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This paper concerns the elastic properties of Dy2Fe14B crystal investigated by ab-initio calculations. We determined the elastic constants of the considered crystal: C11 = 297, C12 = 92, C13 = 99, C33 = 287, C44 = 82, C66 = 80 GPa. Moreover, estimated from elastic constants physical properties (acoustic wave velocities, elastic moduli, Debye and melting temperature) are consistent with the reference data obtained for other (RE)2Fe14B crystals. [ABSTRACT FROM AUTHOR]

The paper refers to determination of magnetic coupling between Dy2Fe14B hard and Fe soft magnetic phases by first-principle calculations. The supercell used in our simulations was composed of Dy2Fe14B unit cell and thin layer of body-centered Fe-bcc structure, separated by distance of 1–5 Å. It was shown that the magnetic order depends on the interface direction and the distance which is presented and discussed in the paper. [ABSTRACT FROM AUTHOR]

The present paper pertains to mechanical properties and structure of nanocrystalline multiferroic BeFiO3 (BFO) thin films, grown by atomic layer deposition (ALD) on the Si/SiO2/Pt substrate. The usage of sharp-tip-nanoindentation and multiple techniques of structure examination, namely, grazing incidence X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectrometry, enabled us to detect changes in elastic properties (95 GPa≤E≤118 GPa) and hardness (4.50 GPa≤H≤7.96 GPa) of BFO after stages of annealing and observe their relation to the material’s structural evolution. Our experiments point towards an increase in structural homogeneity of the samples annealed for a longer time. To our best knowledge, the present report constitutes the first disclosure of nanoindentation mechanical characteristics of ALD-fabricated BeFiO3, providing a new insight into the phenomena that accompany structure formation and development of nanocrystalline multiferroics. We believe that our systematic characterization of the BFO layers carried out at consecutive stages of their deposition provides pertinent information which is needed to control and optimize its ALD fabrication. [ABSTRACT FROM AUTHOR]

The presented work was focused on investigating the influence of the (hafnium and zirconium)/molybdenum ratio on the microstructure and properties of Ti20Ta20Nb20(ZrHf)20−xMox (where: x = 0, 5, 10, 15, 20 at.%) high entropy alloys in an as-cast state. The designed chemical composition was chosen due to possible future biomedical applications. Materials were obtained from elemental powders by vacuum arc melting technique. Phase analysis revealed the presence of dual body-centered cubic phases. X-ray diffraction showed the decrease of lattice parameters of both phases with increasing molybdenum concentration up to 10% of molybdenum and further increase of lattice parameters. The presence of two-phase matrix microstructure and hafnium and zirconium precipitates was proved by scanning and transmission electron microscopy observation. Mechanical property measurements revealed decreased micro- and nanohardness and reduced Young's modulus up to 10% of Mo content, and further increased up to 20% of molybdenum addition. Additionally, corrosion resistance measurements in Ringers' solution confirmed the high biomedical ability of studied alloys due to the presence of stable oxide layers. [ABSTRACT FROM AUTHOR]

The presented work was focused on investigating the influence of the (hafnium and zirconium)/molybdenum ratio on the microstructure and properties of Ti 20 Ta 20 Nb 20 (ZrHf) 20 -x Mo x (where: x = 0, 5, 10, 15, 20 at.%) high entropy alloys in an as-cast state. The designed chemical composition was chosen due to possible future biomedical applications. Materials were obtained from elemental powders by vacuum arc melting technique. Phase analysis revealed the presence of dual body-centered cubic phases. X-ray diffraction showed the decrease of lattice parameters of both phases with increasing molybdenum concentration up to 10% of molybdenum and further increase of lattice parameters. The presence of two-phase matrix microstructure and hafnium and zirconium precipitates was proved by scanning and transmission electron microscopy observation. Mechanical property measurements revealed decreased micro- and nanohardness and reduced Young's modulus up to 10% of Mo content, and further increased up to 20% of molybdenum addition. Additionally, corrosion resistance measurements in Ringers' solution confirmed the high biomedical ability of studied alloys due to the presence of stable oxide layers.