Copper oxide thin films were obtained using pulsating spray pyrolysis method. The morphological, structural, and optical properties of fabricated films were studied. X-ray analysis revealed that the CuO thin films are single-phase. The study of films morphology by SEM and AFM methods showed that the obtained films have a fairly high surface roughness and contain grains of different shapes and sizes. It was found that the obtained films of copper oxide have high values of the absorption coefficient, which confirms the possibility of their use as absorbing layers for solar cells. The obtained values of the optical band gap of the material are in the range from 1.45 eV to 1.60 eV. Raman spectroscopy revealed three modes A_1g, B_1g, and B_2g, of the crystal structure of monoclinic CuO. The devices based on p-type copper oxide are promising for solar cells fabrication because they can reduce production costs, due to their low cost and inexpensive production methods compared to silicon solar cells fabrication.

Poisson’s ratio is one of the fundamental characteristics in the material models that are used. In engineering practice, its values are assumed to be constant in the elastic and in the plastic region. In this paper, the conventionally used values of this number for steel materials and aluminum alloys are confronted with experimental results. By using non-contact strain measurements with the DIC (digital image correlation) method, the evolution of the Poisson ratio value in the regions of transition from the elastic to the plastic region as well as in the regions of large plastic deformations was documented. The obtained experimental results are graphically compared using the proposed strain scaling. The gradient of the Poisson ratio changes in the vicinity of the yield stress is significant, indicating the need for a refinement of the material models in this region. Deviations from the conventionally used value of this number were found in the large plastic deformation region. In conclusion, a possible approach for improving the accuracy of simulations in FEM softwares was formulated.

Additive metals are practically identical in strength to the properties of conventionally produced materials. This article experimentally analyses strength properties and fatigue properties in the tensile–pressure mode for two different directions of 3D printing of AlSi₁₀Mg material. The resulting fatigue parameters of the Basquin curve are confronted with a conventionally produced alloy of the same composition. The microstructure analysis explains the different fatigue properties obtained by these two material production technologies. Phenomena such as strength enhancement in additive manufacturing material, anisotropy of cyclic properties, and cyclic hardening are discussed. The limits of current additive manufacturing are clarified, and the future direction of research in this field is outlined.

Trapping effects on two AlGaN/GaN Schottky diodes with a different composition of the AlGaN barrier layer were analyzed by current transient spectroscopy. The current transients were measured at a constant bias and at six different temperatures between 25 and 150 °C. Obtained data were fitted by only three superimposed exponentials, and good agreement between the experimental and fitted data was achieved. The activation energy of dominant traps in the investigated structures was found to be within 0.77–0.83 eV. This nearly identical activation energy was obtained from current transients measured at a reverse bias of −6 V as well as at a forward bias of+1 V. It indicates that the dominant traps might be attributed to defects mainly associated with dislocations connected predominantly with the GaN buffer near the AlGaN/GaN interface.