Advanced Materials Research Vols. 197-198

Abstract: This paper presents a self-adaptive fan clutch for automotive application using MR fluid and SMA. Based on Bingham model, the equation of transmission torque developed by the MR fluid for fan clutch is derived. A SMA spring actuator is designed to control the angular velocity of the fan clutch. The characteristic of output angular velocity is studied in detail. The results indicate that, the change of temperatures has a tremendous influence on the output angular velocity characteristic of the fan clutch, and output angular velocity of the fan clutch can meets the demand of engine cooling fan satisfactorily.

Abstract: Copper nitride films were prepared by reactive magnetron sputtering on glass sheets at different deposition conditions. The surface morphology of the films was evaluated by a scanning electron microscope (SEM). The SEM images demonstrate that the films have a compact structure. The structure of the films was characterized by X-ray diffraction (XRD). We focused on the influence of preparation parameters on the adhesion and electrical properties of the films. The metallurgical microscope results indicate that the adhesion of the films enhances with increasing deposition power. The current-voltage (I-V) measurement results show that the resistivity of the films increases with the increasing lattice constants.

Abstract: N doped ZnO thin films were prepared by magnetron sputtering. The effect of bias voltage, N₂ flow and introducing of Al on the behavior of N doping into ZnO films were investigated. The results show that there is little help for N doping into the ZnO films by just adjusting N flow rate because the magnetron sputtering method has a relative weak ability on dissociating the N₂. The data of co-doping of Al and N into ZnO films revealed that co-doping is an effective way to advance the N doping into ZnO films. The coordination of Al doping and bias voltage could help the N doping effectively.

Abstract: In this paper, combined with the supercell technique, the plane wave expansion method is used to calculate the band structures of the two-dimensional phononic crystals with line defects and the random disorders in either radius or location of the scatterers. Phononic systems with plumbum scatterers embedded in an epoxy matrix are calculated in detail. The influences of the random disorder on the band structures of anti-plane waveguiding modes will be discussed. The displacement distributions are calculated to show the wave localization phenomenon. Propagation of the guided wave in the phononic crystals with different disordered degree is studied. The analysis is relevant to the assessment of the influences of manufacture errors on wave behaviors in waveguiding phononic crystals as well as the possible control of wave propagation by intentionally introducing disorders into the systems.

Abstract: 4-dimethyla-mino-N-methyl 4-stilbazolium tosylate（DAST） crystals were prepared by the slope nucleation method (SNM). The structural and optical properties of the grown crystals were studied by employing powder XRD and FIIR. The surface morphology of DAST crystals was observed by scanning electron microscope (SEM). The Vickers hardness studies were carried out on (001) and (110) faces of grown DAST crystal. The values of Meyer’s index number n and hardness were calculated from H_v. The results showed that the DAST crystals belong to the soft material category.

Abstract: Tetra-needle-like zinc oxide whiskers (T-ZnOW) were coated with Zn and stabilized with Al₂O₃ consequently. Coating conditions for preparation of low resistivity T-ZnOW were investigated. The Zn-coated T-ZnOW was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrical resistance measurement. The SEM and XRD results indicated that the tetra-needle-like structure of ZnO whiskers could be well maintained after coating with Zn and stabilizing with Al₂O₃. Experiment results showed that the resistivity of T-ZnOW was affected significantly by the annealing temperature, annealing time, coating amount of Zn and original content of Al³⁺. Al³⁺ ions played an important role in stabilizing the resistivity of Zn-coated T-ZnOW. The resistivity of T-ZnOW decreased considerably from 10⁸ to 10¹ Ω•cm when the Zn-coated amount and Al³⁺ original content were 10.0 wt.% and 2.0 at.%, respectively.Introduction.

Abstract: A hybrid containing two organic components of n-butylamine and methylamine based on CuBr₂ was synthesized by reaction in solution. The influence of solvent and the feed ratio on the structure of the product were investigated. The structure and the thermostability of the hybrid were characterized using X-ray diffraction, chemical elemental analysis, infrared spectroscopy and thermogravimetric analysis. Comparing with the hybrid based on CuBr₂ containing only one organic component of n-butylamine, the hybrid containing two organic component s of n-butylamine and methylamine based on CuBr₂ also have layered perovskite structure and it can be synthesized with appropriate reaction conditions. The hybrid can illuminate blue light under the excitation of ultraviolet light.

Abstract: In this paper, effect of pre-deformation and ageing on compressive behavior of Ti-58.25wt%Ni was investigated at room temperature. Through range analysis of three factors and three levels on transformation temperature measured by DSC, ageing at 673K enhanced phase transformation temperature obviously, the As temperature could reach 308.02K. Transformations of B2-B19’ and B2-R-B19’ appeared after the treatments. Saw tooth shape phenomenon on the loading curves indicating the typical martensitic transformation was also observed. Dynamic balance due to compatible action among various phase under increased load kept the slope of the loading curves constantly. Pre-deformation by 0.2% resulted in higher compressibility (4.9%), and ageing at 523K caused better recovery (95.4%).

Abstract: Effect of organic bentonite on rheological behavior of paper coating was studied. Organic bentonite was prepared by treating sodium bentonite with dimethyl diallyl ammonium chloride (DADMAC) at the following conditions: DADMAC 20%, reaction time 3h, reaction temperature 80°C and pH 9. The results showed that shear stress and voscosity of coating enhance with increasing the amount of organic bentonite. In this testing, all of flow curves fitted Cross model very much, and rheologiclal properties showed the pseudoplastic fluid, characterized as obvious shear thinning .The bentonite modified with DADMAC could promote the rheological behavior of coating.

Abstract: With soaking treatment, cerium and KH560 silane compound mixture conversion coating are formulated. Various means of analysis such as SEM, EDS, IR, Tafel and EIS were adopted to carry out analysis of surface pattern, element constitution and electrochemical corrosion for mixture conversion coatings of different immersion time. The result shows: When the mixture conversion coating of cerium and silane are formed, the cerium conversion coating takes the priority in generation. Silane conversion coating is mainly absorbed to the cracks of cerium coating, once some exposed base are found at the minor cracks of the silane coating, as a result, definitely cerium coating is generated to make up the exposed base. Therefore, the corrosion resistant capabilities of the mixture conversion coating are higher than pure cerium conversion coating and silane conversion coating.