Processing and properties of PZT-fibers for 1-3 composites
Sol-gel derived PZT-fibers were prepared by the melt spinning method. The fiber diameter was adjusted in the range of 5 to 50 mu m. As-spun gel fibers were dried. pyrolyzed and sintered in controlled atmospheres applying appropriate temperature/time-schedules. Cracks and pores in the fiber microstructure were eliminated by control of exothermic organic burnout and PbO-partial pressure control during sintering. The microstructure development of the fibers was analyzed by SEM/EDS. Tensile strengths values of pyrolyzed and sintered monofilaments up to 90 MPa were determined. Ferroelectricity was detected in PZT-grains of monofilaments by means of "in situ" polarization in an atomoc force microscope (AFM). Sintered PZT-fiber bundles were uniaxially aligned and infiltrated with epoxy resin. Permittivity and the poiling characteristics of the 1-3 composite were measured.