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Altering the content of an alloying element in alloy materials will inevitably affect the content of other elements, while the effect is frequently disregarded, leading to subsequent negligence of the common influence on the physical properties of alloys. Therefore, the correlation between alloying elements and physical properties has not been adequately addressed in the existing studies. In response to this problem, the present study focuses on the Al10Ti15Nix1Crx2Cox3 alloys and investigates the competitive interplay among Ni, Cr, and Co elements in the formation of physical properties through a single-element (SE) analysis and a multi-element (ME) analysis based on the first principles calculations and the partial least squares (PLS) regression. The values of C11 and C44 generally increase with the incorporation of Ni or Cr content in light of SE analysis, which is contrary to the inclination of ME analysis in predicting the impact of Ni and Cr elements, and the Ni element demonstrates a pronounced negative competitive ability. The overall competitive relationship among the three alloying elements suggests that increasing the content of Ni and Cr does not contribute to enhancing the elastic constants of alloys, and the phenomenon is also observed in the analysis of elastic moduli. The reason is that the SE analysis fails to account for the aforementioned common influence of multiple alloying elements on the physical properties of alloys. Therefore, the integration of SE analysis and ME analysis is more advantageous in elucidating the hidden competitive mechanism among multiple alloying elements, and offering a more robust theoretical framework for the design of alloy materials. [ABSTRACT FROM AUTHOR]

The impact of variations in the content of single alloying element on the properties of alloy materials has been extensively discussed, but the influence of this change on the content of multiple alloying elements in the alloy materials has been disregarded, as the performances of alloy materials should be determined by the collective influence of multiple alloying elements. To address the aforementioned issue, the present study conducted a comprehensive investigation into the impact of variations in the content of alloying elements, namely Ni, Cr, and Co, on the structural and mechanical properties of L12-(Nix1Crx2Cox3)3Al precipitates using the high-throughput first-principles calculations and the partial least squares (PLS) regression, and the competitive mechanism among these three elements was elucidated. The findings demonstrate that the same alloying element may exhibit opposite effects in both single element analysis and comprehensive multi-element analysis, for example, the effect of Ni element on elastic constant C11, and the influence of Cr element on Vickers hardness and yield strength. The reason for this is that the impact of the content of other two alloying elements is ignored in the single element analysis. Meanwhile, the Co element demonstrates a significant competitive advantage in the comparative analysis of three alloying elements for different physical properties. Therefore, the methodology proposed in this study will facilitate the elucidation of competition mechanisms among different alloy elements and offer a more robust guidance for experimental preparation. [ABSTRACT FROM AUTHOR]

The CdIn2S4 semiconductor is considered a potential host for the implementation of intermediate band solar cells due to its ideal bandgap value and excellent photoelectric property. In this paper, the electronic structures of group IV elements (Si, Ge, Sn, and Pb)-doped CdIn2S4 have been investigated by using hybrid density functional calculations. In the case of Ge, Sn, and Pb doping, an isolated and partially occupied intermediated band with delocalized characteristics could be created in the bandgap of the host. The results of the projected density of states reveal that the intermediated band is derived from the hybridization between the S-3p and dopant-ns states. Thanks to the assistance of the impurity band, the optical absorption ability of the intermediate band semiconductor is greatly enhanced. Based on the detailed balance theory, the theoretical efficiencies of intermediate band solar cells made by Ge- and Pb-doped CdIn2S4 are estimated to be 45.0% and 49.2%, respectively, which are superior to the Shockley and Queisser limit (40.7%) of a single junction photovoltaic device. Moreover, the experimental synthesis of these impurity semiconductors is relatively feasible because substitutional doping at the octahedral position is energetically favorable. These findings would be helpful to the development of a high-efficiency intermediate band solar cell. [ABSTRACT FROM AUTHOR]

In this paper, the R-cut sapphire single crystal substrates were selected, and the CeO2 buffer layers were grown on the surfaces of substrates by RF magnetron sputtering method, then the high quality Tl-1223 superconducting films were grown by the rapid heating-up sintering technology. The effects of buffer layer growth and post annealing conditions of the precursor films on the crystallization and superconducting properties of the superconducting thin films were studied. AFM and XRD measurements show that the surface of sapphire substrates have a step structure with smooth platform and the crystal quality of sapphire substrates have been improved after annealing; the CeO2 buffer layers and the Tl-1223 superconducting films all have good c-axis growth orientation under appropriate parameters, and they exist a good ab-plane texture. SEM measurements show that the well grown Tl-1223 superconducting films have a layered structure and their surfaces are dense and smooth. The Tc of the prepared superconducting film is measured to be about 111 K, and Jc (77 K, 0 T) is measured to be about 1. 3 MA/cm² in liquid nitrogen environment. [ABSTRACT FROM AUTHOR]

The complicated superdislocation dissociation, dislocation core properties, and slip mechanism of L12 structural alloys have been controversial. Herein, the generalized stacking‐fault energy surfaces (γ‐surfaces) of the {001}, {110}, and {111} planes in L12‐Al3RE (RE = Er, Tm, Yb, Lu) compounds are first calculated according to ab initio density functional theory. Based on the γ‐surfaces, the superdislocation dissociation modes are preliminarily estimated using the unstable and stable stacking‐fault energies and their ratio. The result shows that the possible type of dissociations cannot be determined just from these ratios. Then, the 2D Peierls–Nabarro (PN) model is applied to simulate the ⟨110⟩{111} superdislocation dissociation configuration evolution in L12‐Al3RE, and the complete dislocation properties, including the dissociation width, the dislocation movement, and the Peierls energy and stress, are also investigated. The present study indicates that the combination of the γ‐surface and the 2D PN model can comprehensively elucidate the superdislocation properties and deformation mechanisms of L12 structural alloys. [ABSTRACT FROM AUTHOR]

High‐throughput first‐principle calculations are implemented to study the structural, mechanical, and electronic properties of cubic XTiO3 (X = Ca, Sr, Ba, Pb) ceramics under high pressure. The effects of applied pressure on physical parameters, such as elastic constants, bulk modulus, Young's modulus, shear modulus, ductile‐brittle transition, elastic anisotropy, Poisson's ratio, and band gap, are investigated. Results indicate that high pressure improves the resistance to bulk, elastic, and shear deformation for XTiO3 ceramics. Pugh's ratios B/G reveal that CaTiO3 and PbTiO3 ceramics are ductile, but SrTiO3 and BaTiO3 ceramics are brittle under the ground state. The brittle‐to‐ductile transition pressures are 24.26 GPa for SrTiO3 and 43.23 GPa for BaTiO3. Under high pressure, the strong anisotropy promotes the cross‐slip process of screw dislocations, and then enhances the plasticity of XTiO3 ceramics. Meanwhile, XTiO3 (X = Ca, Sr, Ba) is intrinsically an indirect‐gap ceramic, but PbTiO3 is a direct‐gap ceramic. High pressure increases the band gap of XTiO3 (X = Ca, Sr, Ba) ceramic, but decreases that of PbTiO3 ceramic. This work is helpful for designing and applying XTiO3 ceramics under high pressure. [ABSTRACT FROM AUTHOR]

The CdIn2S4 semiconductor is considered a potential host for the implementation of intermediate band solar cells due to its ideal bandgap value and excellent photoelectric property. In this paper, the electronic structures of group IV elements (Si, Ge, Sn, and Pb)-doped CdIn2S4 have been investigated by using hybrid density functional calculations. In the case of Ge, Sn, and Pb doping, an isolated and partially occupied intermediated band with delocalized characteristics could be created in the bandgap of the host. The results of the projected density of states reveal that the intermediated band is derived from the hybridization between the S-3p and dopant-ns states. Thanks to the assistance of the impurity band, the optical absorption ability of the intermediate band semiconductor is greatly enhanced. Based on the detailed balance theory, the theoretical efficiencies of intermediate band solar cells made by Ge- and Pb-doped CdIn2S4 are estimated to be 45.0% and 49.2%, respectively, which are superior to the Shockley and Queisser limit (40.7%) of a single junction photovoltaic device. Moreover, the experimental synthesis of these impurity semiconductors is relatively feasible because substitutional doping at the octahedral position is energetically favorable. These findings would be helpful to the development of a high-efficiency intermediate band solar cell. [ABSTRACT FROM AUTHOR]