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In this work, the mechanical characteristics of high-entropy alloy Co20Cr26Fe20Mn20Ni14 with low-stacking fault energy processed by cryogenic and room temperature high-pressure torsion (HPT) were studied. X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses were performed to identify the phase and microstructure variation and the mechanical properties characterized by Vickers hardness measurements and tensile testing. Cryogenic HPT was found to result in a lower mechanical strength of alloy Co20Cr26Fe20Mn20Ni14 than room temperature HPT. Microstructure analysis by SEM and TEM was conducted to shed light on the microstructural changes in the alloy Co20Cr26Fe20Mn20Ni14 caused by HPT processing. Electron microscopy data provided evidence of a deformation-induced phase transformation in the alloy processed by cryogenic HPT. Unusual softening phenomena induced by cryogenic HPT were characterized by analyzing the dislocation density as determined from X-Ray diffraction peak broadening.

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The research demonstrates microstructural changes and development of specific texture in Ti-6Al-4V specimens produced by electron beam melting (EBM) under different conditions. The effect of two factors, namely, raw material (powder) recycling and hot isostatic pressing (HIP), on the EBM produced samples structure and properties, has been explored. The as-printed and treated samples were investigated using electron backscattered diffraction (EBSD) analysis. Modification of mechanical properties after the EBM and HIP are explained by the EBSD data on microstructural phenomena and phase transformations. The work is devoted to assessing the possibility of reusing the residual titanium alloy powder for the manufacture of titanium components by the combination of EBM and HIP methods.

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We report the observation of ferroelectricity in hafnium-zirconium-oxide thin films in the as-deposited state, namely, after deposition at a low temperature of 300 °C without post-metallization annealing. The Hf0.5Zr0.5O2 (HZO) thin film was interposed between two TiO2 interlayers, and all films were produced by plasma enhanced atomic layer deposition and integrated into a TiN-based metal-insulator-metal capacitor. The ferroelectric nature of the as-deposited HZO film was evaluated by a polarization-voltage hysteresis loop, and a 2Pr value of ∼7.4 μC/cm2 was achieved. Grazing incidence x-ray diffraction measurements and atomic-resolution scanning transmission electron microscopy characterization revealed the co-existence of fully crystallized polar orthorhombic and monoclinic phases of the dielectric in the as-deposited sample. We concluded that the nucleation and growth of the crystalline polar non-centrosymmetric orthorhombic phases in the 10 nm HZO thin film were prompted by the available energy from the plasma and the tensile lattice mismatch strain provided by the TiO2 interlayer.

Cadmium chalcogenides–metal hybrid nanostructures play an important role in a wide range of applications and are key components in photocatalysis. Hence, great efforts have been devoted to the exploration of a variety of metal components, each offering different functionalities. Silver is a vital catalyst used in the production of major industrial chemicals, found in virtually every electronic device, widely exploited as an antibacterial agent, used in fuel cells, and has been extensively investigated for CO2 reduction. Yet, silver nanoparticles were not utilized in conjunction with cadmium chalcogenide colloidal nanostructures due to the tendency of Ag+ to undergo cation exchange. We present here a new strategy that opens up a pathway for avoiding cation exchange and obtaining metallic silver tipping on cadmium chalcogenide nanorods. The formation of Ag trioctylphosphine complex, as an intermediate in the course of Ag deposition on nanorods, was identified to be a critical step, which prevents undesirable cation exchange. Metallic Ag was confirmed by several advanced techniques and its growth location on the tip of nanorods was carefully studied. Moderate control over the crystalline Ag tip size was demonstrated in the range of 1.5–5.4 nm.

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