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Investigations into crystal structure, electronic and elastic properties of M 3 AlN (M=Hf, Zr) had been conducted by plane-wave pseudopotential calculations. The absence of band gap at the Fermi level and the finite value of the density of states at the Fermi energy reveal the metallic behavior of these two compounds. The charge density distributions and density of states indicate that there exist relatively soft Al–M and strong N–M covalent bonds, which might be contributed to layered chemical bonding character of M 3 AlN. By analyzing Cauchy pressure and the bulk modulus to C 44 ratio, Hf 3 AlN was predicted to be more ductile than Zr 3 AlN.

A series of (Fe 50 Ni 50 ) x Cu 1− x granular films were prepared using the magnetron-controlled sputtering method. The nanoparticle morphology and giant magnetoresistance (GMR) of FeNi–Cu films deposited at room temperature were investigated through the transmission electron microscope (TEM) and the conventional four probes method under room temperature, respectively. Upon varying the magnetic volume fraction x , the GMR of as-deposited FeNi–Cu films reached a maximum of about 1.8% at a volume fraction of 32% FeNi. In addition, TEM observation disclosed that FeNi–Cu films consist of FeNi nanoparticles dispersed in Cu matrix and form FCC structure. For films with lower volume fraction of FeNi particles, the size distribution of FeNi particles satisfied a log-normal function. With increasing volume fraction of FeNi particles, the size distribution of FeNi particles deviated gradually from a log-normal function. Meanwhile, the average size of FeNi particles increased monotonically with increasing volume fraction of FeNi particles, leading to the fact that GMR can reach a peak value at a certain middle particle size. In addition, the relationship between GMR and nanoparticle morphology of granular films was discussed.

Investigations into the structural, electronic and elastic properties of intermetallic CuZr compound had been conducted by the plane-wave pseudopotential method. The calculated lattice constant was consistent well with the experimental value. The absence of band gap and finite value of the density of states (DOS) at the Fermi level reveal the metallic behavior of CuZr crystal, and Zr 4d states give rise to the electrical conductivity. The calculated elastic constants for single crystal CuZr at zero pressure obey the cubic mechanical stability condition, which indicates that the cubic CuZr crystal is mechanical stable at zero pressure. By analyzing the ratio between the bulk and shear moduli, we conclude that CuZr crystal is ductile in nature. The present theoretical investigations might give prediction to polycrystalline CuZr system.