons were investigated. The corrosion products were determined by SEM/EDS and XRD. The corrosion rates of the coupons in the biotic system were moderate and had an agressive pit morphology, while those of the coupons in the abiotic system were low with less aggressive pit. The hardness of the coupons after exposure to the systems of produced water was not changed compared with that of the control coupons. The corrosion products formed in the biotic system were Fe(OH)3, Fe(OH)2, FeOOH, Fe3O4, FeS2, FeCl3, and in the abiotic system, NaCl, CaCl2 and SrSO4. BaSO4 and CaCO3 were identified in both systems.

This paper sets out to evaluate the corrosion and biocorrosion of carbon steel ASTM A283 exposed to a Diesel S10 oil/tap water system under static conditions for 90 days. The following analyzes were performed: physico-chemical in tap water, sulfur content in Diesel S10 and quantification of sessile microorganisms in the biofilm formed on the metal. To monitor the corrosion process, mass loss, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), confocal laser microscopy and X-ray diffraction (XRD) were performed. There were changes in the composition of the medium, correlated with the formation of corrosion and biofilm products. There was biodegradation of the fuel, which in contact with water influenced the development of microorganisms. Moreover, the corrosion rate was classified as moderate, the main form of corrosion being seen to be local alveolar corrosion. Therefore, the results revealed that water in diesel oil can be an aggravating factor in the process of corrosion and biocorrosion.