The influences of factors such as particle size (0.55？2.2 mm), particle velocity (15？35 m/s) and thickness of work material on the surface integrity were investigated. The residual stresses induced by shot peening or grit blasting were examined. In order to clarify the influences of those factors on residual stress included in the surface integrity, a medium carbon steel (w(C)= 0.45%, 180 HV) was peened by a centrifugal type peening machine using cast steel particles (650？800 HV). The results show that the compressive residual stresses on the peened surface are larger than those of grit blasting; the critical thickness of shot peening is about 50% thicker than that of grit blasting; the high compressive stresses induced by blasting are owing to the wrought or peening effect.

A quantitative study about the thermal activation of thermal donors (TD) in high resistivity magnetic Czochralski (MCz) silicon was carried out. The samples are p+/p/n+ diodes (active area 0.25 cm², thickness 300 μm) made of <100> MCz p-type Si wafers with the resistivity of about 2 kΩ？cm. The concentration of interstitial oxygen (O_i) in this material was measured by the Fourier transformation infrared (FTIR) spectroscopy method and it is 4.9×10¹⁷ cm^？3. The TD activation was performed through an isochronal thermal treatment at 430 ℃ up to a total time of 120 min. The space charge density after each annealing step was extracted from capacitance-voltage (CV) measurements. The TD generation can be utilized in processing of silicon detectors (pixel, strip and drift detectors) that are used e.g. in space applications, high-energy physics experiments, and several visual imaging applications. If the starting material is boron-doped p-type high-resistivity Cz-Si, the TD generation process can be utilized in order to produce p+/n-/n+ detectors. The last thermal process step, i.e. the sintering of aluminum, is intentionally carried out at the temperature where TD’s are created. Due to the generated donors, the p-type bulk will eventually be compensated to n-type bulk. Moreover, the full depletion voltage of detectors (V_fd) could be tailored between a wide range from 30 V up to almost 1 000 V by changing heat treatment duration at 400？450 ℃ from 20 to 120 min.

Aiming at the issues in quick processing and modeling design of drawing special-shaped tube die, by Conformal Mapping Theory and the numerical trigonometry method of interpolation between odd points and even points, the conformal mapping function is obtained. As the result, three-dimension drawing forming were converted into that of two-dimension problems, and the plastic stream function was analyzed, die cavity modeling and its optimized function were set up. Combining with modern processing technology, NC program and CAM of die cavity can be realized. Taking the drawing forming of hexagon tube with arc radii r and ellipse-shaped tube as instances, the drawing die cavity optimization of special-shaped tube was achieved, as well as, the changing principle of wall thickness was analyzed.

The biocompatibility of the hydroxyapatite/high density polyethtlene(HA/HDPE) nanocomposites synthetic auditory ossicle was evaluated, the percentage of S-period cells was detected by flow cytometry after L929 incubated with extraction of the HA/HDPE nanocomposites, titanium materials of clinical application as the control. Both of them were implanted in the animals and the histopathological evaluations were carried out, and the preliminary clinical trials about HA/HDPE nanocomposites synthetic auditory ossicles were also carried out. The statistical analysis show that there are no statistically significant differences between HA/HDPE test groups and control groups (P＞0.05), which demonstrates that the HA/HDPE nanocomposites synthetic auditory ossicle has a good biocompatibility and clinical application outlook.

In order to evaluate the effect of stoichiometric ratio upon electrochemical properties of AB₅-type hydrogen storage alloys, a series of alloys Mm_0.8La_0.2(Ni_4.0Mn_0.5Al_0.3Co_0.37Fe_0.13)_a (a=0.90？1.08) were prepared and the electrochemical properties were tested. Mm_0.8La_0.2Ni_4.0Mn_0.5Al_0.3Co_0.37Fe_0.13 was one of some new low cobalt AB₅-type hydrogen storage alloys which had been researched to have good electrochemical properties. The results show that the stoichiometric ratio has great effects on the electrochemical properties of alloys. And the effects were investigated in detail. When stoichiometric ratio x＜5.3, the activation performances of alloys are all good. But when stoichiometric ratio x＞5.3, the activation performances are decreased evidently. When stoichiometric ratio x＜5.3, the discharge capacities of alloys are linearly increased with the increase of stoichiometric ratio. When stoichiometric ratio x＞5.3, the discharge capacities of hydrogen storage alloys decrease linearly rapidly by the raise of stoichiometric ratio. Overstoichiometry is good to the cycle lives of alloys. When stoichiometric ratio is between 4.8 and 5.4, voltage platforms of alloys tend to increase linearly with the increasing of x. When x＞5.4, the increase of stoichiometric ratio leads to the decrease of voltage platform of alloys.

A multi-component polymer-coated molybdenum powder was chosen for selective laser sintering(SLS). The powder was prepared by coating polymer on Mo particles and frozen by grinding techniques. The laser sintering activities and sound densification response were obtained by optimizing the process parameters. The post-treatment process of SLS samples was developed, which was high temperature sintering Mo framework combined with Cu impregnation. Then, the Mo/Cu composites are gained. The microstructure evolution of post-treatment samples was investigated by scanning electron microscopy. Mo grains frequently string together. The microstructural characterization of Mo/Cu composites is homogeneous compound structure of adhesive phase Cu linked with Mo grains. There is little ellipsoidal Mo grains singly existing around Cu phase. Between Mo grains and Cu zone, there is a medium changing zone with width of 10？20 nm. Post-treatment mechanism is Mo framework sintering of solid phase and Cu impregnation of melting/solidification. The mechanical and thermal properties concluding tensile strength, elastic modulus, elongation and linear expansion of Mo/Cu composites were studied.

The flow stress feature and microstructure evolvement of a commercial pure aluminum were investigated by compression on Gleeble-1500 dynamic materials test machine. Optical microscopy (OM) and transmission electron microscopy (TEM) were applied to analyze the deformation microstructure of the commercial pure aluminum.The results show that the flow stress tends to be constant after a peak value and the dynamic recovery occurs when the deformation temperatures is 220 ℃ with the strain rate of 0.01 s^？1; while the dynamic recrystallization occurs when the deformation temperature is higher than 380 ℃, and the flow stress exhibits a single peak at 460 ℃ with different strain rates from 0.001 s^？1 to 1 s^？1, and continuous dynamic recrystallization and geometric dynamic recrystallization occur during the hot compression of the commercial pure aluminum.

Uniform nanocrystalline SnO₂ with different particle sizes was prepared by a solvothermal method using SnCl₄×5H₂O as the starting material and ethanol as the solvent in the presence of different concentrations of HCl or KOH. The as-prepared powders were characterized by X-ray diffraction(XRD), transmission electron microscopy(TEM), thermo-gravimetry and differential thermal analysis(TG-DTA), and nitrogen BET measurements. With increasing alkalinity of the precursor solution, the crystallite size of the as-prepared SnO₂ nanocrystals decreases from 7.1 nm to 3.2 nm, while the specific surface area of the as-prepared powders increases from 101 m²/g to 195 m²/g. When calcined at 500 ℃ for 2 h in air, the crystallite size of the as-calcined powders increases slightly (12？5.9 nm) and the specific surface area of the as-calcined powders is 42？63 m²/g.

LiFePO₄ thin films were prepared by sol-gel technique. The phase and surface morphology were characterized by X-ray diffraction and scanning electron microscopy. The electrochemical properties of the thin films were measured by cyclic voltammetry, galvanostatic charge-discharge experiments and electrochemical impedance spectroscopy in 1 mol/L LiPF₆/EC-DMC solution using lithium metal as both counter and reference electrodes. The films prepared by this method are of pure LiFePO₄ phase. The capacity of the film annealed at 700 ℃ for 30 min is 145 mA？h/g, and the capacity loss per cycle is 0.06% after being cycled 50 times. The electrochemical impedance spectroscopy shows that the diffusion rate of lithium ion in LiFePO₄ thin film is 5.1×10^？14cm2/s.

Using ploughing-extrusion process, the V-shaped capillary micro-grooves based on the surface of copper strip with thickness of 0.4 mm were obtained. When the ploughing depth is 0.3 mm and the groove interval is 0.24 mm, the groove width of the obtained structure is about 200 μm, the groove depth is above 400 μm, and the angle of grooves is less than 30？. The formation mechanism of ploughing-extrusion was analyzed using scanning electron microscope (SEM). The results show that the formation process consists of four steps, i.e. splitting-ploughing, extruding, forming and truing. There exist two critical states during the formation process. In the first state, a smooth U-shaped groove appears between two V-shaped grooves, and the compounded structure which comprised of V-shaped grooves and U-shaped grooves is obtained. In the second state, the U-shaped groove is evolved into a narrow crack, and the resulted V-shaped capillary macro-groove structure contains symmetric V-shaped grooves and narrow cracks. These two critical states are restricted by the groove interval (w) and the ploughing depth (a_p), and related on the tool parameters simultaneously.

The formation mechanism of bulge on the work’s surface during the extrusion process was analyzed. The bulge’s size and the reasons for abscission were studied. The results show that the abscission of bulge from works is resulted from the integrated actions of pressure and friction between the plough tool and works. During the extrusion-plough process, it is noticed that four kinds of fins are appeared, which are gestation fin, multi-dimensional fin, tumor and overlap fin, when using different machining parameters. And multi-dimensional fin which has high heat transmission efficiency is a kind of complicated fin with cockscomb-like 3D substructure fin on the tip of 3D macrostructure fin. Based on the studies of those four kinds of fins, the conditions of their formation are concluded, as well as the formation mechanism is obtained.

The technique of solution deposition was employed to prepare Li₄Ti₅O₁₂ thin film using lithium acetate and TiO(C₄H₉)₄ as starting materials. The structural and electrochemical properties of the thin films were studied by X-ray diffraction, cyclic voltammetry, galvanostatic charge-discharge experiments, and potential step technique. The results show that the thin film prepared by this method is of pure phase with a spinel framework structure. The capacity of the thin film annealed at 750 ℃ for 1 h is approximately 57 μA？h/(cm²？mm). The film possesses excellent cycling behavior with a 0.08% capacity loss per cycle after being cycled 50 times. Potential step technique shows that the average chemical diffusion coefficient of lithium ion in the thin film is approximately 4.5×10^{？11 cm2}/s.

A novel double metal cyanide complex (DMC) based on Zn[Ni(CN)₄] was prepared using K₂[Ni(CN)₄] and ZnCl₂, and employed as catalyst for the copolymerization of carbon dioxide and propylene oxide (PO). The resulting copolymers were characterized by IR, ¹HNMR. The results show that this catalyst exhibits catalytic efficiency at approximate 500 g copolymer per gram of Zn[Ni(CN)₄] under proper conditions. The mole fraction of CO₂ for copolymer can reach about 0.3. Propylene carbonate is also produced as by-product, but its content is as low as 4%？6% of overall products under suitable conditions.

Sn-Al-P-B composites were synthesized by novel rheological technique. The microstructure, morphology, and electrochemical performance of the materials were investigated by X-ray diffraction, scanning electron microscopy and electrochemical methods. The particles of tin oxide-based materials form an interconnected network structure like mesoporous materials. The average size of the particles is about 150 nm. The material delivers a charge capacity of more than 570 mA？h/g. The capacity retention of the material is about 95.5% after being cycled 30 times. The good electrochemical performance indicates that this kind of tin oxide-based material is promising anode for lithium ion battery.

The true stress—strain curves of compressed ZK60 alloy have two typical characters. Most thermal simulation compressing curves of ZK60 have the obvious character that around 0.2 in strain the stress reaches the peak and declines rapidly afterwards and lands the lowest. The decline of the curve illustrates that the test specimen has been destroyed and crackles can be found on the test specimen correspondingly. And the other true stress increases to a peak and then decreases to a steady state, indicating that dynamic recrystallization has occurred in ZK60 alloy. From the analysis of the results we can receive the optimized composite of the deformed parameters and get the reasonable deformed temperatures to be 200 ℃ or 400 ℃, which can play a directing role in determining the deforming technology of wrought magnesium alloys.

A phase-field model was established for simulating pure materials, which was calculated effectively and taken into account the strong anisotropy of kinetic and highly anisotropic interfacial energy. The anisotropy (strong kinetic and highly interfacial energy) of various degrees was simulated with numerical calculation. During a variety of interfacial anisotropy coefficient, equilibrium crystal shape varies from smoothness to corner. There has a critical value during the course of the transformation. When the anisotropy coefficenct is lower than the critical value, the growth velocity v increases monotonically with the increase of it. Whereas the anisotropy coefficent is higher than the critical value, the growth velocity decreases with the increases of it. During a variety of degree of supercooling, the growth velocity is under control from thermal diffusion to kinetics. Under the control of thermal diffusion, the growth velocity increases with the increase of degree of supercooling and tip radius R decreases with the increase of temperature. Under the control of kinetics, with the increase of degree of supercooling both V and R, which can not fit the traditional microcosmic theory.

This is a synthetical report about hydrogen behavior in titanium aluminide alloys in our group. There are two kinds of hydrogen solubility in titanium aluminides, one is the overall solubility at high temperature in the matrix without hydride and the other is the terminal solubility at low temperature in the matrix in equilibrium with the hydride. The former decreases but the later increases with increasing temperature. Hydrogen as a temporary β stabilizer clearly decreases the size of the α₂ phase, and increases greatly the amount of β phase, and then increases evidently the mechanical properties of Ti₃Al+Nb. The cathodic corrosion of TiAl during charging is due to hydride on the surface. The decrease of the strength, the strain to fracture and fracture toughness for hydrogenated samples is due to hydride. The enrichment of atomic hydrogen at the crack tip during charging under sustained load can enhance localized plastic deformation and cause hydrogen-induced delayed cracking.

The microstructure and mechanical properties of AZ80 alloy were investigated during thermal processing. The samples of 4 mm in thickness machined from cast ingot were compressed at 300 ℃ with a thickness reduction of 75% and cooled in the water to room temperature. Then ageing(T5) and solution+ageing (T6) treatments were employed respectively. The results show that mechanical properties are significantly improved after thermal processing than those of as-cast AZ80 alloy due to grain refinement and discontinuous precipitates. The heat treatment has significant influence on microstructural evolution for sample formed at moderate temperature. Microstructural evaluation indicates that the β-phase increases because of sufficient solution and the alloy is strengthened evidently.

With the microscopic phase-field model, the precipitation process of aged alloys was explored by computer simulation, which could clarify some discussional views on the precipitation mechanisms of alloys. The precipitation process of Ni₇₅Al_2.5V_22.5 alloy was studied. From the simulated atomic pictures, calculated order parameters and volume fraction of different precipitates, it’s found that the θ ordered phase precipitates earlier than γ′ ordered phase by congruent ordering+spinodal decomposition mechanism and thus produces a nonstoicheometric θ single ordered phase. Then, the nonstoicheometric γ′ phase is precipitated by a non-classical nucleation and growth mechanism at the APBS of θ phases. Meanwhile, both of them transform to stoicheometric ordered phases.

Through the addition of rare earth oxides into the coating of electrodes, the high temperature oxidation and sulphidation resistance of weld metal were studied. The transfer mechanism of rare earth oxides from coating to the welding pool and the physicochemical reaction during the process were analyzed. With the application of scanning electron microscope and energy spectrometer, the mechanism of weld metal corrosion in air and sulphur environment were studied. The result shows that the addition of rare earth oxides can improve the high temperature resistance of weld metal, especially in sulphidation environment. The electrodes in which La₂O₃ is added have better performance than the electrodes in which CeO₂ is added. The existence form and distribution characteristic of rare earth are defined. It is believed that the marked effect of rare earth oxides in sulphur environment is related to the corrosion mechanism.

The different aging process was investigated for ZK60 magnesium alloy to get the ideal synthetic properties. The results show that the values of strength, hardness and plasticity of ZK60 magnesium alloy increase at first and then decrease with increasing aging temperature, the suitable aging temperature of ZK60 alloy is from 160 to 180 ℃. At the meantime, the microstructures of appear mesh texture under high ageing temperature, this is the main reason why the mechanical properties decrease.

Based on the continuum equation, momentum conservation and energy conservation equations, the numerical model of turbulent flow filling was introduced; the 3-D free surface vof method was improved. Whether or not the numerical simulation results are reasonable, it needs corresponding experimental validations. General experimental techniques for casting fluid flow process include: thermocouple tracking location method, hydraulic simulating method, heat-resistant glass window method and X-ray observation etc. The hydraulic analogue experiment with DPIV technique is arranged to validate the fluent flow program for low-pressure casting with 0.1×10⁵ Pa and 0.6×10⁵ Pa pressure visually. By comparing the flow head, liquid surface, flow velocity, it is found that the filling pressure value influences the flow state strongly. With the increase of the filling pressure, the fluid flow state becomes unstable, the flow head becomes higher, and the filling time is reduced. The simulated results are accordant with the observed results approximately, which can prove the reasonability of our numerical program for filling process further.

Bismuth oxide has wide applications in superconductive material, photoelectric material, electronic ceramic, electrolyte, and catalysts. To produce ultrafine bismuth oxide powders, some costly heating sources, such as plasma, high frequency induction, electron beam or laser, have to be used in the conventional vapor oxidation methods. The vapor oxidation method was improved by adding a reducing agent in the reaction system, where heating source was resistance tubular oven, instead of special heat source requirement. Nanometer bismuth oxide was prepared at 1 000？1 140 ℃, and the particle characteristics were investigated by XRD, SEM, DTA, laser sedimentograph. With low oxygen concentration (less than 20%) in the carrier gas, the bismuth oxide particle was near-sphere β-Bi₂O₃ with uniform and fine particle size (d_0.5=65 nm, GSD=1.42); while with higher oxygen content (more than 50%), the powders were mixture of Bi₂O₂CO₃ and β-Bi₂O₃.