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Knowledge about the thermodynamic equilibria of the P2O5-Na2O and P2O5-MgO systems is very important for controlling the phosphorus content of steel materials in the process of steelmaking dephosphorization. The phase equilibrium and thermodynamic data of the P2O5-Na2O and P2O5-MgO systems were critically evaluated and re-assessed by the CALPHAD (CAlculation of PHAse Diagram) approach. The liquid phase was described by the ionic two-sublattice model for the first time with the formulas (Na+1)P(O−2, PO3−1, PO4−3, PO5/2)Q and (Mg+2)P(O−2, PO3−1, PO4−3, PO5/2)Q, respectively, and the selection of the species constituting the liquid phase was based on the structure of the phosphate melts. A new and improved self-consistent set of thermodynamic parameters for the P2O5-Na2O and P2O5-MgO systems was finally obtained, and the calculated phase diagram and thermodynamic properties exhibited excellent agreement with the experimental data. The difference in the phase composition of invariant reactions from the experimentally determined values reported in the literature is less than 0.9 mol.%. The present thermodynamic modeling contributes to constructing a multicomponent oxide thermodynamic database in the process of steelmaking dephosphorization. [ABSTRACT FROM AUTHOR]

Light‐fueled self‐oscillators based on stimuli‐responsive soft materials have been explored toward the realization of a myriad of nonequilibrium robotic functions, such as adaptation, autonomous locomotion, and energy conversion. However, the high energy density and unidirectionality of the light field, together with the unscalable design of the existing demonstrations, hinder their further implementation. Herein, a light‐responsive lampshade‐like smart material assembly as a new self‐oscillator model that is unfettered by the abovementioned challenges, is introduced. Liquid crystal elastomer with low phase transition temperature is used as the photomechanical component to provide twisting movement under low‐intensity incoherent light field. A spiral lampshade frame ensures an equal amount of light being shadowed as negative feedback to sustain the oscillation upon constant light field from omnidirectional excitation (0°–360° azimuth and 20°–90° zenith). Different‐sized oscillators with 6, 15, and 50 mm in diameter are fabricated to prove the possibility of scaling up and down the concept. The results provide a viewpoint on the fast‐growing topic of self‐oscillation in soft matter and new implications for self‐sustained soft robots. [ABSTRACT FROM AUTHOR]

The investigation of the Al–Ag–Zr system is crucial for the development of heat-resistant Al alloys, which are essential for applications in high-temperature environments. In this work, we first determined the isothermal sections of the Al–Ag–Zr system at 500 and 600 °C using equilibrium alloys. Simultaneously, the τ3 (Al6AgZr6) phase was identified by transmission electron microscopy (TEM). In addition, the three-phase equilibrium of τ3 + AgZr + (Ag) instead of Al3Zr4 + AgZr + (Ag) was confirmed at 500 and 600 °C. The formation enthalpies of the end-members and ternary compounds in the Al–Ag–Zr system were calculated via first-principles calculations. Based on the experimental and computational results, a thermodynamic database of the Al–Ag–Zr system was established using the CALPHAD (calculation of phase diagrams) method. The hardness of τ1 (Al2.68Ag0.32Zr) and τ2 (Al1.84Ag0.16Zr) were determined to be 3.82 and 10.20 GPa, respectively, using nanoindentation. The introduction of the τ2 phase in the design of Al alloys can considerably increase the mechanical properties of the alloys. [ABSTRACT FROM AUTHOR]