Abstract: Many enterprises design their device with motion controller as one parts of whole equipment. On the Internet, if the engineer wants to do a remote technology support to a particular motion controller, the latter need to have an Internet IP address which can be accessed. Fixed (static) IP address with limited resources, the user must pay high cost. This paper presents VPN technique to remote technology support for Siemens SIMOTION motion controller. A detailed analysis of the application effect is shown. The result shows the feasibility of remote technology support to motion controller using VPN technology.
Abstract: Chemical mechanical polishing (CMP) has become an essential technique in advanced ULSI process. The mechanism of Ta CMP is discussed in this paper. According to the physical and chemical properties of Ta, the alkaline polishing slurry and proper process parameters for Ta CMP are prepared. The paper optimized four key parameters-abrasive concentration, organic alkali, oxidant and surfactant concentration, obtained the comprehensive optimized slurry used in evaluating the removal rate using Taguchi method. The results indicate that: abrasive concentration is 10%, the organic alkali concentration is 15ml/L, the oxidant concentration is 10ml/L and the surfactant concentration is 10ml/L, higher removal rate can be obtained.
Abstract: A fundamental study on the reaction between CO2 and mechanically activated metal powders has been conducted. In this research, the behavior and mechanism of CO2 reaction under various grinding conditions were investigated to fix and reduce CO2. The powder used was placed inside a grinding vessel, and was ground together with the SUJ2 balls in CO2 atmosphere. It was found that only the adsorption of CO2 gas on the ground samples was observed, whereas the decomposition of CO2 was not occurred. The CO2 adsorption increased proportionally with the increase in the grinding speed, weight of sample and number of SUJ2 balls. Furthermore, the CO2 adsorption increased with the decrease in the standard free energy of formation of each metal oxide. The morphology of the sample observed by SEM showed that the samples were not crushed into finer particles, but were only grazed on the sample’s surface. Therefore, it can be said that the CO2 can be adsorbed on the mechanically activated samples by using the centrifugal type ball mill, but in order to enhance the amount of CO2 adsorption, another type of machine with higher grinding intensity should be considered.
Abstract: Photocatalytic activities of simple mixture of TiO2 and NaX, and TiO2-NaX composite prepared by solid-state dispersion method were investigated. Methyl orange degradation rate increased sharply when TiO2 concentration was low and reached its maximum value at TiO2 concentration of 200 mg/l when using pure TiO2. After 120 min of irradiation, methyl orange degradation rate could reach 98.4%, which means nearly all of the dye degraded after two hours. The photocatalytic activity of TiO2 and NaX simple mixture increased with increasing amount of NaX up to 60.4% when NaX amount was 1.4 g/l. The composite TiO2-NaX prepared by grinding had lower activity at various NaX addition amount. The photocatalytic activity of composite TiO2-NaX prepared by solid-state dispersion was better than the composite before calcination. However, the maximum degradation rate was only 41.2%, which was still lower than pure TiO2.
Abstract: Using a first principles methodology, the adhesion of tungsten carbide and ferritic steel is investigated to estimate the mechanism of cutting process, which facilitates cutting performance enhancement and working lifetimes elongating. The Fe (100)/WC (100) interface is adopted based on minimum mismatched lattices with aiming to provide the suitable models to explore the structural and electronic properties at the interface. The W- and C-terminated surfaces are employed to clear the features of different surfaces of tungsten carbide. The comparisons of DOS, including bulk WC, Fe and their low index surfaces, show that surface-induced feature is generally presented on the surfaces. Bond character at the interface is studied with difference charge density and electron localization function (ELF), which allow us to predict the interfacial strength. Adhesion is due to strong covalent Fe-C bonds at the C-terminated interfaces, while W-terminated interface has no enough evidence to verify the presentation of covalent bonds. The calculated results support some advanced atomic studies on complex interface structures, especially improving the surface quality of metal products after machining process.
Abstract: Structural dynamics optimal design of key components is basis to reach optimal design of whole machine tool. The method of sensitivity analysis is applied to optimize the arrangement shapes and parameters of the strengthened bars of components. The BP neural networks model of the spindle system is established and corrected based on comparing with the experimental result, and the structure parameters of the spindle are optimized. These technologies will benefit to realize optimal design of whole NC internal grinder and guide dynamic optimal design of other machine tools.
Abstract: Ti-W composite coating was made by chemical conversion method on aluminum alloy. By orthogonal experiment, the optimal coating-forming conditions were the concentration ratio of TiOSO4 and Na2WO4 was 0.3 g/L:0.3 g/L、KMnO4 1.0 g/L、NaF 1.0 g/L、reaction temperature 40°C、reaction time 2min. The morphology of the coating was observed by scanning electron microscopy (SEM). Coating composition and the microcosmic phase structure were characterized using energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD) respectively. Electrochemical test was used to study the coatings corrosion resistance. The results indicated that the composite chemical conversion coating is a crystal structure material that composites with Al、Mn、W、Ti et al., its surface appears as a accumulation of fibroid spherical particles, the crystallinity of conversion coating is better than uncoated sample obviously. The corrosion potential of the coating is improved to -0.440V, they were both prove the corrosion resistance has improved.
Abstract: This present investigation describes the orientation and its influence factors of unidirectional C/C composites prepared by PAN-based carbon fiber and mesophase pitch (AR-MP) through hot pressure molding process. And the orientation of C/C composites was analyzed by POM and XRD. The experimental results indicated that the AR-MP dispersed in carbon fiber had a strong flow texture, showed a matrix preferentially oriented parallel to fiber surface. Under the pressure of 25MPa, the orientation of composites was better than under 50MPa. Moreover, the sample orientation varies in the two directions both perpendicular to the direction of carbon fiber. Better orientation was obtained in the testing direction which was perpendicular to the direction of carbon fiber and molding pressure.
Abstract: Instable plasticity, which is normally a consequence of interactions between diffusing solute atoms and dislocations, is observed in AZ91D magnesium at room temperature. Experimental measurements of different heat treatment of AZ91D magnesium were taken to investigate different influence on PLC effect by the presence and structural state of second phase in this study. Tensile specimens were tested at room temperature at a crosshead speed of 0.6 mm/min. The results indicate that some number of large,coherent precipitates prevents serrated flow by way of trapping vacancies, but small precipitates content do not supress it.
Abstract: There are many factors that affect the mechanical properties of laminated veneer lumber (LVL), such as the thickness of veneer, the compression ratio, the wood species and the density of LVL. In this paper, two different nondestructive testing (NDT) methods and the static shearing test were conducted on the birch (Betula platyphylla Suk.) LVL. The NDT methods included the flexural vibration method and surface wave propagation method. The effects of the compression ratio of LVL on the dynamic shear modulus and shear strength of LVL were investigated. The results showed that the dynamic shear modulus and shear strength of LVL were increased with the compression ratio of LVL increased, the increase tendency of NDT results and static shearing test results were consistent.