Advanced Materials Research Vols. 148-149

Abstract: Wood was treated by double-diffusion method to form the precipitates of metaborates in wood. Their leachability in running water was evaluated. The precipitates of these metaborates in the wood proved to be insoluble or hardly soluble in water by the leaching test, and the best leachability for that by double-diffusion treatment with Pb2+ solution. Their flame retardancy was evaluated by limiting oxygen index (LOI) and cone calorimeter. The resultant data showed that their flame retardancy and smoke suspension were increased by the double-diffusion treatment and the best for that by the treatment with Zn2+ solution.

Abstract: Experiments for a new type of electric discharge machining (EDM) were conducted with the water film dielectric formed by tap water and compressed air. An energy factor E is introduced and employed to estimate unit-area effective power input. The experiments show that the flushing conditions with lower air jet pressure can get lower relative tool wear and higher material removal rate (MRR). Higher discharge current and higher energy factor E obtain the higher MRR in air-aided water EDM with positive polarity tool.

Abstract: Ionitrriding and plasma arc surface quenching are seprately used to harden screw surface for settling the wearing problem of bulking machine extruding screw during the feed production process in the paper.The results indicate that surface hardness is incresed 1～2times and the depth of harden layer is about 0.15～0.3 millimeter by ionitrding,but plasma arc surface quenching can improve the surface hardness of screw 2～3times, and the depth of harden layer is about 0.2～0.45 millimeter. Metallurgical structure of harden layer is also analysed and discussed.

Abstract: Loads calculation process for pitch bearing of wind turbine was presented. The aerodynamic of the rotor was analyzed by using momentum theory and blade element theory firstly; then the aerodynamic loads, the gravitational loads and the centrifugal loads of the pitch bearing were calculated along each axis of the bearing coordinate system; thirdly, all the loads of each direction of the pitch bearing load were composed into three loads, they are radial, axial and tilting moment loads. A calculation example was given at last.

Abstract: A new type dynamic vibration absorber, which consists of steel layer and variable cross section rubber layer fitted to plate by bolt through L-shape connection, is introduced firstly and applied to control vibration of plates at multi mode frequencies in this paper. The aim of the present paper is to study the energy absorbing ability of the new type dynamic vibration absorber and apply optimization method to obtain parameters of absorber which is excellent in absorbing energy. The coupling model of composite beam and plate is established by power flow method and energy of plate attenuated by absorber is analyzed. To improve energy dissipated by absorber, the particle swarm method is used to optimize parameters of absorber to minimize vibration energy of the plate. An experiment is executed to certificate the energy mitigated by absorber to validate analytical modeling method. The test data are consistent with the analytical results, demonstrating that the new type dynamic vibration absorber can suppress the vibration energy at every mode of plate and achieve a goal of multi-mode control.

Abstract: This paper took the application of nanotechnology for green manufacturing as a point of departure, discussed the important roles of nanotechnology in green design, green material, green process, green package and green treatment as follows: nanotechnology reflected the use of natural resources embodying the harmonious coexistence between human being and nature which happened to coincide with the basic idea of green design; with the further integration of nanotechnology and environmental protection, nanotechnology led the development of green material into a new level; the introduction of nanotechnology gave new ideas to the development of green process; green package based on nanotechnology could meet the special functional requirements of package with outstanding green efficacy; the development of nanotechnology enhanced the existing level of green treatment technology, many existing problems could be resolved. And finally it was pointed out that the green manufacturing technology would make further development under the push of nanotechnology.

Abstract: The relationship between the morphology and protective action of hot-dip aluminizing coatings on Q235 steel have been investigated by SEM, EDS and EIS in 3.5 wt% NaCl aqueous solution. The results indicated that the anti-corrosion performance of the hot-dip aluminizing coatings using steel substrate rinsed by the distilled water at 25 oC was higher than that at 80 oC. The evolution of localized corrosion from pitting to exfoliation corrosion has been found on the aluminum coating surface during immersion, and corresponding equivalent circuit models were proposed to fit the EIS data in the initiation and propagation stages of corrosion process.

Abstract: In this paper, the parameters which influence the pyrolysis of Printed Circuit Board (PCB) are studied with Taguchi experimental method. Matrix experiments used L9 (34) orthogonal allays are employed to evaluate the effects of parameters in recycling of PCB by pyrolysis approach. A statistical analysis of Extreme difference and signal-to-noise ratio is followed performing an analysis of variance (ANOVA), the result shows that the critical factor for the loss of weight is final temperature and temperature change rate. The contribution of final temperature is about 97.16% to the loss of weight; while the influence of other parameters is very small.

Abstract: A multi-component polymer-coated molybdenum powder was chosen for selective laser sintering (SLS). A novel preparing method of polymer-coated molybdenum powder was presented. The effect of the process parameters on the part’s characteristics is investigated. Based on our study for dynamic laser sintering process of polymer-coated molybdenum powder, its laser sintering mechanism was reported as follows: at the early stage of laser sintering, the viscous flow is the major mechanism; during the laser sintering, the melting/solidification is the major mechanism. Furthermore, a model corresponding to the mechanism was discussed schematically, which could be used to explain the material migrating mode during laser sintering process.

Abstract: This paper establishes a combination forecasting model based on Radia Basis Function Neural Network (RBFNN). It puts forward a seeking optimum parameters method by searching optimal solution for two-dimensional space (goal, spread) in a certain range, and realizes the combination forecasting of logistics demand, and improves the stability of network and the precision of prediction in RBFNN. An instance is presented to realize the model by MATLAB. The results showed that a good fitting precision and a high forecasting precision are reached in the application of the logistics demand forecasting by the designed forecasting model.