Papers by Author: Yan Qin

Abstract: Damping Materials Have Been Wildly Used in Aerospace, Traffic, Construction Fields and so on. The Piezo-Damping Materials Have Received much Attention due to the Novel Energy Loss Mechanism. In this Paper, Piezo-Damping Composite Materials Were Prepared from the Epoxy Resin (EP) as the Resin Matrix, Nano Lead Titanate (Nano-PT) Ceramics as Piezoelectric Material and Chopped Carbon Fibers (CF) as Conductive Materials. The Mechanical and Damping Properties of the Composites Were Analyzed by Mechanics Test, DMA and Vibration Beam Method. The Results Showed that when the Nano-PT Content Was 60% of EP and CF Content Was 0.25% of EP, the Composite Got the Better Mechanical Properties. Form DMA, the Loss Factor (tanδ) Peak Reached 0.58. Damping Temperature Range △T (tanδ>0.3) Was about 36.3°C. In Comparison, Damping Loss Factor Measured by Vibration Beam Method Was 0.82.

Abstract: A novel soybean oil monoglyceride based unsaturated polyester resin (SOMGUPR) was prepared using two step polymerization with soybean oil,glycerol,1.2-propanediol,maleric anhydride and phthalic anhydride. FT-IR spectroscopy ,Gel Permeation Chromatography (GPC) and 1H-NMR spectroscopy were employed to study the chemical structure and molecular weight of this unsaturated polyester resin. The results show that 190°C is the optimal temperature to controll the extent of estification reaction.The number-average molecular weight(Mn) decrease with the increasing value of nglycerol:nsoybean oil in SMOGUPR.Also,the side reaction between SOMG and maleric anhydride has not occured as evidenced by 1H-NMR spectroscopy.

Abstract: In this article, a kind of SMC artificial marble was prepared. In order to enhance the mechanical properties and prolong the using life of SMC artificial marble, some effects such as fiber content, filler content and molding temperature etc. on the mechanical properties were carefully studied, too. Results showed that the increase of fiber content could improve the impact strength of SMC artificial marble when the fiber length was 10mm and the increase of filler content would decrease the flexural strength of SMC artificial marble. And the molding temperature at the range of 130°C ~ 160°C had little influence on the mechanical properties of SMC artificial marble. Comparing with natural marble and casting marble, SMC artificial marble owed superior overall performance and it was much more suitable for industry production.

Abstract: In this paper, a kind of unsaturated polyester resin (UPR) was prepared by using renewable soybean oil, glycerol, propylene glycol and anhydride as raw materials. In this process, soybean oil firstly reacted with glycerol to yield monoglyceride, then, propylene glycol partly replaced by monoglyceride reacted with anhydride to yield UPR. The effect of weight content of monoglyceride on the mechanical properties of UPR was systematically studied. Results showed that with the increase of weight content of monoglyceride, the curing exothermic peak of UPR was dropped; the curing shrinkage and flexural strength and tensile strength were decreased. But the impact strength and the tensile elongation were increased. When the weight content of monoglyceride was 40%, the impact strength and the tensile elongation could reach 102.074 kJ/m² and 27.69%, respectively. The prepared UPR had some advantages such as low-cost, flexible and high production efficiency.

Abstract: This paper introduced a computer simulation model for composite materials which was reinforced by spherical particles. We introduced its algorithm and visualize the model with different particle volume fraction. In order to evaluate the uniformity of the particle distribution, we estimated Particle Center Density and standard deviation of minimal sphere distance.

Abstract: The PMN/EP composites were prepared by resin casting method from PMN powder pretreated with silane coupling agent KH-550. The microstructure of the PMN/EP composite was observed by SEM, the damping property and dielectric property of the composite were investigated by dynamic mechanical analyzer and impedance analyzer respectively. In the composite prepared with PMN powder pretreated by 1.5% silane coupling agent, much epoxy resin fragment is attached in the surface of PMN particles. When the silane coupling agent concentration is 1.5%, the composite shows the best damping property. Dielectric analyses suggest that the dielectric constant of the PMN/EP composite decreases with the increase of silane coupling agent content, however the dielectric loss increases with the increase of silane coupling agent content.

Abstract: Pb(Zr0.53Ti0.47)O3 thin films with thickness of 120nm, 190nm, 310nm, 440nm and 630nm were deposited on Pt/Ti/SiO2/Si substrates by sol-gel process through repeating spining process 2 times, 4 times, 6 times, 8 times and 10 times respectively. The structures of PZT films were investigated by SEM and XRD analysis. The ferroelectric hysteresis loops were recorded by Radiant Precision Workstation and dielectric properties were measured using an Agilent HP4294A impedance analyzer. X-ray diffraction indicated that with the film thickness increasing, the diffraction intensity increased. The thickness of PZT film had great effect on ferroelectric and dielectric properties. Conclusively when the film thickness was about 310nm, the PZT thin films possessed better ferroelectric and dielectric properties.