Applied Mechanics and Materials Vols. 496-500

Abstract: Conductive textiles can be used in diverse fields, such as antistatic materials, sensors, materials for electromagnetic shielding and biomedical. This study produces nonwoven fabrics with polylactic acid (PLA) and polyaniline (PAN) and the resulting PLA/PAN nonwoven fabrics are evaluated with electromagnetic shielding effectiveness (EMSE) and air permeability. Polylactic acid (PLA) and low melting point polylactic acid (LPLA) are made into nonwoven fabrics, which are then spray-coated with different amount of PAN solution to form PLA/PAN nonwoven fabrics. The fabrics are laminated with various numbers of layers, and then thermally pressed. The experiment results show that the PAN amount and lamination number are proportional to the EMSE of the PLA/PAN nonwoven fabrics.

Abstract: In the research, The electromagnetic interferences (EMI) have drastically increased and can disrupt and reduce the life time and the efficiency of devices. Therefore, the electromagnetic shielding problem is become the important issue. In the research, Ni wire and Cu wire (Floodlit Enterprise Co., Ltd.) were used to make the Ni conductive composite yarn and Cu conductive composite yarn via an electrical covering machine. And the Cu conductive composite yarn was fabricated to the woven fabrics with the plain weaving. The test results revealed that the EMSE of the W/K/W complex fabrics have stable EMSE than the W/W/W complex fabrics when the laminated at the same direction. The W/90W/W complex woven fabrics were shown the best EMSE of 46.25 dB, which the test frequency is 1800 MHz.

Abstract: Establishing Swanson constitutive model is discussed for composite solid propellant, which focused on the calculation of strain softening function and change strain rate correction function within the model. Prediction results of Swanson constitutive model are in good agreement degrees with the test of 24 groups uniaxial tensile data of composite solid propellant at different temperatures and extension rates. It proves the model is effective and available.

Abstract: The article focus on the metamorphic layer of punching die, punch matrix and die components in WEDM on the surface, the formation of metamorphic layer, the impact of metamorphic layers, line cutting the microscopic mechanism of the formation of cracks, and many were in-depth study and the corresponding preventive measures. These measures will speed up punching die design and manufacturing technology development. The die manufacturing technology here discussed can be the modern manufacturing technology research development direction.

Abstract: To improve mechanical properties and corrosion resistance, heat treatment is applied to the mechanical equipment (equipment and piping, etc.) during manufacture or installation. The nuclear class mechanical equipment with high reliability is required in nuclear power plant, but heat treatment is an important factor which affects reliability of mechanical equipment. To have a better view on issues of metal heat treatment, this paper will provide reference for subsequent heat treatment of mechanical equipment in nuclear power plant by analyzing and summarizing existing problems in heat treatment, especially during the reactor pressure vessel such heat treatment of large forgings, so as to avoid same problems.

Abstract: Mulberry raw silk is composed of sericin and fibroin and must be soaked before it is reeled. In this paper, the effect of soaking temperature and soaking time in clean water on mechanical properties and appearance of mulberry silk is studied. When soaking time is 40 min and soaking temperature is 55 °C, the resulting silk can satisfied with further operation.

Abstract: As to three kinds of continuous gas lift design methods commonly used using surface casing pressure control all have several disadvantages when the pressure drop between the valves is small, and they have some deficiency when gas injection pressure is relatively inadequate on ground or want to play the affection of the gas injection pressure on ground as much as possible, therefore, the applied study is made in this regard. First, the precise calculation method of the top valve depth under different conditions was achieved based on the principle of U type tube, then an improved variable pressure drop design method was derived based on the basic principle of gas lift unloading and by using another set of gas injection pressure system on ground independently for designing the valve depth. The obvious advantages of the improved method were found by comparing the available maximum of the gas injection depth and the production rate of the existing methods and the improved method in the same condition of gas injection on ground and on the basis of ensuring the safety design principle.

Abstract: A grinding method with CNC machine for face gears is studied. Firstly, the single indexing generating grinding method of face gear is introduced. Then, a grinding experiment of face-gear is performed on a CNC grinding machine with five degrees of freedom, and the tooth deviation is measured on gear measuring center. The tooth surface error is obviously decreased after grinding, and the precision of face gear tooth surface is improved significantly. Finally, a rolling test is performed which indicates that the contact path on face gear before grinding shows discontinuous because the surface deviation is over big. The contact path gets better after grinding.

Abstract: In this paper, combining with the experimental data in the reference, the purpose is to research effect of three different aperture ratios (α=6%, α=9%, α=12%) of distributor on the fluidization quality of vibrated fluidized bed (VFB). Euler-Euler model in Fluent is used to simulate the flow state. User-defined functions are used to define vibration model, and the distributor is simplified based on the porous media model. The results show that the introduction of the distributor can improve uniformity and quality of the fluidization. The aperture ratio of distributor has little influence on material distribution, however, the uniformity of the fluidization is improved with the decrease of the aperture ratio.

Abstract: In this study, the main aims were to iron-increasing and silicon-reduction of the iron concentrate by using centrifuge separating technology. Experimental studies were carried out on high-silica ferromagnetic iron concentrate in Dahongshan samples, which contain 50% of iron and 15% silica. Through the experiment, it chooses SLon1600 to iron-increasing and silicon-reduction of the iron concentrate. The optimum condition is pulp density of 20%~25%, feed speed of 1.99t/h, rinse water of 6.4t/h and flushing water of 10.22t/h. The iron concentrate which the grade of Fe is 62.36% and the recovery of 80.47% is obtained and the grade of silica reduce from 14.48% to 5.4%. High-quality iron concentrate is obtained, which has a better effect.