Creep Of Resin Matrix Composites And Its Effect On Damping Properties

Resin-based composites are widely used in aerospace,transportation and construction industries due to their good physical and chemical properties.But the creep of the resin matrix will change the mechanical properties of the composite material,thus affecting the service life of the composite structure.In this paper,the tensile creep properties of resin-based composites with different laying angles under a certain stress level are studied systematically by applying long-term dead load to resin-based fiber reinforced composite specimens.The expression of the corresponding creep law is established,which provides a reference for the long-term mechanical properties of composite structures.The main contents are as follows:(1)Based on the unique creep properties and viscoelastic properties of composite materials,the theoretical model of the creep compliance and the double logarithmic linear model of the damping loss factor are cited,which laid the foundation for the experimental part and provided theoretical support.(2)According to the initial strength of the composite,the appropriate constant load stress level is determined.The long-term tensile tests of the resin-based composite single-layer specimen with different angles are carried out.The change of creep compliance,material damping loss factor and natural frequency with time is obtained.(3)Based on the experimental data of creep compliance,combined with the bimodal theory model,the creep regularity of different laying angles is fitted and the correctness of the model is verified;The damping experiment data of the material are fitted by double logarithmic linear model;according to the theory of composite material mechanics,the expression of time for the apparent modulus and damping loss factor of the material under arbitrary laying angle is obtained.