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This paper prepared Cu-ZrO2 composite by a modified internal oxidation in order to improve the high temperature strength of resistance Spot-welding electrode. The results showed that with the increasing of the cold deformation, Hardness increased while electrical conductivity decreases. Hardness reached 100HV and electrical conductivity was up to 86%IACS after cold drawn in 56%. With the increasing of annealing temperature and annealing time, Hardness of the composite decreased more slowly compared with the conventional Cu-Cr-Zr alloy and was higher than that of the Cu-Cr-Zr alloy after annealed above 700°C for 2h and at 600°C for 5h , which was attributed to the dispersion strengthening effect of the Zirconia particles. Thus, the Cu-ZrO2 composite has good high-temperature stability and can be used for the electrode

Nanocrystalline TiO2 powders were obtained at a low temperature between 50 and 80 oC by a hydrolysis of TiCl4 in a mixed solution of distilled water and alcohol. The as-synthesized TiO2 powders were characterized by X-ray diffraction analysis, transmission electron microscopy, and UVvisible absorption spectroscopy. Effects of the reaction temperature and the NH4F concentration on the formation of the nanocrystalline TiO2 powders were investigated. Results indicate that the reaction temperature greatly affects the particle size of the as-synthesized samples, and the NH4F concentration has a great effect on the phase structure of the as-synthesized samples. In addition, the photocatalytic activities of the as-synthesized samples for rhodamine B were also measured, and it is found that the sample synthesized from the NH4F concentration of 30 mM exhibits a higher photocatalytic activity than the P25 powder due to a high surface area and a pure anatase phase.

Hollow BiVO4 microspheres composed of nanosized particles were successfully prepared via a simple hydrothermal reaction route at 170C for 12 h. The crystal structures, morphologies, and optical properties of the as-prepared samples were characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and UV-visible absorption spectra (UV-vis). Simulated Sun-light induced photocatalytic degradation of Rhodamine B by hollow BiVO4 microspheres has been investigated, and the results show the hollow structures with excellent photocatalytic activity.

In-situ production of (Fe,Cr)7C3 particulate bundles-reinforced iron matrix composites were prepared by infiltration casting between Cr wires and white cast iron at 1200℃ plus subsequent heat treatment. The composites prepared under different heat treatment time were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), macrohardness test and pin-on-disc wear resistance test. The results show that the composite is mainly consist of (Fe,Cr)7C3 carbides and γ-Fe. The area of the particulate bundles gradually increases with the increase of heat treatment time, the microstructure evolved from eutectic to hypoeutectic, and the morphologies of the reinforcements present chrysanthemum-shaped, granular and intercrystalline eutectics, respectively. The (Fe,Cr)7C3 particulate bundles reinforced composite has high macrohardness and excellent wear resistance under dry sliding wear testing conditons.

In-situ production of (Fe,Cr)7C3 particulate bundles -reinforced iron matrix composite was prepared by infiltration casting between Cr wires and white cast iron at 1200℃ plus subsequent heat treatment. The composites under different heat treatment times were comparatively characterized by scanning electron microscopy (SEM) and pin-on-disc wear resistance tests. The results show that the area of the particle bundles gradually increases with the heat treatment time increasing, and the chemical compositions change from eutectic to hypoeutectic, the morphologies of the reinforcements present chrysanthemum-shaped, granular and intercrystalline eutectics. Under 5 N loads, the composites appear excellent wear resistance, which is 36 times for the reference sample.

Nano- and micro-scaled LiFePO4 was synthesized by hydrothermal synthesis method using disodium ethylenediamine tetraacetate (Na2EDTA)-assisted to avoid the Fe(II) ions from oxidation and control the growth of the crystal. The as-synthesized samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), The SEM showed that the pH value of the synthesis solution played a key role in the formation of the final products with different morphologies. Charge–discharge cycling performances were used to characterize its electrochemical properties. The results indicated that the nano-sized LiFePO4 presents enhanced discharge capacities (148 mAhg−1 at 0.1C-rate) and stable cycling performance. This study offered a simple method to design and synthesis nano-sized cathode materials for lithium-ion batteries.

The method of infiltration casting plus heat treatment process employing chromium wires and cast iron applied to in-situ synthesized (Fe,Cr)7C3 particulates bundle reinforced iron matrix composites. The phase analysis, microstructure, microhardness and wear-resistance of composite were observed and measured. The results show that it is possible to fabricate (Fe,Cr)7C3 particulates bundle reinforced iron matrix composite produced by this technology, and a special structure which called particulates bundle was fabricated. (Fe,Cr)7C3 particulates bundle were distributed in the forms of granular, lath-shaped and hexagon-shaped in the particulates bundle. The macrohardness of particulates bundle was 52 HRC, and the relative wear resistance of the composites is 2.3—23 times higher than that of the cast iron.

Eu3+ -doped GdVO4 powders have been synthesized via a novel hydrothermal method using commercially available Gd2O3, NH4VO3 and Eu2O3 as the reacting precursors. The influences of several important parameters, such as hydrothermal temperature, reaction time and pH value, of the experiment were investigated. The obtained samples were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), and photo-luminescence spectroscopy (PL). The experimental results showed that the optimal reaction condition was processed at 180˚C for 12 h and adjusted pH value to 4. The morphology of products was uniform pseudo-octahedron with a little conglomeration. All the phosphors exhibit the characteristic dominant red emission of Eu3+ ion (5D0 → 7F2) at 618nm.

In the paper, tungsten carbide (WC) particles can be in-situ synthesized by applying electromagnetic field to the system consisting of tungsten wires and gray cast iron melt at 1573 K. The microstructures and wear-resistant properties of composites reinforced by both WC particles and the residual tungsten wires were investigated by XRD, SEM, EDS, micro-hardness and pin-on-disc wear measurements. The results show that, with enhancing frequencies of electromagnetic field from 0 to 5 KHz, the amounts of in-situ WC particles increased and of the residual tungsten wires gradually decreased until tungsten wires completely reacted. Due to the higher hardness of in-situ WCp(2100-2231HV0.1) and the strong interfacial bonding, the composites displayed an excellent wear-resistant properties. When the frequency was 5 kHz, the wear loss for the composite fabricated was optimal and 2.69 times lower than that of reference samples.