The Improvement Of Preparation And Performance Analysis Of The Piezoelectric Composite With Spiral Structure

Piezoelectric composite materials are widely used in sensors,transducers and other fields,because of its piezoelectric properties,flexibility and low dielectric constant.In this paper,a new method for preparation of 1-3 piezoelectric composites with a spiral structure is presented.0.25PZN-0.75PLZT ceramic/epoxy resin composite based on a spiral ceramic skeleton was fabricated by a roll forming-curling method,and a series of composite materials with different volume fractions were prepared.The piezoelectric constant,dielectric constant and electromechanical coupling coefficient of the piezoelectric composites were measured and analyzed.In this paper,1220?is the best sintering temperature for preparing Piezoelectric ceramic.The ceramic phase density is 7.76 g/cm³ under the condition of1220?.After recombination,piezoelectric composites get the optimal performance.With the increase of volume percent of ceramic phase volume,piezoelectric coefficient d₃₃ values and dielectric constant increase gradually.K_t value decreases continuously with the increase of ceramic phase volume fraction.When ceramic phase volume fraction is less than 60%,K_t decreased slowly;when it is more than60%,K_t drops rapidly.With the increase of content of ceramic phase,hydrostatic strain coefficient dh increase first and then decrease,hydrostatic pressure voltage coefficient g_h decreases,optimal value HFOM increases first and then decrease.With 70%-80%ceramic phase volume fraction,piezoelectric composite material has the best acoustic performance,d_h=343 PC/N,g_h=342.5×10^-3 V/MPa,HFOM=4449^-1 pa.With the increase of the polarization electric field intensity,of the longitudinal piezoelectric constant d₃₃,relative dielectric constant,the hydrostatic strain coefficient d_h of Piezoelectric composite materials possess similar variation law,all are gradually raised.When 2 kV/mm and 3 kV/mm polarization field strength were respectively applied,dielectric,piezoelectric and acoustic performances are relatively close.So the optimal polarization field strength is 2 kV/mm,under this condition d₃₃=PC/390 N,?_r=1912,D_h=343 PC/N.Using finite element software ANSYS simulated the stress and strain distribution under the effect of electric field and the total deformation of spiral piezoelectric composite material Analyzed and concluded that various parameters of piezoelectric composite ceramic materials,such as d₃₃,?_r,K_p,all have the same change rules with the change of ceramic phase volume fraction.In the ceramic phase volume accounted for more than 60%,K_t decline rapidly,this point can be used as a cut-off point.This is consistent with the experimental results.