Study On Properties And Applications Of Piezoelectric-damping/Epoxy Composite

Because of the nature of deformation energy, damping materials is widely used in modern aviation, aerospace, marine, transportation, heavy machinery and other areas to control broadband random noise, the vibration and noise excitation. In research and development of damping material fields, the piezo-damping materials have received much attention for the novel energy loss mechanism.The PMN/CB/EP composites of bisphenol-A epoxy resin (EP), Magnesium Niobate-Lead Titanate (PMN) piezoelectric ceramic of high piezoelectric property and conductive materials that include carbon (CB) are prepared by casting and pressing methods. By changing the composition of each component, study the composition of PMN/CB/EP composite damping properties, and use of DMA and DASP testing the damping properties of materials. Determine the optimal damping ratio, and this ratio as a damping layer composite material is prepared loading capacity bearing model hull structures, and get the damping performance of the test related engineering parameters. It can get the following conclusions from the test and analysis:1. In this paper, the CYD-127 epoxy cured by 10% polyethylene polyamine (mass ratio) mixed with 30% polyamide curing system, and the loss factor of the resulting cured product is 0.82. Curing conditions are room temperature curing 4h and 100℃after curing 2h.2.0-3 PMN/EP composite materials are prepared by casting molding and the damping performance testing find that the damping property of PMN/EP composites is better than the CYD-127 epoxy cured product, based on the piezoelectric effect of PMN. The damping property has the nonlinear changing with the PMN content increasing. When the PMN volume fraction reaches 20%, the damping property of PMN/EP composites is the best.3.0-3 PMN/EP composite materials are prepared by casting molding. When the carbon content (mass ratio) was 6%, PMN/CB/EP composite materials get the best damping properties.4. It has built a simulation model of the hull loading capacity bearing. It is prepared a specimen of piezoelectric composite structure which used the PMN/CB/EP composite as a damping layer.5. The first natural modal damping factor of composite structure is 0.4156, difference of vibration level is 4.64-16.79dB, and insertion loss is 6.32dB 18.02dB.It infers that the PMN/CB/EP composite as damping layer can play a good effect, and also damping property of the structure is well. On the contrary, the difference of vibration level of the steel structure is 0.69-1.72dB, because that metallic materials'damping factor is so small that the structural system damping is poor.