Fabrication And Properties Of Piezoelectric Fibers And Cement Based Composite Materials

The cement-based piezoelectric composites have a much higher piezoelectric voltage constant compared with single-phase piezoelectric ceramics, it makes the cement-based piezoelectric composites sensors more compatible with concrete structure. Then the using frequency is expanded, the sensitivity and resolution are improved. In addition, this kind of piezoelectric composites can be used to make piezoelectric generator for acquiring the ambient vibrating energy, the research on the piezoelectric generator is a hot spot in recent years. However, research on the piezoelectric sensors based cement-based piezoelectric composites is rarely reported. And the study on large-scale power generation using piezoelectric materials is almost blank in domestic. In the view of these facts, the properties of the cement-based piezoelectric composites against the background of civil engineering are investigated in this dissertation, the main research contents are summarized as follows:(1) The PZT-51 ceramic fibers were prepared by the method of viscous polymer processing (VPP). The influence of organism in the clay and sintering condition on the properties of PZT fibers were investigated. The results show that the best sintering condition was holding 0.5h at 1290oC, the optimized composites of the clay was 30:3:1 (PZT-51: PVA binder: glycerin, wt%).(2) The green bodies of PZT-51 ceramic fibers were fabricated by extrusion of PZT-51 powder and PZT sol mixture. The amount of acetic acid and water in sol were investigated, and then the method is compared with VPP.(3) 0-3 cement-based piezoelectric composites were fabricated. The effects of the particles size, grain composition and particle shape on the piezoelectric properties, the dielectric properties and electromechanical coupling properties of 0-3 cement-based piezoelectric composites were investigated.(4) 1-3 cement-based piezoelectric composites were fabricated. The effects of the volume content of the PZT-51 piezoelectric fiber on the piezoelectric properties, the dielectric properties and electromechanical coupling properties of 1-3 cement-based piezoelectric composites were investigated.(5) The concept of 0-3-1 cement-based piezoelectric composite was put forward, and the 0-3-1 cement-based piezoelectric composites were prepared. The properties of 0-3-1 cement-based piezoelectric composites were compared with 0-3 cement-based piezoelectric composites.