Applied Mechanics and Materials Vols. 488-489

Abstract: Solar energy is the inexhaustible,enewable Energy. The solar cell is the solar light energy into electricity. The unique advantages of solar cell. Potential, more than wind, hydro, geothermal energy, nuclear energy and other resources, is expected to become the main pillar of power supply in the future. This paper studies that the main parameters of monocrystalline crystal silicon solar battery: the junction depth and superficial concentrations influence on electrical characteristics of monocrystalline silicon solar battery. The result shows that for maximum efficiency, it is bound to get the largest possible open circuit voltage, short circuit current and fill factor of the product, therefore, it is necessary to control these two parameters, the junction depth and doping parameters. If the junction depth is constant, with the increased superficial doping concentration of monocrystalline silicon solar battery, the photoelectric conversion efficiency of the battery increases slowly at first and then rapidly decreases, and the deeper the junction depth is, the more obvious trend of the photoelectric conversion efficiency is.

Abstract: The influence of sputtering power, N₂ flow rate, ion current and substrate temperature on the monolayer TiN films deposited by ion beam assisted magnetron sputtering and the effect of the on-off ratio and deposition period on the multilayered Ti/TiN films was studied. It was found that the key factors affecting surface defects of monolayer TiN films are sputtering power and N₂ flow rate while ion current is the most significant factor affecting the hardness of monolayer TiN films. The surface defects can be greatly inhibited by pulsed gas feeding. The adhesion and hardness of the multilayered Ti/TiN films is improved with increasing on-off ratio or decreasing deposition period; the on-off ratio has a negligible effect on the surface defects of the multilayered Ti/TiN films while the surface defects of the multilayered Ti/TiN films become more obvious at a long deposition period.

Abstract: The influence of chemical vapor deposition process parameters including carrier gas composition, deposition temperature, and content of reactants on the structure of graded SiC-C coating is discussed on the basis of thermodynamic calculation in this paper. The addition of enough hydrogen into carrier gas is necessary for the fabrication graded SiC-C coating. The increase of deposition temperature benefits the control of composition in graded coating but the concentration of free Si and free C becomes high at a too high deposition temperature. A high concentration of reactants is preferred while more defects are apt to exist in coatings if the concentration of reactants is too high. The optimum CVD process parameters for graded SiC-C coating are: gradually changing the molar ratio of SiCl₄ and CH₄ from 0 to 1 when the concentration of CH₄ in hydrogen is 1-2 vol%, and the deposition temperature is 1200-1500 °C.

Abstract: Superalloy CMSX-6 have a high concentration of high-melting point additions, which causes an increase of the turbine blades' working temperature. It has potential application particularly in turbine blades of aircraft jet engines. The superalloy CMSX-6 Blades casting were obtained after pouring the shell mould in the work, and effects of pouring temperature on the solidification directional microstructure of casting were investigated using scanning electron microscopy (SEM) techniques. The results showed that with the increase of pouring temperature, the primary dendrite arm spacing of CMSX-6 superalloy blades decreased, the size of γ phase in the dendrite trunk and in the inter-dendrite decreased slightly, and the size of the γ-γ eutectic did not change largely, the volume fraction of γ-γ eutectic increased slightly, the main defects such as pores and shrinkage cavity decreased, its size became smaller.

Abstract: Development process of Hot-dip galvanizing technology and characteristics of different production methods were reviewed in this paper. Presently, the UEC method was utilized widely because of its advantages like high output, high quality, energy saving, lower consumption and low products cost. To improved the corrosion resistance of the coating and declining the cost of hot-dip galvanizing, hot-dip galvanizing alloyed coating has been developed. Although the general hot-dip galvanizing has been developed rapidly in China, we should make great efforts to research deeply and improve the hot-dip galvanizing technology, especilly in the areas such as zinc alloy plating and the corresponding hot-dip galvanizing technology.

Abstract: This paper investigates the growth behavior of fatigue cracks initiated at corrosion pits in laboratory coupons of LC9 aluminum alloy subjected to a transport aircraft loading spectrum. Corrosion pits were introduced by exposing the coupons to EXCO solution for a variety of periods to produce corrosion damage varying from mild to severe. In general, the presence of corrosion damage reduced the fatigue lives of components to a severe extent. It was found that the depth of the corrosion pit was a suitable parameter for characterizing the corrosion damage and for predicting the fatigue life of the coupons using commercial fatigue crack growth software

Abstract: Objective: To optimize the ultrasonic degradation of aniline wastewater process parameters. Methods: ultrasonic power, ultrasonic time, ultrasonic temperature, pH value, etc. 4 orthogonal factors and determine the optimum process conditions. Results: In the ultrasonic power 320W, ultrasonic time was 60min, ultrasonic temperature is 30 °C, pH value of 4 under the action of ultrasound sonication best, under optimum conditions, aniline degradation rate of 90.08%, and the various factors the impact of the size order of ultrasonic temperature> ultrasonic time> ultrasonic power> solution pH. Conclusion: Ultrasonic degradation of organic matter, is easy to operate, efficient, non-polluting or less polluting characteristics, is a better degradation of aniline wastewater new technology.

Abstract: Combining phase transformation with deformation effectively, a new preparation process of ultra-fine grain medium-carbon steel using martensitic steel was developed. In this research, quenched steel was heated to 500~600 °C quickly, and tempered for an appropriate time to retain a certain degree of supersaturation. Then quick warm deformation was implemented. By the action of twinning, dislocation decomposition, recrystallization, etc., which realizes dislocation motion on slip planes to form dislocation forests or cross-slip, supersaturated ferrites are refined quickly. Strain-induced cementite particles precipitate dispersively in grain boundaries or sub-grain boundaries, and uniform and stable structures are obtained.

Abstract: The unfolding is the first step for the manufacturing of the sheet-metal part, which plays a major role for the accuracy and quality of the final product. Unfortunately, the inefficiency of the traditional drawing-based method made the process boring and sometime confusing. The CAD method made benefit for the designer. By means of the 3D modeling kernel and the mathematic model of unfolding process, the automatic design system of sheet-metal part was developed, in which the models are parametric and in 3D environment.

Abstract: This article studies the effects of heat source shape parameter and welding speed on the evolution of welding temperature field for Q345 plan carbon steel. The heat input and heat source parameters as well as the welding speed are defined by applying DFLUX subroutine in ABAQUS to simulate the transient welding temperature. The effects of heat resource shape parameters and heat input as well as the welding speed on welding temperature field are investigated by means of finite element analysis. It has been found that heat source parameters and welding speed show strong influence on temperature distribution in FZ (fusion zone) and HAZ (heat-affected zone). Meanwhile, it shows a roughly linear relationship between the changes of heat input and the highest temperature.