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Summary MXene, which are known as two‐dimensional transition metal carbides have received heavy interest due to their rich elemental diversity and many fascinating physical and chemical properties. Here, Rh (0) nanoparticles deposited MXene catalysts were synthesized by an easy wet‐impregnation method for hydrogen production. Rh (0) nanoparticles were conveniently loaded on the surface of MXene (Rh/MXene) were used as an effective nanocatalyst for the hydrogen production from the hydrolysis of ammonia‐borane (AB). The morphological and structural characterizations of Rh/MXene catalysts show that Rh nanoparticles were successfully deposited on the surface of MXene substrates. Rh (0) nanoparticles with an average size of 2.55 nm were homogeneously dispersed and deposited on the MXene surface. The Rh/MXene displayed good catalytic performance in the hydrogen production via the hydrolysis of AB, and the turnover frequency value at 25°C was 288.4 min−1, which is comparable to most of the synthesized catalysts. The Rh/MXene catalyst displaying good activity in seven consecutive catalytic cycles can be considered a good nanocatalyst candidate for hydrogen production from the hydrolysis of AB.

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In this study, the effect of WC reinforcing particles on the microstructure and mechanical properties of CuAlMn and CuAlMn-WC alloy produced by powder metallurgy method was investigated by adding 5 %, 10 % and 15 % by volume WC to CuAlMn alloy. Cu, Al, Mn and WC powders of approximately 99.9 % purity with a grain size of 325 mesh were used in the production of the alloys. The samples were produced by hot pressing method at 900 ℃ temperatures under 35 MPa pressure for 6 minutes. Microstructure, phase formation, hardness and corrosion properties of the samples were investigated in detail. Scanning electron microscopy (SEM) was used for microstructure analysis and X-ray diffractogram (XRD) was used for phase formation detection. The hardness measurements of the samples were measured by microhardness measuring device. The corrosion tests were performed potentiodynamic polarization curves of the composite materials in 3.5% NaCl solution. As a result, it has been determined that the mechanical properties of WC reinforcing particles added to CuAlMn matrix increase with increasing volume ratio.

Production of magnesium alloy AM60 Powder by gas atomization method  The effect of gas pressure in powder production by gas atomization method  Powder characterization of magnesium alloy AM60 powder Figure A. Production process diagram and produced AM60 powder Purpose: In this study, AM60 magnesium alloy powder produced by gas atomization method is produced. As a result of the literature research, there is no study about the production of AM60 magnesium alloy powder by gas atomization method. For this purpose, AM60 magnesium alloy powder production was studied in order to fill this gap in literature. Theory and Methods: Experimental studies were carried out in the gas atomization unit in Karabuk University Technology Faculty Manufacturing Engineering Department. The experiments were carried out at a constant temperature of 820 ° C with a 2 mm nozzle diameter and 4 different gas pressures (5, 15, 25, 35 bar). Argon gas was used to atomize the melt. In order to determine the shape of the AM60 powder produced, scanning electron microscope (SEM), XRD, XRF and SEM-EDX analysis were used to determine the phases formed in the internal structures of the powders and the% ratios of these phases, and laser measuring device was used for the powder size analysis. Hardness tests were performed to determine the mechanical properties of the powders produced. Results: As a result of experimental studies, it was observed that the size of the powder decreased due to the increase of gas pressure. It has been found that gas pressure has a significant effect on powder size and shape in powder production by gas atomization method. Powder produced is generally observed in the form of ligament, droplet, acicular, flake and spherical shape. As a result of the XRD analysis, α (Mg main matrix) phase, β phase Mg17Al12 and very small amount of Mn were detected in the structure. The hardness of the powders produced is higher than the hardness of ingot material (67 HV0,025). Conclusion: In the gas atomization unit, the production of magnesium alloy AM60 powder was carried out by the gas atomization method, which is widely used in the production of powders. In the production of gas atomized magnesium alloy AM60 powder, the smallest powder size was measured as 820 °C, 2 mm nozzle diameter and 35 bar pressure as 41.95 µm. As a result of XRF analysis, it was determined that the AM60 powder produced and the chemical composition of the ingot material were close.