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Zinc oxide with spherical shaped and flower shaped morphology are prepared by simple one step solvothermal method. The product is subjected to characterization to investigate the morphology and size by using X ray diffraction , semi electron microscopy and transmission electron microscopy. The size of the prepared zinc oxide particle is in the range of 1 micrometer to 3 micrometers. The outer surface of the particles is not smooth but it is rough. The possible formation mechanism for the product is investigated that is further justified by means of structural characterization.

The microstructure and tensile properties of the as-cast and as-extruded Mg-12Li-1Zn-xSn (x=1, 3, 5, 8, wt.%) alloys were investigated. The alloys are mainly composed of β-Li phase, Mg2Sn phase. With the increase of Sn content, the microstructure of as-cast alloys is refined. After extrusion processing, grain size is obviously refined, and the Mg2Sn phase is broken into tiny particles. The elevated-temperature tensile behavior of the alloy was investigated at 373~523k under the strain rate of 1×10-2~1.7×10-4s-1. The results indicate addition of Sn can improve the strength and plasticity, when the content of Sn is 5.0 wt.%, the as-extruded alloy possesses good superplasticity, which obtains the maximum elongation of 134.4% under a low strain rate of 1.0×10-3s-1at 523K.

Microstructure of electromagnetic pulse tungstic electrode argon arc welding (EMP-TIG) welded Mg/Al dissimilar metal joint is studyed using optical microscope, scanning electron microscope, and X-ray diffraction. The results indicate that gas tungsten arc welding can provide Mg/Al joint with excellent microstructure and performance. The welding region is composed of Mg3Al2 phase, α(Mg), β(Li), and MgAl. The weld zone and the Al alloy base materials are well combined. There are massive MgAl phase dendrites in the weld area, which cause the significantly increase of hardness at weld zone. Near the Mg-8Li alloy base metal side of the weld zone, there exists a layer of 100~ 200μm equiaxed region. About 1μm Mg3Al2 reaction layer is distributed between Mg-8Li alloy base metal and the equiaxed grains. This reaction layer and the Mg-8Li alloy base metal, as well as the weld zone of equiaxed grains, have a good combination.

Mg-8.5Li-1Al-1Ce alloys were prepared with vacuum induction melting method. Uniaxial rolling deformation of alloys was obtained by two-roll milling. The effect of rolling deformation was studied on the microstructure and mechanical properties of Mg-8.5Li-1Al-1Ce. The results show that the microstructure morphologies of α-phase, β-phase and Al2Ce-phase go through different changes under different rolling percentages, and the mechanical properties are improved with increasing deformation. Besides the basal slip system, the prism and pyramidal slip systems are also activated in α(Mg) phase, with all the slip systems in β(Li) phase being uniformly activated.

An Mg-Li-Al-Zn-Sn alloy was prepared by vacuum melting. The actual content of the elements in the alloy was determined using inductively coupled plasma-atomic emission mass spectrometry (ICP-AEMS). The density of the alloy was detected using Archimedes’ method. Extrusion and rolling deformation were carried out on this alloy. Its microstructures and mechanical properties were then studied with an optical microscope (OM), scanning electronic microscope (SEM), X-ray diffractometer (XRD), energy dispersive spectrometer (EDS), and tensile tester. The extruded alloy was composed of α-Mg and Mg2Sn phases and had good strength and elongation properties as well as a good comprehensive performance. After further rolling deformation, an Al-Li phase appeared due to atomic diffusion during the hot rolling process. Strain-hardening and the strengthening effect of the Al-Li phase further improved the strength of the alloy but decreased its elongation capacity.

Vicat softening temperature (VST) is one of the most important parameters to evaluate heat resistance of thermoplastic materials. However, the initial test temperature is difficult to control, which may reduce the testing efficiency and the precision of VST. Moreover, according to the procedure of GB/T 1633-2000, the specimen should be placed horizontally under the indenting tip of unloaded rod for 5min. After that, add a sufficient weight to the weight-carrying plate, and then set the penetration indicator to zero to start the experiment. However, the waiting period between adding the extra mass and starting the test may be different during the real operation. Such longer or shorter waiting periods can also influence the tested VST. In this paper, ultra-high molecular weight polyethylene (UHMWPE) was used to discuss the influence of initial temperature and waiting period on its final VST. The results show that, in order to satisfy the practices of standard GB/T 1633-2000, the initial temperature and the waiting period should not exceed 40°C and 25min, respectively.

The porous NiO/ samaria doped ceria (SDC) cermets, which have been used as the anode-supported for solid oxide fuel cell (SOFC), are fabricated via the tape casting process. In this article using different kinds of slurry system, prepared the large size (60×60mm) anode substrates for SOFC successfully. Effects of solvent, dispersant, plasticizer, binder and the sintering temperature program were investigated. Experimental results show that thicknesses and pore rates of anode substrates are 0.6 ~ 1.5mm and 20% ~ 40% respectively. And all of the complete and flat anode substrates have highly support intensity, for their homogeneous microstructure and pore distribution. Sintering the green pieces of anode substrates at the temperature of 1300°C for 2h, different green pieces have different shrinkages that could be from 20% to 30% measuring with thermal dilatometer. Using this kind of anode substrate, could find out a perfect one to matching the electrolyte film easily.