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The paper uses the preprocessor of ANSYS to generate the model of 3D entity and mesh generation on WW0.8/10 air compressor crankshaft. Mesh generators are transferred into data that will be used in finite element analysis. Passing by dealing with force and commitment, it calculates the forces of pressure working conditions of crankshaft. They are used in stress analysis. The stress data is calculated from the calculator of ANSYS. The static load safe coefficient and the fatigue safe coefficient of the crankshaft are tested from known stress. The result provides a high reference value for the optimization improvement of the crankshaft.

The sub-rapidly solidified Au-20Sn eutectic alloys were prepared by four different solidification pathways, such as, graphite mold conventional casting, graphite mold injection casting, copper mold injection casting, and water-cooled copper mold suction casting. The precipitating sequences of competing primary phases of sub-rapidly solidified Au-20Sn alloys with four different cooling rates were investigated. The results show that phase selection process is related to the cooling rates during sub-rapid solidification process. The primary ζ'-Au₅Sn phase with developed dendrites precipitate at low cooling rate (2.4×10−4.2×10² K/min) and the morphologies of the primary ζ'-Au₅Sn change to rosette-like at higher cooling rate (9.0×10³ K/min). While the cooling rate reaches to 3.5×10⁴ K/min, the primary ζ'-Au₅Sn phase can be suppressed but δ-AuSn phase will precipitate prior to the ζ'-Au₅Sn phase. On the basis of the classical nucleation theory and transient nucleation theory, the process of competitive nucleation between the ζ'-Au₅Sn phase and the δ-AuSn phase were analyzed for sub-rapid solidified Au-20Sn alloy. The theoretical calculations are consistent with the experimental investigations.

SNCR (Selective Non Catalytic Reduction) system is proposed, with 40% methylamine aqueous solution as reducing agent to reduce NOx in diesel exhaust gas. The effect of injection position and volume on the reduction efficiency through the test bench is systematically researched. A three-dimensional model of a full-sized diesel SNCR system generated by CFD software FIRE is used to investigate the reduction efficiency under different temperatures. The simulated results have a good agreement with the test results, and it can be used to optimize SNCR system. The results can indicate the practical application of this technology.

Anodic oxidation in situ preparation of titanium matrix TiO2 nanotube and optimize the preparation process parameters. With the help of X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) technology we characterized the light catalyst that we have prepared. By oxidation degrading methylene blue, we tested its light catalytic activity. The result showed that the TiO2 nanotube maded at 20 V anodizing voltage, ionic liquids (2 ml), ammonium fluoride (0.684 g), ethylene glycol volume (200 ml) and water volume (6 ml)after 20 h, after dried for 30 min under 105 oC and annealed for 1 h under 500 oC in air became anatase phase, and the ratio of rutile phase is very low. The TiO2 nanotube arrays we made under the above condition for the degradation of methylene blue are good. The average diameter of a nanotube is about 90 nm, and the average thickness of a nanotube’s rampart is about 10 nm.

In order to study the effect of rock fracture distributions on stability of tunnel, the effect of joints with different strike dip, the size and density was considered by using probability and statistics method. Based on the Monte Carlo random simulation, the statistical network model of 2D jointed rockmass was established to describe and characterize jointed rock mass. On the basis of this, the numerical code RFPA2D is employed to analyze effect of fracture dip angle on the tunnel stability. Numerical results show that the fracture distribution has a little effect on tunnels failure mechanism and failure type of tunnel because the failure of tunnel in the jointed rockmass is similar to the one without joints and fissures. However with the change of the fracture dip angle, the loading capacity of the tunnel in the jointed rockmass varies accordingly.

In this paper the TiNi/Ti2Ni composite powders has been synthesized by the chemical reaction between titanium and nickel powders in high temperature molten salts. Results of the differential scanning calorimetry (DSC) confirmed the reverse martensitic transformation of the prepared TiNi powder in the TiNi/Ti2Ni composite powders. The backscatter electron images of the scanning microscopy (SEM) of the end-products before washing by distilled water showed that the synthesized TiNi/Ti2Ni composite particles were captured by the molten salts, which revealed the mechanism of the chemical reaction in molten salt.

Chemical mechanical polishing (CMP) is the effective technology which obtains high accuracy surface of hard disk substrate with nickel-phosphorus (Ni-P) coating. The slurry is significant factor in hard disk substrate CMP. Colloidal silica-based alkaline slurry was prepared based on negative pressure vortex method. The effects of slurry parameters such as abrasive concentration, organic alkali concentration and oxidant concentration on material removal rate and surface characteristics were investigated. The experimental result indicated that the abrasive concentration was 20wt%, the slurry pH value was 11.2, the oxidant concentration was 15ml/L, improved surface roughness and polishing efficiency of hard disk substrates, a smooth surface was obtained and micro scratches could hardly be observed.

The main failure modes of starter battery are discussed, the causes resulting in the premature failure of starter VRLA(valve-regulated lead-acid) battery are analyzed and corresponding countermeasures against failure of starter battery are presented. It proves to be of practical help.

The microstructure and tensile properties at room temperature of as-cast, solution-treated and aged samples of a Mg-5Sn-5Zn (wt%) alloy are investigated. The microstructure of the as-cast sample consists of -Mg primary, Mg-MgZn eutectic, divorced eutectic Mg2Sn and secondary precipitation Mg2Sn. After solution treatment, all the MgZn particles and the majority of Mg2Sn phases are dissolved into the matrix and the tensile strength and the elongation of the alloy increase obviously. During aging process many fine particles precipitate which result in the improvement of the yield strength.