Flexural fatigue behavior of novel co-curing damping composite structures

Abstract

In order to investigate the flexural fatigue performance of novel carbon fiber reinforced bismaleimide resin matrix damping sandwich composite structure prepared by co-curing process, three-point flexural fatigue tests were carried out on composite structure embedded with damping films of different thickness. The flexural fatigue failure mode, fatigue life and damage evolution law of sandwich beam were obtained, and different damage mechanisms of sandwich beam under flexural fatigue load were analyzed. The S-N curves of undamped composite were fitted by three-point flexural fatigue test. The fatigue characteristics of the undamped composite and damping composite were compared and analyzed. The results showed that the fatigue life of damping composite decreased with the increase of damping layer thickness under the same cyclic load. A numerical simulation model of three-point flexural fatigue performance of damping composite was established. The fatigue life variation trend of damping composite under different damping layer parameters (number of damping layers, location of damping layers, distribution of damping layers) was further simulated, which provided theoretical basis for the fatigue design of damping composite.