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The dynamic recrystallization (DRX) behavior of 47Zr-45Ti-5Al-3V alloy was studied by using the experiment and numerical simulation method based on DEFORM-3D software and cellular automata (CA) over a range of deformation temperatures (850 to 1050 °C) and strain rates (10−3 to 100 s−1). The results reveal that the DRX behavior of 47Zr-45Ti-5Al-3V alloy strongly depends on hot-working parameters. With rising deformation temperature (T) and decreasing strain rate (ε˙), the grain size (dDRX) and volume fraction (XDRX) of DRX dramatically boost. The kinetics models of the dDRX and XDRX of DRX grains were established. According to the developed kinetics models for DRX of 47Zr-45Ti-5Al-3V alloy, the distributions of the dDRX and XDRX for DRX grains were predicted by DEFORM-3D. DRX microstructure evolution is simulated by CA. The correlation of the kinetics model is verified by comparing the dDRX and XDRX between the experimental and finite element simulation (FEM) results. The nucleation and growth of dynamic recrystallization grains in 47Zr-45Ti-5Al-3V alloy during hot-working can be simulated accurately by CA simulation, comparing with FEM.

The effect of hot working parameters on the microstructure and texture evolution of the hot-deformed Zr-45Ti-5Al-3V alloy was studied by the electron backscatter diffraction (EBSD) technique. It was found that a high density of dislocations were generated when the alloy was deformed at 700 °C/0.001 s−1 and 800 °C/1 s−1. With the increment in hot-deformation temperature and the decrease in strain rate, the dislocation density decreased due to the increase in dynamic recrystallization (DRX) degree. The discontinuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) mechanisms co-existed during the hot working of the Zr-45Ti-5Al-3V alloy at a true strain of 0.7. The texture evolution of the alloy during hot working was characterized and the texture component mainly consisted of {001}<100>, {011}<100>, {110}<112>, and {112}<110> textures. The volume fractions of {001}<100> and {011}<100> textures obviously rose with the reduction in strain rate, whereas those of {110}<112> and {112}<110> textures gradually decreased. At a given strain rate, an increase trend in the volume fraction of the {001}<100> texture was observed with rising hot-deformation temperature, while the volume fraction of the {011}<100> texture first increased and then decreased. An opposite trend was visible in the {112}<110> and {110}<112> texture compared with {011}<100> textures.

In this work, (1-x)K0.5Na0.5NbO3–xBiMg0.5Sn0.5O3 [(1-x)KNN–xBMS] ceramics were prepared by the conventional solid-reaction method and the microstructure and electrical properties were investigated. The results suggest that the BMS accounts for the R-C relaxor phase transition due to an out-plane deformation as well as nearly unchanged c. Such phase transition is demonstrated by the temperature-dependent dielectric constants and accordingly calculated dispersion degree. The oxygen vacancy migration is dominating polarization in the ceramics, which is confirmed by complex impedance. Also, such migration gives birth to the hysteretic dielectric response with the increase of x. However, the energy storage performance is enhanced compared to KNN, indicating that the addition of Mg and Sn according to their energy band structures is an efficient way to induce the relaxor phase transition and associated good energy storage performance.