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Abstract: Cu/Cu2O cermets were prepared with Cu2O matrix imbedded with branch-like or spherical Cu powders. The coefficients of thermal expansion (CTE) of them were tested. The CTE curves can be divided into three segments. From 25°C to 150°C, CTEs were found to decrease with temperatures. The CTEs were influenced by the structure of the conductor phase. For cermets prepared with spherical Cu, the increase in CTEs was basically linear with temperatures above 150°C. In contrast, cermets with same Cu content prepared with branch-like Cu had a CTE with an increasing rate as the temperature rose from 150°C to 900°C, and the increasing rates in these temperature range are much higher than those prepared with spherical Cu. [Copyright &y& Elsevier]

Abstract: Eu3+-doped CdMoO4 red phosphor was prepared by a simple aqueous solution process at room temperature. X-ray diffraction (XRD), scanning electron microscopy and transmission electron microscopy were used to characterize the phosphor. Emission and excitation spectra show that the phosphor exhibits a dominant red emission at 617nm with excitation wavelength of 300nm at room temperature. The red emission is visible to naked eye, indicating that CdMoO4 is a new promising host material for the rare-earth elements. This result may bring opportunity for the generation of rare-earth element doped complex metal oxides with low cost and gram scale production. [Copyright &y& Elsevier]

Abstract: The effects of age-forming on microstructures and mechanical properties of 7050 Al alloy were investigated in this work. The alloy was subjected to age-forming as well as stress-free ageing at 160°C for 6, 12, 18 and 24h, and its microstructures were characterized by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). It was shown that creep might lead to grain elongation during age-forming, and the applied stress induces the coarsening of precipitates in 7050 Al alloy. The texture in the alloy was also influenced by age-forming. Consequently, the differences in microstructures result in differences in mechanical properties of age-forming versus traditional stress-free ageing. The ultimate tensile strength of age-formed samples were slightly lower than that of stress-free aged samples, while the yield strength of age-formed samples were apparently lower than that of stress-free aged samples. Specifically, the elongation of samples age-formed displays apparently decrease. [Copyright &y& Elsevier]

Abstract: Adiabatic shear bands in Mg alloy under ballistic impact at a velocity of 0.5km·s−1 were characterized by means of optical microscope, scanning electron microscope, transmission electron microscope and indenter technique. The results show that adiabatic shear bands were formed around the impacted crater, and the deformed and transformed bands were distinguished by etching colors in metallographic observation. TEM observation shows that the deformed bands were composed of the elongated grains and high density dislocations, while the transformed bands composed of the ultrafine and equiaxed grains were confirmed. In initial stage, the severe localized plastic deformation led to the formation of elongated grains in the deformed bands. With localized strain increasing, the severe localized deformation assisted with the plastic temperature rising led to the severe deformation grains evolved into the ultrafine and equiaxed grains, while the deformed bands were developed into transformed bands. The formation of the ultrafine and equiaxed grains in the transformed bands should be attributed to the twinning-induced rotational dynamic recrystallization mechanism. High microhardness in the bands was obtained because of the strain hardening, grain refining and content concentration. [Copyright &y& Elsevier]

Abstract: Fe/SiO2 composite particles were synthesized by hydrogen reduction of Fe2O3/SiO2 precursor, which was prepared by sol–gel method. A reduction temperature higher than 600°C is required for the complete conversion of Fe2O3 to Fe. Fe/SiO2 composite particles exhibit superior complex permittivity and permeability in the microwave band. A reflection loss higher than −70dB as well as a broad absorption band can be simultaneously obtained for Fe/SiO2-based coatings about 2mm in thickness, suggesting that the Fe/SiO2 composite particles are a promising candidate for high performance electromagnetic absorption materials. [Copyright &y& Elsevier]

Abstract: CoFe alloy nanoparticles with different particle sizes were successfully prepared by hydrogen-thermal reduction of CoFe2O4 microspheres at different temperatures. It was found that the real part of the permeability of the CoFe alloy nanoparticles increased with the decrease of the particle size, and accordingly the reflection loss (RL) peak moved towards the low-frequency region. The maximum RL of the coating based on CoFe alloy nanoparticles exceeded −23dB, and a wide effective absorption band width (RL≤−10dB) of about 6GHz was simultaneously achieved. The EMA performance was confirmed to be tunable by the control of the absorber''s particle size, and thus a new clue for the design of the EMA applications was supplied. [Copyright &y& Elsevier]