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In this paper, it can be seen that the optimum mixture ratio of graphite to other contents (graphite: H2SO4: H2O2: HClO4) is 10(g):28(ml):1(ml):5(ml), which obtained the best expansion voluSubscript textme (191ml/g). The Fe3O4-expanded graphite composite material was prepared by FeCl3 solution of ethylene glycol with heating reaction in reactor. The graphite sheets within EG were nanoscales, four iron oxide nanoparticles were dispersed between holes of expanded graphite sheets. Evidently, the graphite nanosheets wrapped in the four iron oxide particles can be observed. It is clearly that the magnetic adsorption properties of particles are strength on EG/Fe3O4. In addition, the EG/Fe3O4 composite obtained by this process has a product (magnetite), which is proved of XRD characteristic peaks.

Thermodynamics and dynamics of Mg3Zn6Y quasicrystals in solidification process were detailedly studied in this paper. The free energy, nucleation rate and nucleation energy were deduced and calculated. It shows that the driving force and nucleation rate gradually increase with the decreased temperature. The further studies show that the nucleation energy increase gradually with the decreased liquidus temperature. And it is apt to quasicrystal nucleation by increasing the cooling rate in a proper temperature range.

The influences of different hot working conditions on the microstructures and mechanical properties at weld zone of the Ti3Al/TC4 dual alloy have been investigated. The experimental results show that forging and heat treatment has significant influence on room temperature tensile strength (RTTS for short) of the weld zone. The influence of forging strain and temperature on its elongation at temperature 500ºC is also conspicuous. The results of intuitional and variance analysis show that affecting factors of its RTTS are heat treatment, forging strain, forge temperature and condition of billet in sequence. The affecting factors of its room temperature (RT for short) ductility and the tensile strength (TS for short) at temperature 500 ºC are forging strain, forge temperature, heat treatment and condition of billet. Good comprehensive properties are obtained under optimal conditions: forging at 1020ºC, annealing at 700ºC for 12 hours, air cooled, about 40% strain and as-rolled billet. The microstructures of the weld zone worked according as those conditions are uniform and the grain size is also fine.

Dissimilar joining of Ti-22Al-25Nb alloy and an α+β titanium alloy TC11 were carried out using electron beam process and linear friction process, respectively. The microstructure and tensile properties of the joints were investigated. The results show that both EBW and LFW could be adopted to the dissimilar joining of Ti-22Al-25Nb/TC11. The EB welded joint exhibits higher strength than that of the LF welded joint, due to the precipitation of O phase in the fusion zone of the former one. These results can be expected to be of great technical interest as basic data for the use of EBW or LFW in aerospace industry.