Advanced Materials Research Vols. 490-495

Abstract: In this paper, we present the modeling and kinematics simulation of fine-adjustment system for segment erector of tunnel boring machine (TBM), which is performed in the virtual prototype platform. The 3D virtual assembling model of fine-adjustment system is built with Pro/E software according to its design parameters such as structure and size. After the interference inspection, the model is imported into ADAMS through the interface module of Mech/Pro. The model is simplified and optimized reasonably and various constraints are applied under variety working conditions. The results of simulation show that the design has three degrees of freedom movement capacity which meets the design requirements. At the same time the kinematics characteristics of each part along three different directions are obtained and they will provide some references for the further optimal design.

Abstract: We have investigated the properties of the ultra-thin layer all-fluorescent nondoped white organic light emitting diodes based on blue-emitting binaphthalene derivative (BN) and ultra-thin green and red emitters. By optimizing the thickness of BN, we found that the device exhibited a high color rendering index (CRI) of 84 and high chromatic-stability with the Commission International de L’Eclairage coordinates shifting from (0.26, 0.32) to (0.27, 0.33) as the luminance increased from 40 to 10645 cd/m2. In addition, we also achieved a low current efficiency roll-off, which current efficiency only reduced from 3.77 cd/A to 3.36 cd/A when the current density increased from 13 mA/cm2 to 104 mA/cm2. High CRI and low efficiency roll-off are of significance for the applications of organic light-emitting diodes in display and lighting.

Abstract: To study the PCO of high-salinity organic wastewater, nano-sized TiO2 was used for PCO of MB in solutions with different pH values and high concentrations of Na2SO4 or NaCl. The rates of PCO were monitored by total organic carbon (TOC) measurement. The results showed that the degradation rates increased with increasing pH and decreased as the concentration of Na2SO4 or NaCl increased. The difference of degradation rates in Na2SO4 or NaCl aqueous solutions increased as the ion concentration increased. In the orthogonal experiments, the rates decreased remarkably under certain ratios of the ions concentration. The mechanisms were explored in some detail.

Abstract: Al-Cu-Fe with an atomic ratio of 70:20:10 was selected for preparing the quasicrystalline coating by low power plasma spraying. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used for analyzing the phase component and microstructure of the quasicrystalline coating. It was found that the best quality of quasicrystalline coating was obtained under a current of 400A and a voltage of 40V. XRD results show that, using these parameters, a relatively higher content of quasicrystalline phase can be acquired in the coating. SEM results show that the sprayed coating has a low level of porosity.

Abstract: The purpose and method of this paper is to comparatively analyze several commonly-used cushion packaging materials, obtain their shock absorption characteristic curves, and by doing such, provide reference information for cushion packaging design and research. With the static test, dynamic compression test and vibration transfer test carried out, the cushion coefficient ~ static stress curve, maximal acceleration ~ static stress curve and vibration transfer rate ~ frequency curve are gained. A final conclusion is educed that in practical design routine, rational choice of cushion packaging materials, scientific design of packaging structure and validation of anti-vibration capability are relative to those three curves.

Abstract: Composite sandwich structures have been used more and more widely in the underwater structures, therefore deformation problems under deep-water hydrostatic pressure can not be ignored. For the deformation properties of composite sandwich structures under deep-water hydrostatic pressure, the paper carried out theoretical and test research. First, the paper analyzed the surface deformation features as well as the law of the element’s cross-sectional dimension, the core thickness and elastic modulus to the surface deformation by establishing theoretical analysis model; The results show that the deformation area can be divided into central area and boundary area, and the boundary effect is an important factor affecting the deformation, the core parameters can affect the reach of boundary effect. Second, the paper carried out hydrostatic test of composite sandwich structural element model, and then verified the theoretical analysis model’s rationality and accuracy by comparing the test results and theoretical results.

Abstract: To select reasonable cutting parameters, improve the processing surface quality, and extend the tool life, this paper uses four solid carbide end milling tools to process TC4 titanium alloy, and analyses the influence of the difference cutting parameters and the geometric angles to chip shape. The experiment results indicate that the degree of serrated chip shape is increased by increasing the feed rate under the condition of certain spindle speed. But the degree of serrated chip shape may be decreased by the adoption of small axial and radial depth, or bigger rake angle and smaller helix angle. Select larger rake angle, cutting edge is sharp, the metal deformation of cutting layer is small, which can reduce the friction force when chip flowing through the tool rake face, so that the cutting force and cutting temperature decreases accordingly.The greater the helix angle is, the worse the chip removal conditions is, and the degree of serrated chip becomes larger, the blade is more sharp, easily crack, and the tool life decreases. So relatively small helix angle is better. The choice of angles is interrelated with each other, the selection of some angle separately cannot get the desired reasonable value.

Abstract: The aim of this article was to propose a macroscopic damage model, which describes the nonlinear behavior observed on woven C/SiC ceramic matrix composites. The model was built within a thermodynamic framework with internal variables. The anisotropic damage evolution processes of the material were described by nonlinear damage isotropic and kinematic hardening functions in this model. The anisotropic damage and damage coupling were considered with a damage yield function including anisotropic coefficients. Using the principle of energy equivalence, the damage variables were defined by the unloading modulus and initial modulus. The damage variable and the irrecoverable strain induced by micro-crack propagation were deduced by thermodynamics. The constants of constitutive model were identified and the damage evolution processes under tensile and shear loading. Uniaxial tension and shear tests had been used to valid the constitutive model to C/SiC composites.

Abstract: The paper introduces the work process and control requirements of precast concrete pipe pile perfusion. Th design is based on the S7-200PLC and AE80THTD touch screen control system. It elaborates the hardware components of control system, I / O configuration, software workflow and control chart. The practical operation shows that the control system is convenient to manufacture, install and commission, easy to operate, and it is stable and reliable.