Investigation On The Mesoscpic Mechanics Properties Of Aramid Fiber Composites

Aramid fiber composites as a new kind of structural material, caused the wide attention of scholars with its superior properties, especially used as the conveyor belt in the field of material transported by the favour of people. Because of the complexity and designability of the mesoscopic structure of composite materials, combined with aramid fiber yarn crisscrossed beam of woven fabric structure, so it is very difficult to design the structure of composites only by the experimental method. Based on the above reasons, in this paper the mesoscopic mechanics properties of aramid fiber composites were studied by the finite element analysis method. The main work is as follows:1. The finite element simulation analysis of the plain woven composites, which aramid fiber as the skeleton material and EPDM as the matrix, was studied by using ANSYS software. A3D mesoscopic finite element model of plain woven composites was established in the boundary condition of considering the friction contact between warp and weft. In this part, the mesoscopic stress and strain distribution of plain woven composites and the effect of yarn dip angle, the coefficient of friction between warp and weft on the mesoscopic mechanical properties of aramid fiber composites were analyzed. The results showed that, there was a obvious stress concentration phenomenon at the interface between warp and weft, which were in a acceptable agreement with the practical situation. With the increase of yarn dip angle, the yarn buckling degree rose and the stress concentration significantly increased. Both axial effective modulus and strength conservation rate of yarn decreased, and the mechanical properties of materials were reduced.2. The mesoscopic finite element model of plain woven, twill woven and straight warp and straight weft woven were established. In this paper, the equivalent stress distribution of skeleton material, stress-strain relationship, effective modulus and modulus retention performance were analyzed. The results showed that, compared with plain woven and twill woven, the straight warp and straight weft woven was more suitable as the reinforcing fabrics structure for high-strength rubber conveyor belts. The simulation results are in good agreement with the experimental measured results, and the reliability of the finite element model was proved. Some reference for design optimization of aramid fiber composites were provided.