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Ti6Al4V alloy forms an oxide layer on the Surface and is metallic material used as a biomaterial. The investigation determined the level lof wear of corrosion of the alloy fabricated by additive manufacturing as in the titanium specimen made by forge subjected to anodizing. The use of NaOH (0.1M) and H2SO4 (1M) was defined as electrolytes, with a time of 5 minutes, a voltage of 20 and 40V, wear tests on Pin on Disk and corrosion resistance in Hank solution. Evidencing the usefulness of anodizing on the surface of titanium. The voltage of the 40V produces a uniform oxide layer with greater thickness, decreasing the level of wear and corrosion rate. The right electrolyte is H2SO4 as NaOH produces more corrosion. Forging specimen has higher corrosion resistance than alloy made by additive manufacturing.

The hydrocarbon transportation industry uses extensive pipeline networks subject to complex loading conditions. The finite element analysis (FEA) has proven to be effective in simulating the deformation behavior in these pipelines, which assists in the assessment of their integrity and risks.  In this work, a model developed using finite elements is proposed to analyze the behavior of API 5L Gr B carbon steel pipes, subject to internal pressure and lateral loads. The model is validated through uniaxial tensile and four-point bending tests. In addition, parametric analysis is carried out considering variables such as diameter, lateral load, and distance between supports. The objective is to identify which one of these variables has the most influence in the unit strain.  The results indicate that the unit strain obtained from the numerical model agrees with the experimental tests. Furthermore, it is concluded that the diameter is the influential parameter.

Engine oil is one of the key elements to protect and to increase the life of the lubricated engine parts. However, it gets contaminated by external particles either in filtration or during combustion, which produces deterioration in some of the engine parts which are being lubricated. In that sense, delays and very expensive repairs are generated at the maintenance workshops due to the high contamination in oils and to the late detection of the deteriorated parts. This work presents an analysis of used oils, extracted from hot and cold engines of 2.5-liter engine pick-up trucks, by using the two methods of the X-ray fluorescence technique (XRF): standard-less and calibrated, in order to determine the elements present and to establish the engine parts that wear out more easily and thus, to help with predictive maintenance of the trucks. The results are also useful for comparison purposes and to evaluate the effectiveness of the XRF technique in analyzing these types of samples.

A full-factorial 33 experiment was used in this study to determine the optimal values of the tensile properties of three composite materials manufactured based on three polymeric resins: Derakane Momentum epoxy vinyl ester based on bisphenol-A (DM-411), polyester based on terephthalic acid (P115-A), and isophthalic polyester (P2000). Such materials were reinforced with magnetite powders at concentrations of 10, 20, and 30 wt %, and the particle sizes were classified with three sieves: #200 (46–75 μm), #325 (26–45 μm), and #500 (0–25 μm). The compounds were manufactured using the hand lay-up method at room temperature in accordance with ASTM D638-14 for M1-type specimens. A tensile test was conducted on a universal Microtest EM2/300/FR machine at a test speed of 5 ± 25 % mm/min using an Epsilon extensometer calibrated in accordance with the ASTM E83 standard at 20 ± 2 °C. The magnetite powders and compound morphology were studied by Scanning Electron Microscopy. The mechanical properties of the compounds and the optimal response found by Analysis of Variance (ANOVA) and Response Surface Methodology (RSM) are also reported. The best response to the mechanical stimuli occurs with the composite material prepared with the epoxy vinyl ester resin DM-411, a concentration of 29.4 % of magnetite (Fe3O4), a particle size of 58.5 microns, and a 200 sieve.

In this study, we report the thermophysical properties (at room temperature) and the morphology of a composite with a polyester resin matrix and magnetite filler powders (Fe3O4), conformed in three configurations: randomly dispersed particles, particles oriented parallel to a constant 300 mT magnetic field, and particles oriented perpendicular to a constant 300 mT magnetic field. Samples were formed by hand lay-up with weight percentages of 10, 20 and 30%, where the highest concentration corresponds to the resin. The thermophysical properties were determined using the KD2 Pro® system, which uses the physical principle of linear transient heat flow, for which the dual sensor SH-1 was used. The morphology and microanalysis were studied using a scanning electron microscope (SEM, FEI Quanta 650 FEG). It was observed from the morphology that the magnetite particles are oriented in the direction of the magnetic field lines during the process of resin curing. It was also perceived that the values of the thermophysical properties found experimentally are within the limits (upper and lower) of Hashin and Shtrikman and that those values increase when the magnetite concentration increases in the sample. No significant difference was observed in the thermal properties because of the magnetic field applied.

Water pollution caused by heavy metals represents a critical global concern due to its harmful effects on human health and aquatic ecosystems. Ion adsorption membranes have emerged as effective solutions for water decontamination. Accordingly, this study provides a physicochemical evaluation of a magnetic polymeric membrane designed for the adsorption of copper ions (Cu²⁺), fabricated via electrospinning. The membrane consists of a polyvinylidene fluoride (PVDF) and polystyrene (PS) polymeric matrix embedded with magnetite (Fe₃O₄) nanoparticles (NPs) functionalized using ethylenediaminetetraacetic acid (EDTA). Morphological characterization through scanning electron microscopy (SEM) indicated fiber diameters averaging approximately 3 µm. Fourier-transform infrared spectroscopy (FTIR) confirmed successful functionalization with EDTA as a chelating agent. Adsorption data fitted to the Langmuir isotherm model indicated a maximum adsorption capacity of 25.1 mg g⁻¹ for the PVDF/PS@Fe₃O₄-EDTA polymeric membrane. Magnetic characterization revealed superparamagnetic and ferromagnetic properties. Overall, the membrane demonstrated proficient adsorption of copper ions due to available functional adsorption sites and the incorporation of magnetic nanoparticles.

Titanium alloys, particularly Ti6Al4V, are widely used in biomedical applications due to their excellent mechanical properties and inherent biocompatibility. However, enhancing their surface characteristics, such as biocompatibility and corrosion resistance, remains a key challenge for their long-term use in medical implants. In this study, we investigate the effects of rhenium–carbon coatings deposited on Ti6Al4V substrates via magnetron sputtering, incorporating a molybdenum anchoring layer. X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) analyses confirmed the formation of rhenium carbides, elemental rhenium, and rhenium oxides within the coatings. Despite these successful depositions, scanning electron microscopy (SEM) revealed significant delamination and poor adhesion of the coatings to the Ti6Al4V substrates. Corrosion resistance, evaluated through potentiodynamic polarization tests, showed an increase in corrosion current densities and more negative corrosion potentials, indicating a detrimental effect on the substrate’s corrosion resistance. Biocompatibility assessments using PK15 cells demonstrated a marked decrease in cell viability and metabolic activity, particularly in samples with higher surface roughness. These findings underscore the critical need for the optimization of surface preparation and deposition processes to improve both the adhesion and biocompatibility of rhenium–carbon coatings on Ti6Al4V substrates. Future research should aim to refine coating technique to enhance adhesion, explore the mechanisms of cytotoxicity related to surface roughness, and expand biocompatibility studies across different cell lines and biological environments.

Powder metallurgical steels have lower corrosion resistance compared to wrought steels. Their behavior Is simultaneously affected by Interconnected porosity, pore morphology, Interaction with sintering atmospheres, and metallurgical phenomena such as steel 'sensitization'. This work presents the theoretical methodology to calculate the optimum composition of the mixture and the conditions for a maximum packing of two sizes spheres (assuming a spherical shape factor) according to the development published by Brouwers for a system of binary mixtures. For the theoretical determination of the mixture, the results of density and porosity of a 316 powder metallurgical stainless steel made from prealloyed powders of two average granulometries (45µm and 150µm) are presented. The powders were combined in different proportions to define the appropriate quantities that allow the manufacture of steel with a low corrosion rate. The obtained results confirm that the theoretical calculation is a reliable alternative to formulate powder metallurgical alloys since good particle packing is achieved, which has a favorable effect on the characteristics of the finished product.

Los aceros pulvimetalúrgicos tienen una menor resistencia a la corrosión en comparación con los aceros forjados. Su comportamiento se ve afectado simultáneamente por la porosidad interconectada, la morfología de los poros, la interacción con las atmósferas de sinterización y fenómenos metalúrgicos como la \"sensitización\" del acero. Este trabajo presenta la metodología teórica para calcular la composición óptima de una mezcla y las condiciones requeridas para obtener un empaquetamiento máximo de esferas de dos tamaños promedio de partículas (asumiendo un factor de forma esférico) según la investigación publicada por Brouwers para un sistema de mezclas binarias. Para la determinación teórica de la mezcla se presentan los resultados de densidad y porosidad de un acero inoxidable pulvimetalúrgico 316 elaborado a partir de polvos prealeados de dos granulometrías promedio (45μm y 150μm). Los polvos se combinaron en diferentes proporciones, con el fin de definir las cantidades adecuadas que permitan fabricar un acero con bajos valores de su velocidad de corrosión. Los resultados obtenidos confirman que el cálculo teórico es una alternativa confiable para formular aleaciones pulvimetalúrgicas, ya que se logra un alto empaquetamiento de partículas, lo cual incide favorablemente en las características del producto terminado.

Engine oil is one of the key elements to protect and to increase the life of the lubricated engine parts. However, it gets contaminated by external particles either in fltration or during combustion, which produces deterioration in some of the engine parts which are being lubricated. In that sense, delays and very expensive repairs are generated at the maintenance workshops due to the high contamination in oils and to the late detection of the deteriorated parts. This work presents an analysis of used oils, extracted from hot and cold engines of 2.5-liter engine pick-up trucks, by using the two methods of the X-ray fuorescence technique (XRF): standard-less and calibrated, in order to determine the elements present and to establish the engine parts that wear out more easily and thus, to help with predictive maintenance of the trucks. The results are also useful for comparison purposes and to evaluate the effectiveness of the XRF technique in analyzing these types of samples.