Papers by Author: Lian Xiang Ma

Abstract: This paper uses the ABAQUS finite element analysis software for modeling and nonlinear analysis of aircraft tires. Paper H44.5 × 16.5-21 aviation tires, The plastic material of the tire subjected to uniaxial stretching to obtain a rubber such as Young's modulus, Poisson's ratio of the material parameters. Uniaxial tensile test tests the tensile properties of the rubber, the use of large-scale numerical calculations and fitting analysis of the experimental data analysis software Matlab, Yeoh model mechanical parameters.

Abstract: In UHF band, the effects of carbon black component on the dielectric properties of rubber composites are studied through experiments. The results show that the content of the carbon black have great effects on the dielectric properties of the composite rubber. The higher content of the carbon black in the rubber composite, the larger the permittivity and dielectric loss tangent. At the same time, the operating frequencies also have great influence on the dielectric properties of the rubber composite. In the UHF band, the permittivity and the dielectric loss tangent of the rubber composites decrease with frequency increasing.

Abstract: The performance of the RFID tag which was implanted into the tire was studied. The shape of implanted RFID antenna, package form and the process of RFID implantation were given. In the same time, experiments were carried out to test the performance of RFID tag which implanted into the tire. The results show that: the read distance is shorten after implanted in the tire, the sidewall of the tire is the idea position for RFID tag implantation, and it can achieve good performance by changing the structure of the RFID antenna and improving implantation process.

Abstract: Eight kinds of carbon black filled natural rubber composites were prepared, and thermal conductivity was studied. Acetylene black contributes much to the thermal conductivity of rubber, and tiny loading results in considerable improvement. The conductive carbon black 40B2 is advantageous for the improvement in thermal conductivity of rubber when its loading reaches middle level, and at its middle level, also tiny loading results in much improvement. Most kinds of carbon black for rubber application filled rubber composites have good properties except for N134 and N660, especially the poor contribution of N660. Additionally, in the case of carbon black filled rubber composites, addition of filler may not necessarily benefit the thermal conductivity when filler loading is not much.

Abstract: In order to improve the thermal conductivities of composites, AlN are used as thermal conductive fillers of EPDM rubber. The contact angle and surface free energy of AlN and modified AlN are studied. The influence filler amount and the surface treatment of AlN which coated by phenol formaldehyde resin (PF), on the thermal conductivities and mechanical properties of composites material are also investigated. The results show that the surface free energy of modified AlN is lower than unmodified, so the modified AlN are easier dispersion in the matrix. Through the TGA analysis, it can give a quantitative analysis of the surface coating thickness. With the increase of the filler, the thermal conductivities of composites are all on the rise, while the mechanical properties decreased in different degree. The modified AlN have active impacts on the thermal conductivities and harmful to mechanical properties of the filled EPDM rubber.

Abstract: In this article, in order to improve the thermal conductivities and mechanical properties of EPDM filled with carbon nanotubes, phenol formaldehyde resin is used to coat to the surface of carbon nanotubes so as to improve the dispersion in rubber matrix and the combination with EPDM. The results show that with the ratio of CNTs and PF increased, the thermal conductivities of carbon nanotubes/EPDM composites show upward trend. Besides, with the increase of filler content, thermal conductivities of composites are improved as well. However, the mechanical properties of composites are declined. Therefore, more effective methods of modification of carbon nanotubes should be attempted, and more experiments should be conducted to improve mechanical properties of filled EPDM and ensure the high thermal conductivities at the same time.

Abstract: Normal thermal conductivity of amorphous and crystalline SiO₂ nano-films is calculated by nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 100 to 700K and thicknesses from 2 to 6nm. The calculated temperature and thickness dependences of thermal conductivity are in good agreement with previous literatures. In the same thickness, higher thermal conductivity is obtained for crystalline SiO₂ nano-films. And more importantly, for amorphous SiO₂ nano-films, thickness can be any direction of x, y, z-axis without effect on the normal thermal conductivity, for crystalline SiO₂ nano-films, the different thickness directions obtain different thermal conductivity results. The different results of amorphous and crystalline SiO₂ nano-films simply show that film thickness and grain morphology will cause different effects on thermal conductivity.

Abstract: Carbon black has been used as the main reinforcing fillers that increase the usefulness of rubbers. In this experiment, different compounds based on natural rubber were prepared with carbon black (N330) at various loading ratios from 10 to 125 phr. The mechanical and thermal properties of rubber compounds were measured and the test data with SEM micrographs were analyzed to determine the suitable ratio of carbon black for the desired properties of rubber compound. The results showed that carbon black particles were well dispersed in compounds with loading ratios of 25-30 phr, corresponding to maximum tensile strength values. While with the increase of carbon black content, heat conductivity kept sustained increase. Fractal dimension characterized the degree of uneven dispersion of carbon black in rubber fracture surfaces. A particular value of fractal dimension was obtained to characterize the optimum mechanical property of carbon black filled natural rubber. The thermal property and fractal dimension demonstrated same variation tendency.

Abstract: Rolling resistance can impact on the fuel economy and dynamics of automobile. Numerical simulation can predict the rolling resistance and reduce the experimental cost. So, a simulation model was established base on ANSYS to compute the rolling resistance. Firstly, the 3D model finite element model of a radial tire was setup to solve the strain and stress of a rolling tire. Secondly ,the temperature field of tire was analyzed in line with the analytical result of the strain and stress. Thirdly, the rolling energy loss was calculated to solve the rolling resistance. The simulation method is conducive to the structural design of tire and computation or prediction of the rolling resistance of tire.

Abstract: The heat conductive silicone rubber is prepared with methy1 viny1 silicone rubber as basic gum and SiCp (SiC particle), SiCp/SiCw (SiC whisker), graphite as heat conductive fillers. The effects of filler amount, filler shape, filler size and coupling agent on the thermal conductivity of silicone rubber have been studied in this article. The result shows that when the filling amount is increasing, the thermal conductivity of composite silicone rubber will increase too. There is no evident change for thermal conductivity with the small filling fraction, while the filling amount reaches a certain value, the thermal conductivity of composite increases obviously. Moreover, the thermal conductivity added with coupling agent (KH-602) is higher than that of composite without coupling agent addition.