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Effect of 10% Ni on synthesis of Al2O3-TiB2 Composite ceramic powder during the mechanical alloy. X-ray diffraction phase analysis (XRD) and scanning electron microscope (SEM) were used to study the phase and morphology of particles which ball milling different time. The results show that: when adding 10%Ni, it generates Al2O3, TiB2 ceramic phase after 20h; In the process of mechanical alloying, the powder particles can agglomerate and then break up. It will accelerate the powder agglomeration for Ni is absorbed on the surface of Al particles, thus shorten the diffusion distance of the atom and accelerate the solid state reaction.

MoO3 was synthesized by thermal decomposition of ammonium molybdate. The structure and surface morphology of the as-prepared MoO3 was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The supercapacitive behaviour of MoO3 in 1 mol L-1 KCl electrolyte was studied by cyclic voltammetry (CV), galvanostatic charge-discharge cycling (CD). The affect of thermal decomposition temperature on the capacitive behaviour of MoO3 was also discussed here. The results indicate that MoO3 show good capacitive behaviour with a specific capacitance of 148.9 F g-1 at 0.7 A g-1. Thermal decomposition temperature has an important influence on the capacitive behaviour and crystallization of MoO3.

LaF3 and LaF3: Re (Re= Ce3+, Eu3+ and Tb3+) nanocrystals have been successfully synthesized by a facile and rapid microwave heating method. The structure, morphology and fluorescent properties of the as-prepared products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and photoluminescence spectroscopy (PL). XRD patterns showed that the undoped and doped LaF3 nanocrystals had hexagonal structure with good crystallinity and high purity. TEM and HRTEM images showed that the LaF3 nanocrystals have uniform sizes with mean diameter about 20 nm and are characteristic of inner cavities. The luminescence spectra of the LaF3: Re (Re= Ce3+, Eu3+ and Tb3+) nanocrystals indicated that different rare-earth ions have been successfully doped in LaF3 matrix via the microwave heating method.

The microstructures and properties of Al2O3-TiB2 composite coating on the surface of the aluminum alloy by reactive spraying was studied. The influences of mechanical alloying and spraying temperature on the phase constituent and microstructure of the composite were analyzed by X-ray diffractometry(XRD) and scanning electron microscopy(SEM). The results indicate that Al2O3-TiB2 composite coating is obtained by plasma spraying using milled powder of Al，TiO2，B2O and B2O3. The coating possesses high microhardness of 1300 HV0.1.

Boron-doped BaTi1-xB2xO3+X materials were prepared via organic chelating chemistry using alcohols as solvents/ligands. When sintered under air at 900 ℃, those materials were light-yellow colored, and yielded the dielectric properties comparable to those of pristine BaTiO3 sintered at 1300 ℃. However, they displayed blue/gray color after sinterd under Ar or a reductive atmosphere like 5%H2/Ar at T > 850 ℃, and the dielectric properties dramatically changed compared with the samples sintered under air, suggesting the transformation of insulating BaTiO3 into an semiconductor. By contrast, pristine BaTiO3 samples differed slightly in the dielectric properties when the sintering atmosphere was shifted from air to Ar or 5%H2/Ar. The possible mechanism of the “reduction” behavior in BaTi1-xB2xO3+X materials (the role of boron in reduction of Ti4+ to Ti3+ in BaTiO3 lattice) is under investigation.

Mo2FeB2 Cermet Coating was deposited on Fe substrate by react flame spraying (RFS) process. Three different groups of specimens were prepared according to the change of induction heating treatment time. Comparative study of phase composition, microstructure, interfacial microstructure and bond strength of Mo2FeB2 Coating was carried out. X-ray diffractometry (XRD) and Scanning electron microscopy (SEM) were used to characterize the Mo2FeB2 coating. The bond strength between the coatings and Fe substrates was measured with the pull-off test method according to the corresponding GB 8642-88 standard. Results indicated that the time of induction heating treatment greatly affected the microstructure, interfacial microstructure and bond strength of Mo2FeB2 coating. 13 seconds of induction heating treatment favoured the formation of a compact Mo2FeB2 Coating with the highest bond strength of approximately 60 MPa.

The microstructure and properties of ternary boride ceramic coating prepared by reactive flame spraying on surface of H13 steel are studied as well as the microstructures, microhardness, wear resistance and thermal fatigue resistance of the coating. The results show that the Mo2FeB2 cermet coating by reactive flame spraying has good wear resistance and thermal fatigue resistance and its microhardness can even reach 1200 HV.