Experimental studies on the loss factor of alternately laminated anisotropic damped thin plates

Optimization designs on the parameters of seven-layers of alternately laminated thin plate structures have been carried out through two orthogonal experiments and a dynamic mechanical analysis apparatus (DMA Q800), including the variations of damping material species, the fiber orientation angle in constrained layers and the thickness of the damping layer. The effects of these parameters on the loss factor of the structures have been investigated. It may provide some experimental basis for new anisotropic design system of the alternately laminated damped structures. Firstly, the experimental results show that the second and the sixth damping layers are respectively the best-influencing layers on the frequency range and the temperature range of the loss factor. As for the second damping layer, the greater the thickness, the better the frequency characteristics of internal friction. Secondly, the effects of the second outer constrained layer on the loss factor are the highest, and the structural damping characteristics are best when the orientation angle is close to 90. Finally, temperature and frequency characteristics of the loss factor can be optimized with different damped materials in different damping layers.