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It is well known that grain-refinement has a positive impact on the mechanical properties of WC-Co cemented carbide. The effect of VC inhibitor and microwave on density, microstructure and mechanical properties of the sintered WC–12wt%Co alloy was investigated in the present study. The ball milled WC-12wt%Co-xVC composites were compressed and fabricated by using microwave sintering method. The experimental results indicate that the microwave sintering cycle was significantly shorter to that of vacuum processing, and the density of bulk alloys increased with VC inhibitor contents and microwave sintering temperatures. Moreover, the microstructure observation of the sintered samples suggests that VC inhibitor had prominent inhibitory action on WC grains in microwave exposure, and the WC average grain size of alloy with 0.7wt%VC inhibitor was 0.43μm when the sintering temperature reached 1420°C. It is also evident that WC-12wt% alloys with an appropriate proportion of VC inhibitor exhibited higher hardness (92.1HRA) and better transverse rupture strength (2380MPa). And finally the mechanism of inhibitory effects on WC grains under microwave irradiation was discussed.

A smooth and flexible carbon film was prepared via liquid exfoliation method followed by liquid evaporation using the natural flake graphite as the starting material. The XRD and Raman results demonstrated that the obtained film is composed of chemically reduced graphene, graphene oxide and graphite. The thermal transport property of the as-obtained film was investigated by light flash measurements. It is found that the as-obtained graphene-containing composite film has a high in-plane thermal diffusivity (2157 m2/s), and the corresponding thermal conductivity (754 W/m K) is higher than the other metal and normal graphite materials, which is very promising for applications requiring 2D heat conduction.

Amorphous Ti63.7Nb21.3Zr4.5Ta1.5Fe9 powder has been designed and fabricated by mechanical alloying (MA) from a mixture of pure titanium and other elemental powders under a purified argon gas atmosphere in a stainless steel vial together with stainless steel balls. The amorphous alloy powders were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that a transform from a well-developed dislocation substructure to a mixed nanocrystalline plus amorphous structure occurs in Ti63.7Nb21.3Zr4.5Ta1.5Fe9 when milling time increases from 0 h to 15 h. Moreover, amorphous Ti63.7Nb21.3Zr4.5Ta1.5Fe9 powders were prepared after mechanical milling for 40 h. The results obtained are of the most significance for future work of densification of the milled powders.

Spray rolling is a novel metallic semi-solid near-net-shape forming technology. This paper describes the qualitative influence of the key process parameters on the nucleation temperature during gas horizontal atomization stage in the spray rolling of 7050 aluminum alloy. The Newtonian heat transfer formulation has been coupled with heterogeneous nucleation, as well as the special solidification process. Results show that the droplet diameter has remarkable influence on nucleation temperature during spray rolling of 7050 aluminum alloy compared with that of wetting angle. The nucleation temperature approximately is 878K.