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The electronic and magnetic properties of Ag, Cu or Mg doped NiO are systematically studied in order to reveal the ferromagnetic half-metallic behavior by means of first-principle calculations. In the band structure and density of states (DOS), we find that impurity states crossing Fermi level are induced in the spin down channel, while band gap only appears in the Ni31XO32 (X = Ag, Cu) systems in the spin up channel. The analysis of electron spin density and magnetic show that the dopant atoms (Ag or Cu) and its neighbor O atoms exhibit strong polarization as well as the resultant magnetic moments. However, Mg doping system do not exhibit similar phenomenon. These results indicate that the nonmagnetic dopants of Ag or Cu can introduce the ferromagnetic half-metallic properties in the Ni31AgO32 or Ni31CuO32 system.

Based on the Stillinger–Weber potential, molecular dynamics simulations of the solidification processes of multicrystalline silicon were carried out. Every stage of the whole solidification process, including homogeneous nucleation, grain growth, grain coarsening and defect characterization, was investigated. In the nucleation stage, it showed two typical nucleation models (spontaneous nucleation and sporadic nucleation) at high and low temperatures. Local heterogeneity was occasionally observed during homogeneous nucleation. The simulated nucleation rates at different temperatures were measured, whose trends were in agreement with the results of theoretical calculations, and both of them reached the maximum nucleation rate at a critical temperature of ∼0.65Tm. In the growth stage, the nuclei showed the maximum growth exponent at ∼0.65Tm. The evolution of the grain number at different temperatures exhibited three different patterns. Furthermore, the grains showed modest anisotropic growth before the growth was influenced by other grains. In the grain coarsening stage, the grain size distribution could be described suitably by the log-normal distribution. The grain coarsening exponent was approximately one order of magnitude lower than the nuclei growth exponent. The analyses of crystal defects showed that the dislocation density is about 105 m−2, twin percentages are above 40%, and the percentage of CSL grain boundaries is about 30.30% in mc-Si of the simulations. The statistics of crystal defects are similar to experimental results.

As-cast Cu-1.5Fe-0.5Co (wt%) alloy displays both high tensile strength of 307 MPa and elongation of 33%. In situ transmission electron microscopy was used to investigate crack propagation in the alloy, to analyze the origin of the good properties. At different deformation stages in thin Cu foils, the interactions of a propagating crack with iron-rich nanoparticles and growth twins are investigated. Crack-bridging processes via near-tip twinned bridges were identified. The multiple deformation mechanisms act synergistically to contribute to high strength and high ductility in the alloy.

Magnesium-based bulk metallic glass matrix composites (BMGMCs) have better plasticity than the corresponding bulk metallic glasses (BMGs); however, their strength and density are often compromised due to the fact that the effective reinforcement phase is mostly plastic heavy metal. For lightweight SiC-particle reinforced BMGMCs, interface wettability and the sharpness of the particles often reduce the strengthening effect. In this work, SiC particles were coated with a thin Cu coating by electroless plating, and added to Mg54Cu26.5Ag8.5Gd11 melt in an amount of 5 wt % to prepare a BMGMC. The microstructure of the interface, mechanical behavior and fracture morphology of the BMGMC were studied by scanning electron microscopy and quasi-static compression testing. The results showed that the Cu coating improved the wettability between SiC and the matrix alloy without obvious interfacial reactions, leading to the dispersion of SiC particles in the matrix. The addition of Cu-coated SiC particles improved the plastic deformation ability of Mg54Cu26.5Ag8.5Gd11 BMG, proving that electroless plating was an effective method for controlling the interface microstructure and mechanical behavior of BMGMCs.