Two novel La3+ and Ti4+ cosubstituted Sr3LaNb3O12 ceramics, Sr2La2TiNb2O12 and SrLa3Ti2NbO12, were prepared and the effect of substitution on the microwave dielectric properties was investigated. Results showed that as the amounts of substitution increased, dielectric constant (εr) increased from 36 to 41, and temperature coefficient of resonant frequency (τf) improved from −9 to 3 ppm/°C, whereas the quality factor (Q×f) decreased from 45,000 to 33,600 GHz. A temperature-stable microwave dielectric ceramics SrLa3Ti2NbO12 with τf of 3 ppm/°C, εr of 41, Q×f of 33,600 GHz was obtained; it might be a promising candidate for practical application in base stations if the quality factor is enhanced beyond 40,000 GHz.

Al85Gd8Ni5Co2 metallic glass was subjected to partial devitrification by high-pressure torsion, continuous heat treatment, and isothermal annealing. The fully amorphous alloy exhibits a well-defined transition in its first devitrification product during isothermal heat treatments from τm + α-Al phase mixture to primary α-Al by increasing the annealing temperature above 555 K. This thermal sensitivity predestinates the composition to identify the controversial thermal contribution of the plastic deformation in metallic glasses. Thermal stability and structure of the partially devitrified samples were systematically analyzed and compared by calorimetry, x-ray diffraction, and electron microscopy. It seems that the effect of severe deformation cannot be singled out by a simple isothermal heat treatment; i.e., high-pressure torsion acts as a spectrum of heat treatments performed at different annealing temperatures.

Y2Ba4CuNbO12 (Y-24Nb1) and silver (Ag) are recognized as potential candidates for improving both flux pinning and the mechanical properties of bulk rare earth (RE)–Ba–Cu–O [(RE)BCO] high-temperature superconductors (HTS). Recent attempts to add Ag2O to superconducting Y-123/Y2Ba4CuNbO12 composites, however, have produced a highly anisotropic morphology of Ag particles in samples grown by top-seeded melt growth (TSMG). This morphology has been attributed to strong particle pushing effects due to the presence of Y-24Nb1 nanoparticles in the composite microstructure. An investigation of the formation of anisotropic Ag particles in the YBCO bulk microstructure indicates that these pushing effects generate different morphological microstructural zones in the composite. These include a zone free of inclusions other than acicular Ag particles, a zone of segregated additives (i.e., Y-24Nb1, Y-211, and Ag), and a zone containing fine Ag and other particles distributed uniformly throughout the local microstructure. The particle pushing/trapping theory has been used to explain these extraordinary features of the distribution of Ag inclusions. The superconducting and mechanical properties of samples containing very fine silver inclusions are also discussed briefly.

A new elpasolite-type (NH4,K)3VO2F4 compound was prepared and characterized by x-ray diffraction, differential scanning calorimeter (DSC), impedance analysis, and electrical polarization measurements. It crystallizes in an orthorhombic lattice with unit-cell parameters: a = 8.9584(4), b = 18.6910(14), c = 6.2174(4) Å, V = 1041.04(11) Å3, Z = 6. NH4+, and K+ ions are distributed statistically over crystallographically four equivalent sites. There are two distinguishable vanadium atoms forming cis- and trans-VO2F4 octahedra present in the unit cell. High-temperature studies by DSC and in situ x-ray diffraction revealed a first-order structural transformation from orthorhombic to cubic lattice around 343 K. Impedance measurements show two different kinds of conductivity behaviors for the two phases. In orthorhombic phase a significant conductivity resulting from involvement of protonic species is observed. In the orthorhombic phase, a clear ferroelectric hysteresis loop is observed.

Carbon nanofiber-supported Pt–Pd alloy composites were prepared by co-electrodepositing Pt–Pd alloy nanoparticles directly onto electrospun carbon nanofibers. The morphology and size of Pt–Pd alloy nanoparticles were controlled by the surface treatment of carbon nanofibers and the electrodeposition duration time. Scanning electron microscopy/energy dispersive spectrometer (SEM)/(EDS) and x-ray photoelectron spectroscopy (XPS) were used to study the composition of Pt–Pd alloy on the composites, and the co-electrodeposition mechanism of Pt–Pd alloy was investigated. The resultant Pt–Pd/carbon nanofiber composites were characterized by running cyclic voltammograms in oxygen-saturated 0.1 M HClO4 at 25 °C to study their electrocatalytic ability to reduce oxygen. Results show that Pt–Pd/carbon nanofiber composites possess good performance in the electrocatalytic reduction of oxygen. Among all Pt–Pd/carbon nanofibers prepared, the nanofiber composite with a Pt–Pd loading of 0.90 mg/cm2 has the highest electrocatalytic activity by catalyst mass.

Electroplastic manufacturing processing (EPMP) is a relatively new metal-forming process that is energy efficient, environmentally friendly, and versatile. In particular, it can be used to manufacture metals or alloys that are difficult to process by conventional manufacturing protocols. There have been significant advances in EPMP in the past decade, and this review summarizes our current state of understanding and describes recent developments in EPMP. Particular emphasis is placed on describing the mechanisms responsible for the electroplastic effect and microstructure evolution as well as major advances in EPMP of metals. Challenges facing theoretical and experimental investigations are also discussed.