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The escalating demand for advanced structural materials with superior wear and corrosion resistance in aeronautical and military applications has spurred interest in amorphous alloys, particularly metallic glasses, due to their non-crystalline atomic configurations and exceptional mechanical properties. High-Velocity Oxygen Fuel (HVOF) spraying, a high-performance thermal spray technology, has emerged as a robust solution for enhancing the surface integrity of these materials by delivering dense, well-bonded coatings. This study investigates the integration of HVOF in reinforcing amorphous materials, with a specific focus on augmenting wear resistance under extreme mechanical stresses and improving corrosion protection in hostile environments. Key parameters such as particle velocity, flame temperature, and spray distance are analyzed to optimize coating quality while preserving the amorphous phase. The article delves into the microstructural evolution during deposition, assessing the resultant performance improvements through empirical data and computational models. Findings indicate that HVOF reinforcement significantly enhances the operational longevity of amorphous materials, positioning them as viable candidates for high-stress, corrosive conditions in military aviation, defense systems, and aerospace components. [ABSTRACT FROM AUTHOR]

This paper highlights the changes of polyethylene behaviour during various loading rates as well as the influence of test temperature on the material characteristics. Passive infrared thermography method and a high speed infrared camera were used to observe the temperature changes of the sample surface during the tests. The experimental program was carried out on samples taken from PE80 polyethylene gas pipes with simulated imperfections with bilateral V-notch, U-notch, and central hole. Samples have been tensile tested and the results are correlated with the temperature distribution of the samples surface. [ABSTRACT FROM AUTHOR]

The heat generated during friction stir welding process depends on plastic deformation of the material and friction between the tool and the material. In this work, heat generation is analysed with respect to the material velocity around the tool in Al alloy Al2024-T351 plate. The slip rate of the tool relative to the workpiece material is related to the frictional heat generated. The material velocity, on the other hand, is related to the heat generated by plastic deformation. During the welding process, the slippage is the most pronounced on the front part of the tool shoulder. Also, it is higher on the retreating side than on the advancing side. Slip rate in the zone around the tool pin has very low values, almost negligible. In this zone, the heat generation from friction is very low, because the material is in paste-like state and subjected to intensive plastic deformation. The material flow velocity around the pin is higher in the zone around the root of the pin. In the radial direction, this quantity increases from the pin to the periphery of the tool shoulder. [ABSTRACT FROM AUTHOR]

The use of graphene (Gr) and its derivates graphene oxide (GO) showed that these materials are good candidates to enhance the properties of polyurethane (PU) coatings, especially the anticorrosion ones since graphene absorbs most of the light and provides hydrophobicity for repelling water. An important aspect of these multifunctional materials is that all these improvements can be realized even at very low filler loadings in the polymer matrix. In this work, an ultrasound cavitation technique was used for the proper dispersion of GO nanosheets (GON) in polyurethane (PU) resin to obtain a composite coating to protect the AlMg3 substrate. The addition of GON considerably improved the physical properties of coatings, as demonstrated by electrochemical impedance spectroscopy (EIS) analysis, promising improved anticorrosion performance after accelerated UV-ageing. Computational methods and Differential Scanning Calorimetry (DSC) measurements showed that GON facilitates the formation of additional bonds and stabilizes the PU structures during the ultraviolet (UV) exposure and aggressive attack of corrosive species. Limiting oxygen index (LOI) data reveal a slow burning behaviour of PU-GON coatings during UV exposure, which is better than PU alone. [ABSTRACT FROM AUTHOR]

Experimental measurement and analytical calculation of preheating, i. e. interpass temperature during multi-pass repair welding has been presented. Analytical calculation is based on heat transfer analysis, whereas measurements have been performed by thermovision camera. Repair welding was performed on crane wheels in the Steelworks Smederevo. Comparison of results indicated that analytical calculation is good enough as the first approximation, but it needs further elaboration, e. g. taking into account the radiation component of heat dissipation and/or temperature dependence of material thermomechanicalproperties. [ABSTRACT FROM AUTHOR]

Disseminated intravascular coagulation (DIC) represents a major challenge in obstetrics. The prognosis is influenced by the severity of the coagulopathy and its underlying condition. Early recognition of DIC, if possible, is important because of the potential for end-organ microvascular thrombosis and/or major blood loss. Obstetric DIC manifests mainly with bleeding. In order to facilitate the diagnosis and management of disseminated intravascular coagulation, a pregnancy-specific DIC score was developed. The therapy aims at treating the condition that triggers DIC, the hemorrhagic complications and the coagulopathy. [ABSTRACT FROM AUTHOR]

The purpose of this research is to meet current technical and ecological challenges by developing novel steel coating systems specifically designed for mechanical equipment used in aggressive acid conditions. Homogeneous sandwich-type layered films on the surface of steel electrodes were realized using a pseudo-binary oxide, MnTa2O6, and two different substituted porphyrin derivatives, namely: 5-(4-carboxy-phenyl)-10,15,20-tris (4-methyl-phenyl)-porphyrin and 5-(4-methyl-benzoate)-10,15,20-tris (4-methyl-phenyl)-porphyrin, which are novel investigated compound pairs. Two suitable laser strategies, pulsed laser deposition (PLD) and matrix-assisted pulsed laser evaporation (MAPLE), were applied in order to prevent porphyrin decomposition and to create smooth layers with low porosity that are extremely adherent to the surface of steel. The electrochemical measurements of corrosion-resistant coating performance revealed that in all cases in which the steel electrodes were protected, a significant value of corrosion inhibition efficiency was found, ranging from 65.6 to 83.7%, depending on the nature of the porphyrin and its position in the sandwich layer. The highest value (83.7%) was obtained for the MAPLE/PLD laser deposition of 5-(4-carboxy-phenyl)-10,15,20-tris (4-methyl-phenyl)-porphyrin/MnTa2O6(h), meaning that the inhibitors adsorbed and blocked the access of the acid to the active sites of the steel electrodes. [ABSTRACT FROM AUTHOR]