Applied Mechanics and Materials Vols. 380-384

Abstract: The property of the soft magnetic composite (SMC) material is introduced. Take the traditional material used for electric machine, i.e. the silicon steel lamination, as the reference, this paper summarizes the application advantages of SMC in the typical electric machine, such as tubular permanent-magnet liner machine, high-speed permanent-magnet machine, claw-pole machine, axial flux permanent-magnet machine and radial flux permanent-magnet machine. SMC material has much applied potential in the field of electric machine.

Abstract: The structure and thermal parameters of biomedical used Ni₂₀Pd₈₀ alloy were studied using X-ray diffraction (XRD) technique. The diffraction experiments performed in the temperature range of 308-1100 K revealed that the alloy forms a face centered cubic (fcc) A1-type structure. The temperature dependence of the lattice parameters was investigated using the Bragg line displacement method shows that the lattice parameter increases with the increase of temperature. The mean linear thermal expansion (MLTE (%)), coefficient of thermal expansion (CTE) α, the characteristic Debye temperature (Θ_D) and mean square amplitudes of vibration were determined from the XRD data. The value of Debye temperature was found to be 253 K. It was found that temperature factor was independent of the static displacements.

Abstract: Several reaction pathways on the potential energy surface (PES) for the radical-radical reaction of CH₃O₂ + CN have been investigated theoretically at the CCSD (T)//B3LYP/6-311++G (3df, 3pd) level. The calculations show that the CH₃OOCN and CH₃OONC are the most stable intermediates. The direct dissociation of CH₃OOCN (im2) leading to CH₃O + NCO is predominant on the energy surface, and the CH₂O + HNCO are expected to be secondary products.

Abstract: The process of laser additive manufacturing consists of depositing successive layers of molten metal powder to create a near-net shape. A high-power laser is used to melt incoming metal powder, which forms a molten pool on the surface. As the latter moves beneath the laser, this newly created molten pool solidifies. By properly controlling the trajectory of deposition tracks, one can create a diverse range of shapes with varying complexities. In nature, the laser additive manufacturing technology is a continuous multilayer laser cladding process under the control of computer. The microstructure morphology of cladding layer is essential for the performance of as-deposited metal parts, so the cladding process was studied through related experiment. Based on the solidification theory, the microstructure morphology and the evolution rule were comprehensively analyzed. The results indicate that the temperature gradient and the solidification rate are the primary factor determining the microstructure morphology of cladding layer.

Abstract: The laser additive manufacturing technology is a laser assisted direct metal manufacturing process. This process offers the ability to make a metal component directly from CAD drawings. The manufacturing equipment consists of some components. Among them, the laser transmission component plays an important role in the whole fabricating process. It provides the energy source to melt the metal powder, so it is necessary to develop the laser transmission technology. This technology is achieved primarily by laser generator system and optical path transmission system. The related structure design and function implementation prove that the laser transmission technology can generate desirable laser power at precise assigned position, and complete the manufacturing process with flying colors.

Abstract: Due to its excellent performance, the rigid polyurethane has been widely used in the building construction nowdays. This paper introduces what is rigid polyurethane foam and its main chemical constituents of the composition and principle, describes the main properties of rigid polyurethane foams and its present application status and development prospects, to provide reference for further development and research of the rigid polyurethane foam in the days to come.

Abstract: TiB2-TiC multiphase ceramics were prepared through altering the molar ratio of Mg and C and leached with suitable acid by the combustion synthesis reaction of Mg, C, TiO2 and B2O3. The samples were investigated by XRD and SEM, and the results showed the diameter of the TiB2 was 1.5μm and the shape of the TiC was irregular spherical particles. The diameter and the proportion of the TiB2 were increased with the increase of Mg powder. The formation mechanism of TiB2 has been studied. The optimized proportioning of the molar ratio of Mg and C was 3:2.

Abstract: Laser Metal Deposition Shaping (LMDS) is an emerging manufacturing technique that ensures significant reduction of process time between initial design and final components. The fabrication of fully dense parts with appropriate properties using the LMDS process requires an in-depth understanding of the entire thermal behavior of the process. In this paper, the thermal behavior during LMDS was studied, both numerically and experimentally. Temperature distribution and gradient in the fabricated part were obtained by finite element method (FEM) simulation. The numerical results are in good agreement with the experimental observations. The numerical method contributes to the comprehension and control of the thermal behavior, and may be used to optimize process parameters and predict the thermal response of LMDS fabricated components.

Abstract: Established a unified equation of conical surface cutting line, analyzed the main cutting line critical characteristics, studies the section curve of plane problems, discussion plane curve property, continuous planar interception solution of two types of components are presented.

Abstract: Wind energy is an inexhaustible, an inexhaustible source of renewable and clean energy. Present due to the energy crisis and environmental protection and other issues, the use of wind more and more world attention. The wind turbine is the best form of wind energy conversion. Wind turbine wind turbine blades to capture wind energy is the core component of the blade in a natural environment to run directly in contact with air, with seagulls wings generate lift conditions are similar, so the gull wings airfoil and excellent conformation, with wind turbine blade design designed by combining the bionic blades. Through numerical simulation analysis found bionic blade aerodynamic performance than the standard blade aerodynamic performance has improved.