To clarify the fracture mechanism of metal cylinder under explosive loading, HR2 steel cylinders with shell of 6 and 12 mm in thickness respectively were subjected to explosive loading. The fracture fragments were collected after explosion, and then systematically investigated in terms of macroscopic morphology, fracture morphology and deformation microstructure. It is found that when the shell thickness increases, the fracture mode of HR2 cylinder changed from shearing fracture to the mixture of shearing fracture and tensile fracture. The deformation microstructure observation indicates that the failure and fracture of cylinder shell are the result of the combination and competition of cracks-nucleating and -expanding from the shear band and from the outer surface. The fracture of thin cylinder is dominant by the cracks nucleating and expanding from the shear band, presenting shearing fracture mode. The fracture of thick cylinder is the combined action of cracks-nucleating and -expanding from the shear band and from the outer surface, presenting a mode of mixture of shear- and tensile-fracture.

The microstructure and mechanical properties of the longitudinally profiled EH40 steel plate with the specification of (30~50) mm×2600 mm×3000 mm were investigated by means of tensile test, impact test, hardness test, optical microscope and TEM. Results show that the microstructure and mechanical properties of the longitudinally profiled steel plate is diverse due to the experienced different processes of the thin end and thick end. As the thickness of the steel plate increases the yield strength decreases from 534 MPa to 489 MPa, while the tensile strength decreases from 599 MPa to 569 MPa. When the impact temperature is -60^oC, the absorb energy is over 200 J for the thin end of steel plate, while the absorb energy fluctuates for the thick end. The grains of the thick end with lower bainite content are larger than those of the thin end. There is Bainite within the full cross section for where with the plates of 30 mm and 40 mm in thickness. However, all the bainite disappeared for where with the plates of 8 mm and 50 mm in thickness. The precipitated phases of both the thin ends and thick ends are (Nb, Ti)C. For the plate at the thin ends, there exists large amount of precipitated phases with small particle size, whereas small amount of precipitated phases with large size for that at the thick ends.

The coordinated plastic deformation, nano-lamination and amorphization in the friction-induced layer of lath martensite steel were characterized via transmission electron microscopy (TEM) observation on samples prepared with fixed-point ion beam cutting (FIB). It was found that high-density dislocation and defects concentrated in nano-lamellar structures. The amorphous structures formed at interfaces between nano-lamellar structures in friction-induced layer under high strain. These amorphous products may be beneficial to the further refinement of the wear debris and thereby the formation of a protective layer. According to the above experimental results, an amorphous nucleation model in dry sliding friction process was established based on tribology- and material-theory, and then the thermal conditions and energy barriers for amorphization were calculated. The results show that the amorphous nucleation energy model in dry sliding friction established according to the classical nucleation theory and the Gibbs free energy barrier calculation formula can be used to calculate the necessary critical dislocation density value for amorphization. According to the calculation results, the solid-state amorphization of the lath martensite can be induced by the dry sliding friction strain under the optimal friction condition.

Amorphous Co-W-B was deposited on carbon cloth (CC) to fabricate a self-supported Co-W-B/CC composite electrode by using chemical reduction method. Electrochemical analysis show that Co-W-B/CC materials exhibited excellent electrocatalytic performance for electrolysis of water in 1 mol/L NaOH solution. Among others, the Co-50W-B/CC (the ratio of [WO₄^2-]/([WO₄^2-]+[Co²⁺]) is 50% in the synthesis process) shows the best electrocatalytic activity, i.e. for the Co-50W-B/CC catalyst, when the low overpotential is 0.394 V by ampere density of 10mA/cm², the corresponding Tafel slope is 96.8 mV/dec for the oxygen evolution reaction (OER), whilst when the overpotential is 0.098 V by ampere density of -10 mA/cm², the corresponding Tafel slope is 117.4 mV/dec for the hydrogen evolution reaction (HER). EIS analysis result implies that the Co-50W-B/CC possesses nearly the same catalytic activity as the noble metal-based materials at low current density, which can mainly be attributed to both the high intrinsic catalytic activity and the large electrochemical active area.

Two kinds of spin valve composed of multilayered films of Ta/CoFe/Fe/Au/Fe/IrMn/Ta and Ta/CoFe¹/Au/CoFe²/IrMn/Ta were deposited respectively on oxidized silicon wafer by high vacuum magnetron sputtering. Their magneto-resistor characteristics and magnetization reversal fields were tailored by selectively adjusting the processing parameters for each of the function layers. The microstructure and thickness of the multilayered films were characterized by means of TEM. The hysteresis loops and magneto resistance (MR) curves were measured by VSM and four-probe measurement tests. Results show that there exists a relationship of vibration attenuation for the MR values with the thickness of the middle isolation layer Au. Namely, with the increase of the thickness of the Au layer, the vibration attenuation weakened. The coercive force and saturation magnetization of the multilayered films were determined by the thickness of each different function layers, which then alter the MR values directly. There was a best MR value for the multilayered structure of Ta/CoFe¹/Au/CoFe²/IrMn/Ta with the following film thickness for each layer: 6/6/3.8/6/9/6 nm.

Al-based superhydrophobic material with excellent wear resistance were prepared by hydrothermal method. SEM results reveal that there exists a distinct micro-nano hierarchical structure on the surface of the prepared material. After 2,000 cycles of friction test the surface of the prepared material became slightly smooth, but where a large number of ZnO nanorods still remained, which maintains superhydrophobic properties yet. Also, the Al-based superhydrophobic material has good resistance to acid- and alkali-corrosion. Condensation experiments shown that condensate droplets will be randomly generated on the micro-nano hierarchical structure. It is worth noting that the condensate droplets in the groove will gradually get out of the bottom of the groove during the growth and coalescence processes, and finally suspended on the surface. It confirmed that the condensate droplets remain in the Cassie state, which provides a guarantee for the frequent occurrence of self-propelled of condensate droplets.

The ZnO-based varistor ceramics with addition of different amount of Bi₂WO₆ were prepared by conventional solid state reaction and then their surface morphology and electrical properties were examined. Results show that appropriate Bi₂WO₆-dopping can promote the uniform growth of ZnO varistor ceramic grains, improve their uniformity of microstructure, reduce the breakdown voltage and increase the nonlinear coefficient. In addition, Bi₂WO₆ can increase the content of absorbed oxygen on the surface of ZnO, thereby enhance the density of the interfacial state and barrier height, correspondingly, optimize the nonlinear characteristic of ZnO varistor ceramics. For the ZnO-based varistor ceramics with x=7% (mass fraction) Bi₂WO₆, presents excellent properties: the nonlinear coefficient α is as high as 53, corresponding to the highly barrier height φ_b of 11.52 eV, whilst the leakage current J_L and the breakdown voltage are as low as 3.50 μA/cm² and 263 V/mm, respectively.

The effect of particle size-grading and the packaging with various insulating agents on the properties of amorphous magnetic powder cores was investigated. Firstly, the variations of compression density, magnetic permeability, loss and DC biasing capability of amorphous magnetic powder cores were studied by changing the particle size-grading of amorphous powder. It was found that with magnetic powder of particle size-grading as 10%, 30%, 30% and 30% for particles with size in between -140~+170, -170~+200, -200~+350 and -350 ~+1000 mesh respectively, the compacting density of the amorphous magnetic powder cores increased, thereby the DC biasing capability increased, while the magnetic loss decreased. Secondly, different insulating agents were used to encapsulate the amorphous magnetic powder cores. The results show that using phosphoric acid as insulating agent can reduce the magnetic loss and improve the DC biasing capability more effectively than using water glass as insulating agent. Thirdly, low-melting glass frit not only acts as an insulator in the amorphous magnetic powder cores but also acts as a binder. Finally, the magnetic properties of the amorphous magnetic powder cores prepared by using the powder of recycled waste amorphous iron cores are not significantly different from those prepared by using the powder of the ordinary iron silicon boron alloy.

Nano-SnAgCu solder of low melting point was prepared by means of microemulsion method. The effect of different surfactants, Sn-precursors and the ratio of microemulsion on the melting temperature of the prepared particles of nano-SnAgCu solder was systematically investigated. Results show that the lowest initial melting temparture, 183.6^oC was acquired for the particles of nano-SnAgCu solder prepared via the process with optimal processing parameters, namely the prepared Sn3.0Ag0.5Cu solder presents a melting point of 183.6^oC, which is close to 183^oC of the lowest melting point of SnPb solder, while is c.a. 32.2^oC below that of the commercial solder paste (217.8^oC).

Friction materials were prepared based on a simple formulation with six ingredients (phenolic resin, aramid pulp, nano sodium titanate whisker, alumina, barite, molybdenum disulfide). Hardness, impact strength, friction coefficient, wear rate, and morphology of sliding surfaces were carefully examined to investigate the effect of the two different fibrous ingredients, i.e. aramid pulp and nano sodium titanate whisker, in the friction material on various physical and mechanical properties and friction properties. The results show that the Rockwell hardness of friction material increased with the increase of the content of aramid pulp in the formula. When the ratio of aramid pulp to sodium titanate whisker is 3:1, the maximum impact strength of the material reached 0.392 J/cm². The uniform mixing of two reinforcing fibers provided a basis for the formation of high cohesion friction film during the friction process. When the ratio was 0.75, the best synergistic effect was obtained. At this time the friction coefficient was stable between 0.38 and 0.45, and the wear rate was 5%.

The BiOCOOH with multi-layered structure was synthesized by hydrothermal method, and then was used as sacrificial precursor to prepare several different products through adjusting heat treatment temperatures, including a new type of composite photocatalytic material β-Bi₂O₃/BiOCOOH with visible light response. The crystal structure, optical absorption performance, morphology, photocurrent and other physical and chemical properties of the products were characterized by means of X-ray diffraction (XRD), UV-Vis DRS, scanning electron microscope (SEM), photoelectric chemical response and other characterization methods. Their photocatalytic activity was assessed via degradation test of Rhodamine B solution. The results show that when the heat treatment temperature gradually increased from 250℃ to 330℃, 400℃ and 450℃, the following transformation occurred: BiOCOOH→β-Bi₂O₃/BiOCOOH→β-Bi₂O₃→α-Bi₂O₃. The visible light catalytic performance of the composite photocatalyst β-Bi₂O₃/BiOCOOH is the best. The degradation rate of Rhodamine B in the presence of β-Bi₂O₃/BiOCOOH composite photocatalyst was 6.7 times and 100 times higher than those in the presence of β-Bi₂O₃ and α-Bi₂O₃, respectively. The samples that showed the best decolorization rate for rhodamine B had a mineralization rate of 88% within 90 minutes of illumination. Electrochemical test results show that the composite β-Bi₂O₃/BiOCOOH has a larger photocurrent response and a smaller impedance than the plain materials β-Bi₂O₃ and BiOCOOH. In addition, by considering both of UV-Vis DRS and Mott-Shottky curves comprehensively, the positions of conduction and valence bands of β-Bi₂O₃ and BiOCOOH can be estimated respectively, and it is speculated that β-Bi₂O₃ and BiOCOOH can be closely combined to form z-type photocatalytic structure, thus having higher separation efficiency of photogenerated carriers and effective separation of photogenerated charges.