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Cu-12% Fe (in weight) composite was prepared by casting, pretreating, and cold drawing. The microstructure was observed and Vickers hardness was measured for the composite at various drawing strains. Cu and Fe grains could evolve into aligned filaments during the drawing process. X-ray diffraction (XRD) was used to analyze the orientation evolution during the drawing process. The axial direction of the filamentary structure has different preferred orientations from the radial directions. The strain of Fe grains linearly increases with an increase in the drawing strain up to 6.0, and deviates from the linear relation when the drawing strain is higher than 6.0. With an increase in the drawing strain, the microstructure scales of Fe filaments exponentially decrease. The density of the interface between Cu and Fe phases exponentially increases with an increase in the aspect ratio of Fe filaments. There is a similar Hall-Petch relationship between the hardness and Fe filament spacing. The refined microstructure from drawing deformation at drawing strains lower than 3.0 can induce a more significant hardening effect than that at drawing strains higher than 3.0.

CaNdFeO 4 ceramics were prepared using a solidstate process, and their crystal structure was identified by Rietveld method, while the electrical conductivity was evaluated as a function of sintering and testing temperatures. CaNdFeO 4 ceramics had an orthorhombic K 2 NiF 4 structure, and a secondary perovskite phase (Ca,Nd)FeO 3AEd was observed in the samples. The DC electrical conductivity of CaNdFeO 4 ceramics increased firstly to a maximum value, 0.065 Scm −1 , and then decreased with increasing sintering temperature. The relationship between electrical conductivity of CaNdFeO 4 ceramics and testing temperature obeyed the Arrhenius law.

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