Using a direct oxidation method in a horizontal quartz tube, copper oxide nanowires are grown on a Cu substrate. In order to investigate the growth temperature effects on the structural, morphological, electrical, and photocatalytic properties of the copper oxide nanowires, X-ray diffraction, scanning electron microscopy, a KEITHLEY 2361 system, and a homemade photoreactor are used. The X-ray diffraction results show that both CuO and Cu2O phases are formed, and while increasing the growth temperature, the crystallinity is improved and the intensity of most of the diffraction peaks increases. The scanning electron microscopy images at different growth temperatures show that the number, density, and length of the copper oxide nanowires on pre-formed micro-scaled grains increase, when the growth temperature increases to 700°C and sharper nanowires with average diameters of 1–3 µm grow on the surface. Also I–V curves show that by raising the growth temperature, the conductivity of the samples increases. In addition, the photocatalytic activities are studied by photocatalytic degradation of Congo red dye, and based on these results, the sample grown at 700°C with the highest number and density of the nanowires showed the best photocatalytic performance and electrical conductivity. The results can be used to guide better understanding of the growth behavior of copper oxide nanowires and can be useful for the development of novel photocatalytic nanodevices.

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Nickel-based alloys are used for a broad range of applications in oil and gas (O&G) production and marine engineering because of their good corrosion resistance and mechanical properties. The future of laser AM in the O&G industries is highly promising due to the ability to deliver cheaper and better parts quickly. As it is in the initial stages, rigorous research needs to be done to enhance the fabrication speed and parametric optimization to improve the thermo-mechanical properties of the fabricated components by laser powder bed fusion AM. Simulation methods provide financially viable and the least resource-consuming approach for the qualification of produced parts, enabling metallurgical and mechanical characterization in a short time. In this research study, a three-dimensional finite element model is developed to predict the temperature, residual stress, and distortion in nickel-based super alloy parts fabricated by a multi-layer laser powder-bed fusion (LPBF) process, to analyze the thermal and residual stress distributions. For this purpose, a FEM model of LPBF was applied that includes a thermal model representing the scanning laser thermal input, a material model to define the temperature-dependent material property in the cyclic heating and cooling environment, and a physics-based method to describe the layer build-up process. For validation of the results, the experimental results were used, and the validation results were presented.