Shell/core-type MnO-coated Ni nanoparticles was prepared by arc discharge method using micron-sized Ni and MnO2 powders as the raw materials, and the evaporating atmosphere was a mixture of hydrogen and argon. The morphology, structure and chemical composition of the as-prepared nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermal gravity analysis (TGA), respectively. It was showed that most of nanoparticles were in spherical shape in the range of 30-60 nm, with a shell of MnO phase and a core of Ni. The formation of nanoparticals was effectively explained by an extended mechanism of the Vapor-Liquid-Solid (VLS) with the existence of stoichiometric oxygen. The Ni core plays an essential catalyst in the formation of the core/shell structure.

The blended resin systems of bisphenol A epoxy resin E-44 and silicone-epoxy resin ES-06 were UV cured．And then the atomic oxygen (AO) exposure experiments were carried out．The changes in surface composition and morphology of the polymer sample before and after AO exposure had been followed by scanning electron mictrscoly (SEM) and X-ray photoelectron spectroscopy (XPS). The mechanism of the interaction of AO with the photopolymerized silicon-containing polymer was discussed. The results show that the sample surface had been incompletely oxidized to a silicon oxide (SiOx )film after UV irradiation polymerization． Based on SEM and XPS data， it may be proposed that AO exposure of the materials produces a SiO2 film at the surface of the sample, which can protect the underlying polymer from AO erosion．The mechanism of interaction of AO with the polymer is mainly chemical reactions involved H-abstraction, replacement or bond, leading to remove the organic portions of the polymer as volatile products and leave a silicon oxide surface coating.

The influence of thermohydrogen treatment (THT) on microstructural evolution and hardness of Ti600 alloy has been studied. The microstructural evolution of Ti600 alloy after THT have been investigated and analysed by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and the influence of THT on the hardness of Ti600 alloy has been analysed by hardness testing. The microstructural observation reveals that there are two types of silicides precipitate in the Ti6oo alloy after THT, one is tetragonal silicide S3 (0.357 wt.% H), and the other is hexagonal silicide S1 (0.497 wt.%). Hydrides δ (fcc structure) exist in the specimens with 0.357 wt.% and 0.497 wt.% hydrogen, and hydride δ tends to be refined with increasing of hydrogen. The result of hardness testing shows that the hardness of Ti600 alloy increases with increasing of hydrogen. Additionally, the influence mechanisms of THT to the hardness of Ti600 alloy are discussed, and it is considered in this paper that hydride δ, silicide and lattice defects are the major factors leading to the hardness of Ti600 alloy increase with increasing of hydrogen.

In this study, superplastic tensile tests were carried out for Ti-6wt%Al-4wt%V alloy at temperatures of 700℃～850℃with initial strain rates of 3×10-4～5×10-3s-1. The tensile results show that Ti6Al4V alloy exhibit good low temperature superplasticity. The elongation of 536% was obtained at 800℃ with an initial strain rate of 5×10-4s-1, and the elongation over 300% were obtained even at a temperature of 700℃ (with an initial strain rate of 5×10-4s-1). The strain rate sensitivity values m kept about 0.3 in the whole deformation temperature range, and the maximal m value was 0.55. At the temperature range of 800～850℃, the deformation activation energy was very close to self-diffusion activation energy of grain boundary, which shows the main deformation mechanism is grain boundary sliding controlled by grain boundary diffusion. Yet, at the temperature range of 700～750℃, the deformation activation energy was much higher than the self-diffusion activation energy of grain boundary. The reason may be dynamic recrystallization and active dislocations motion.

Ultrafine ferrite grains with size about several hundred nanometers were obtained through tempering the cold rolled martensite in a low carbon and in a microalloyed steel bearing Nb, V and Ti. In this paper, the mechanism for the formation of the ultrafine grained microstructure was discussed. Dislocation cell structures formed in martensite during cold rolling were developed into ultrafine ferrite grains with sharp and large misoriented boundaries during tempering at temperatures from 500℃ to 600℃ for 60 minutes. During the tempering process, microalloying precipitates formed and effectively pinned the dislocation movement and the migration of the grain boundaries. As a result, the thermal stability of the ultrafine grained microstructure is improved.

There has been a wide attention in nanocomposite coatings with interface phases because of their superhardness, but the limitation hardness that this kind of materials can achieve was still an argued question by many researchers. In this paper, we observe the limitation hardness of nanocomposite coatings is very sensitive to microstructure of interface. It is shown that a dependent relation between hardness and oxygen impurity content of coatings resulted from our experiments. Based on an atomic model analysis, the decreasing of hardness caused by a small amount of oxygen impurities can be explained by oxygen atoms induce weakening of the Si3N4 interface which acts as a “glue” between the TiN nanocrystals. Further, we conclude that density of oxygen atoms around grain boundary is a dominant factor on hardness degradation of the films

Polyborosilazane (PBSZ), a precursor to SiBNC ceramic, was synthesized via cocondensadition approach using methyldichlorosilane (MeHSiCl2), boron trichloride (BCl3) and hexamethydisilazane (HMDZ) as the starting materials. SiBNC ceramics were obtained when pyrolysising the as-synthesized PBSZ in NH3/N2 atmosphere. The chemical composition, structure and high temperature properties of the obtained polymer and ceramics were investigated using EA, FTIR, NMR, XPS and XRD. The results indicate that the backbone of PBSZ is －Si－N－B－ linkage in the form of borazine and C is in the form of Si－CH3. The ceramic yield of the PBSZ at 1000 ℃ in NH3/N2 atmosphere is 61％. The products have low carbon content (<0.5％)and show excellent high temperature stability. They are fully amorphous after heated to 1700 ℃ and result in partially crystallized Si3N4、BN、SiC phases when heated to 1850 ℃.The weight loss of SiBNC ceramics at 1500 ℃～1850 ℃ is about 10％.

Equal channel angular pressing and cold rolling (ECAP+ CR) were carried out in commercial pure (CP) Ti by combining ECAP and traditional deformation. Microstructure and mechanical properties of as-deformed Ti were studied. The results show that, after ECAP+CR, grains are significantly elongated and formed into fibrous tissue; for the CP Ti processed by ECAP and a higher rolling strain of 55%, its yield strength and ultimate strength reach to 715MPa and 805MPa, respectively, while maintaining good ductility of 16.8%, the mechanical properties are closed to that of Ti-6Al-4V.

Lead zirconate titanate (PZT) (52/48) powders were synthesized by Wet-acoustic chemical method. XRD results show that the perovskite phase of PZT is formed under 400℃, which is much lower than the calcinations temperature (500-900℃) require in other reaction process. Phase-pure PZT powders were obtained at 700°C. SEM results show that the powder particle is round and its size is within 1μm.

The paper studied electrochemical performances of amorphous carbon nanotubes (ACNTs) as anode materials of lithium ion battery. The results indicate that as-grown ACNTs possess the initial reversible capacity 305mAh/g under the charge-discharge condition of 20mA/g The oxidization treatment at the temperature range of 300~450℃ increases the capacity of Li intercalation due to decreasing nanoparticles and amorphous carbon and improving the surface activation of ACNTs. The first reversible capacity of ACNTs oxidized at 300℃ is up to 530mAh/g and the cycle life is well.

Using powder metallurgy technology, the system of (FeV+graphite) finished carbonized reacts and VC iron matrix composite fabricated in situ in vacuum furnace. SEM，XRD and TEM were used to examine the structure and phase of composite. The wear-resistance of VC iron matrix composite was examined on a MM-200 wear-test machine. It was confirmed that graphite reduced the stability of σ-（FeV）, and σ-（FeV）decomposed small quantity of α-Fe and V at 1073K.The composite was mainly made of VC particles and α-Fe, and displayed good wear-resistance under dry sliding with heavy load.

A TC6 titanium alloy coating with columnar microstructure was prepared on the substrate of TC6 titanium alloy by pulse laser cladding successfully and studied by SEM, XRD and EPMA. The results showed that, the microstructure of the coating showed a typical columnar characteristic. The coating was still composed of α′ martensite which was finer than that of conventional heat treatment or welding. The distributions of main alloying elements were more homogeneous in columnar structure than in substrate. With the solidification theory and calculated results of temperature gradient (G) and solidification velocity (R) at the solidification interface, the formation of columnar structure was studied. The columnar structure was formed in the transition of “liquid phase→ β phase” and determined by G/R ratio at the solidification interface. In cooling process, the morphology of columnar β-phase was retained. With the variety of G/R ratio at the solidification interface, the morphology of the columnar structure varied and finally transformed to other structures.

Among the advanced composites reinforced by high-performance fibers, the plastic reinforced by short carbon fibers is remarkable by its variety of performance and lower cost. By synthesizing the preceding productions, the strength rule-of-mixture of short fiber reinforced composite is educed, and the modified formula is obtained by using the length coefficient to correct the asymmetry of stress distribution in material. The math model is established to estimate the influence disciplinarian on strength of parameters. By taking carbon fiber reinforced PTFE composite as the example, the strength forecast method is explained, and it will provide the reference to new material usage and new structure design.