Abstract: An introduced article deals with the possibility of re-use of waste materials in production. The observed properties are the tensile properties of newly created material, namely yield stress, stress at break. Changes in strength characteristics and suitability of replacing the pure, primary material with the secondary, waste plastics were determined by material tests. The report gives a cross-section in methodology of tests performing, results processing and implementation into practice.
Abstract: The objective of this research is to study the mechanical properties of recycled wood particles epoxy matrix composites through the manipulation of composites wood particles size and weight fraction for tensile tests with different strain rate. Wood saw dust has been collected from a saw mill, dried and sieved into 300 and 600 μm. Unsieved wood particles were also used in this study. Each of the categories of wood particles was mixed into Epoxy resin with weight percentage of 20% and 40% of total composites to produce dumbbell-shaped tensile test specimens. Result shows that there is an optimum wood particles size where the tensile properties are at the highest before the properties start to decrease with increasing particles size, except for 20% wt. wood particles whereby the Young’s modulus is the highest with mix (largest) wood particles. With increasing wood particles weight percentage, tensile strength decreased while young’s modulus increased. A wood plastic composite (WEC) was shown to be strain rate sensitive whereby tensile properties increased with increasing strain rate. Our study proves that WPC can be very advantageous due to its higher average tensile strength and also high young’s modulus compared to commonly used materials in the industries.
Abstract: Roughness is an important perceptual characteristic of material surfaces. This work investigated a derived model for evaluating surface roughness in accordance with human visual perception. This was accomplished with the help of extensive psychophysical experiments. Surface textures resembling natural materials were generated with different roughness. Subjects rated the surface textures on 5-point Likert scales based on visual perception of surface roughness. We trained a general model for mapping features of surface images to perceptual scales of roughness. It can be observed that the roughness obtained in this way is in good agreement with that perceived by human. Thus, given a material surface, roughness can be estimated accurately.
Abstract: This paper made a study of preparation of the electrorheological materials applied to ER clutch. Several experiments were made to research the influence of the solvent, deionized water, dropping rate, and the inhibitor on the gel time,and different gel time under different experimental conditions were obtained. The experimental results provided a reference of experimental conditions for preparing electrorheological materials applied to ER clutch. The conclusions can be good used to analyze the effect of the gel time on electrorheological fluid nature for ER clutch, and then improve the ER clutch performance.
Abstract: Quantities Mg-12Gd-5Y-3Zn-0.6Zr magnesium alloy billets were compressed with true strain 0.7 on hot process simulator at 350,400,450,480°C under strain rates of 0.001, 0.01, 0.1 and 0.5s-1. A constitutive model with a few parameters is used to characterize the dynamic recrystallization strain softening of Mg-12Gd-5Y-3Zn-0.6Zr alloy, which comprehensively reflect the effects of the deformation temperature, strain and strain rate on flow stress.
Abstract: The corrosion behavior of hydrostatic extruded tube AZ80 magnesium alloy was investigated by polarization curves and electrochemical impedance spectroscopy (EIS) in simulated atmosphere. The results indicated that, the corrosion resistance of the hydrostatic extruded AZ80 magnesium alloy with uneven deformed grains and increased sub-grains were obviously weakened, with larger corrosion current density in the polarization curves and lower corrosion resistances in the electrochemical impedance spectroscopy plots. This was mainly because of the hydrostatic extrusion which made AZ80 magnesium alloy within large numbers of dislocation tangles. So the residual stress increased the electrochemical activity of magnesium alloy which reduced the corrosion resistance of magnesium alloys.
Abstract: Using FGD gypsum as raw material, calcium sulfate whisker was prepared by hydrothermal synthesis method. Through testing the aspect ratio of calcium sulfate whisker, the effect of reaction temperature, reaction time, desulfurization gypsum slurry concentration and pH value on the growth of calcium sulfate whisker were deeply researched. The optimum conditions for the preparation were that the reaction temperature was 150 °C, reaction time was 270min, the slurry concentration was 10% and the slurry pH value was 6.
Abstract: This paper summarize the transparent conductive oxide (TCO) market application of aluminum doped most widely used in the film Zinc Oxide AZO and ITO thin films and the development trend is prospected. Reports the photoelectric properties of ITO films requirements, prepared on flexible substrate ZnO films on the substrates, preparation technology and development, summarizes the latest research achievements in this field and the present problems, which describes the next step of work in the domain.
Abstract: TiO2 nanotube arrays (TNAs) fabricated by anodization were quenched to obtain high-quality samples for the application of such electrodes in dye-sensitized solar cells (DSSC). The morphology, crystallization structure and photoelectrochemical properties of the samples were studied. The results showed that the quenched nanotubes assembled together into bundles but every single one maintained tubelike shape. In transient photocurrent response of electrode, photocurrent increased with the increasing of bias potential and photoelectrochemical properties of quenched electrodes were better than the unquenched, displaying obvious characterization of slow current response. When applied in DSSC, the sample quenched at-100 °C in ethanol displayed the best performance with Jsc = 4.186 mA/cm2, Voc = 0.781 V, FF = 0.48, η = 1.569 %.
Abstract: This paper studies changes in the relationship between magnetic properties of La5/8Ca3/8Mn1-xCoxO3 (x≤0.3) system and temperature and magnetic field. By the lattice structure of the sample when x=0.3 varies with temperature analysis that, related changes of lattice structure also occurred in the magnetic transition region. The difference of lattice parameter is increased, orthogonal O' phase substitute orthogonal O. We speculate that spin-state transitions may be appear in this interval. At low temperature of x=0.3 sample, the behavior of AFM sample should coexist with the CG, eg itinerant electron reduce, resistance increase and drastically reduce conductivity.