The catalytic electrolysis of water enables this process to be performed at low over-potential, and therefore at a lower energy expenditure.Materials like Ni, Mo or W could substitute costly Pt in this role, especially when applied in the form of coatings.Experiments conducted to date have shown that the efficiency of electrolysis is still increasing in the case of metal nano-rods separated by carbon sheets.The present work is aimed at assessing the temperature stability of such a coating obtained by the magnetron sputtering of an AISI 316L (Fe69Cr18Ni11Mo2, in wt%) target in an atmosphere of Ar and C 2 H 2 .The use of in-situ TEM (transmission electron microscopy) heating allowed the start of crystallization of the so-produced coating to be determined, which occurred at ~400.Isothermal annealing at this temperature for 1 hour resulted in the predominant precipitation of -Fe in parallel with a smaller amount of Ni, Fe, C rich nano-particles, while Cr was distributed relatively uniformly throughout the whole coating.Simultaneously, the amorphous carbon underwent transformation to graphite.The experiment showed that the amorphous metalcarbon composite coatings developed for the hydrogen evolution reaction (HER) may be liable to crystallize in the case it was used in the catalytic electrolysis of superheated steam.

This paper presents a technological sequence of the fabrication process and test results of composite coatings with a nanocrystalline copper matrix including a dispersion phase in the form of graphene flakes deposited by electrochemical reduction on electrical equipment components.The conducted research included the development of solution compositions and process parameters for the deposition of Cu/graphene composite coatings, in addition to adaptation of the coating deposition process to a larger scale on a pilot electroplating line.The innovative aspect presented in the work (a key challenge) was the transfer of the positive results of the work from the laboratory scale to the semi-technical scale.The described work involved running the process in a plating drum and on hangers on a pilot plating line.The surface morphology, and roughness and the structure of the produced composite coatings were characterized.The thickness and bonding of the produced coatings to the substrate material were evaluated.Hardness tests of the produced coatings were carried out.The properties of the Cu/graphene composite coatings produced on the hangers and in the electroplating drum on the pilot electroplating line were compared.The key research challenge was the development of a technology for the fabrication of composite coatings on electrical equipment components, involving the application of Cu/graphene composite coatings by electroplating techniques at on a laboratory scale and then transferring the work to the pilot electroplating line.

In this work, Al5052 alloy was reinforced with varying weight percentages of titanium diboride (TiB) and zirconium dioxide (ZrO) to fabricate three hybrid composite samples (S1, S2, and S3) via the stir casting process.Dry sliding wear tests were conducted using a pin-on-disc apparatus under varying loads (10, 20, and 30 N) and sliding speeds (300, 500, and 700 rpm), with a constant sliding distance of 1500 m.The results showed that the specific wear rate (SWR) grew with increasing load, reaching a maximum of 3.45 10 mm/Nm for sample S1 at 30 N. Among the samples, S3 exhibited the best wear resistance, with the lowest SWR of 1.35 10 mm/Nm under identical conditions.SEM analysis revealed different wear mechanisms such as mild ploughing in S1, crack formation in S2, and plastic deformation in S3.These findings demonstrate that the hybrid reinforcement of TiB and ZrO significantly improves the wear resistance of Al5052, making it suitable for applications in automotive and aerospace sectors requiring enhanced surface durability.

Substituting petrochemical plastics with biobased plastics from natural feedstock offers an environmentally friendly alternative to reduce the carbon footprint.Proteins are promising biopolymers that can be transformed into plastics and sourced from various types of biomass, such as microalgae.Microalgae, particularly spirulina, is considered an excellent renewable resource for bioplastic production due to its high protein content.This study focuses on the characterization of spirulina-polyethylene (PE) composites molded by compression molding technology.Both washed (for salt removal), and unwashed biomass were used in order to explore a potentially more sustainable and cost-effective option.Various loadings of both biomass types (5 % -30 % by weight) were investigated, and the mechanical (tensile, flexural, and impact resistance) as well as thermal properties (thermogravimetric analysis and differential scanning calorimetry) of the resulting composites were determined.The mechanical properties remained nearly unchanged compared to neat PE when the biomass content was kept under 10 wt.% for both the washed and unwashed biomass.At higher biomass loadings, a reduction in mechanical performance was observed; however, the molded parts maintained good aesthetics and acceptable properties.Despite the predictable adverse changes in thermal behavior, the processability of the materials was not affected.Differential scanning calorimetry indicated that total plasticization of the biomass protein was not achieved during the molding process.Additionally, no significant differences were found between the washed and unwashed biomass, suggesting that using unwashed biomass could be more economically and environmentally beneficial.

In this present research work, the electrical discharge machining (EDM) characteristics of an Al7010/2%B4C/2%BN (the reinforcement particles are taken as wt.%) hybrid metal matrix nanocomposite (HMMNC) are discussed. The effect of the EDM process variables like the discharge current (I), pulse on time (Pon), pulse off time (Poff) and gap voltage (Vg) on the response characteristics like the material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) are presented. The results revealed that the MRR, TWR, and SR grew with an increase in Ip and Pon. MRR, TWR, and SR increased with a rise in Poff up to 25 µs then declined. MRR, TWR, and SR decreased with an increment in gap voltage. The highest MRR was observed for a discharge current of 8 A, Pon of 60 µs, Poff of 25 µs and Vg of 30 V. SR and TWR were the smallest at Ip of 2 A, Pon of 15 µs, Poff of 55 µs and Vg of 60 V. The scanning electron microscope (SEM) micrographs of the machined surfaces revealed voids, craters and micro cracks.